cssi/SciSciGPT-SciSciNet huggingface dataset:
Void growth in 6061-aluminum alloy under triaxial stress state

Abstract In numerous metals and alloys, ductile fracture involves void nucleation, growth, and coalescence. In this contribution, void growth has been quantitatively characterized in an extruded 6061-wrought Al-alloy as a function of stress state in notch tensile test specimens. Digital image analysis and Stereology have been used to estimate the volume fraction and three-dimensional number density of voids in a series of interrupted notch tensile test specimens where the local stress state is predominantly triaxial. Finite elements (FE) simulations have been used to compute the stress states at different locations in the specimens. The computed stress states and experimentally estimated average void volume are utilized to verify analytical void growth models. Lack of agreement between the predictions of the models and the experimental data is due to interactions between neighboring voids, which are ignored in the theoretical models, and continuous void nucleation. The following empirical damage evolution equation is obtained from the experimental data on void volume fraction expressed as % ( f ), and the corresponding local equivalent plastic strain ( e p ) and stress triaxiality ( I ) computed from FE simulations: f = a + b ln[ e p ]+ cI . In this equation, a , b and c are empirical constants whose values depend on the alloy chemistry, heat treatment, and microstructure. The equation is useful only for 6061(T6) Al-alloy.
A note on the threshold electric fields for microwave spark chambers

Abstract The authors are reporting on a theoretical formulation supported by an experimental program, giving the electric field threshold necessary to produce minimum perceptible tracks in microwave spark chambers containing neon-argon mixtures. This formulation gives an electric field threshold which is within 10% of the authors experimental results.
Subthreshold excitatory activity and motoneuron discharge during REM periods of active sleep

A striking paradox of the rapid eye movement periods of active sleep, which are typically characterized by the exacerbation of somatomotor atonia, is the occurrence of muscle twitches and jerks. The purpose of this study was to examine the specific motoneuron membrane potential processes responsible for these myoclonic patterns of activity. In lumbar motoneurons, examined intracellularly in the cat prepared for long-term study, these processes consisted of recurrent depolarizing membrane potential shifts and spontaneous action potentials that were either full-sized or of partial amplitude. In addition, the invasion of antidromically induced spikes into the soma was often blocked. Hyperpolarizing potentials were evident in the intervals between spontaneous spikes. Hyperpolarization was also observed immediately before depolarization and spike activity, in contrast to the gradual depolarization of the motoneuron membrane potential that always occurred during wakefulness. Thus, during rapid eye movement periods, in conjunction with muscle twitches and jerks, a strong excitatory input is superimposed on a background of inhibitory input. The unique patterns of membrane potential change that arise thus seem to result from the simultaneous coactivation of excitatory and inhibitory processes.
Designing Interdisciplinary Science/Humanities Courses: Challenges and Solutions

Interdisciplinary teaching requires substantial effort to integrate the disciplines, especially when a wide interdisciplinary gap exists, such as when a course bridges the sciences and humanities. Creating successful science/humanities courses requires more than good intentions; it demands awareness of the challenges that faculty encounter in such courses, along with specific strategies to meet these challenges. We compile findings from theories, case studies, and instructional guides in the interdisciplinary literature, along with faculty interviews and our own teaching experience, to present seven main challenges and suggested strategies for each.
Measurable Dynamics of Simple p-adic Polynomials

(2005). Measurable Dynamics of Simple p-adic Polynomials. The American Mathematical Monthly: Vol. 112, No. 3, pp. 212-232.
Late Pleistocene Vegetation and Degree of Pluvial Climatic Change in the Chihuahuan Desert

Eight Pleistocene wood rat middens at elevations of 1200, 880, and 600 meters in the Chihuahuan Desert contain abundant macrofossils of pinyon pine, juniper, shrubby liveoak, and Opuntia, together with smaller quantities of Agave lecheguilla and other xerophytes of existing desert vegetation, which in dicate a xerophilous woodland vegetation in the lowlands, as much as 800 meters below existing woodland, during the Wisconsin pluvial. Ten radiocarbon dates show ages that range from 11,560 to 14,800 and 16,250 to 20,000 years, and to more than 40,000 years. Absence of most mesophytic montane species in deposits as high as 1200 meters indicates a lack of equivalent downward dis placement for the ponderosa pine zone or other zones of montane vegetation. Uneven stocking of isolated peaks in the Chihuahuan Desert province with montane species suggests that long-distance transport of propagules, rather than former continuity, may account for the disjunct distributions of many species.
Leisure-time physical activity patterns by weight control status: 1999-2002 NHANES

Introduction: Regular physical activity reduces the risk of hypertension, type 2 diabetes, coronary heart disease, stroke, and some cancers. Physical activity is associated inversely with overweight and obesity prevalence, thus potentially assisting in weight control efforts. Purpose: The purpose of this paper is to examine the variability of physical activity levels and their patterns by self-reported weight control status in a nationally representative sample. Methods: Four years of data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) were used to examine leisure-time physical activity patterns (regular, irregular, inactive) and the prevalence of weight control practices (trying to lose, trying to maintain, not trying to lose or maintain) among U.S. adults (N = 9496). Results: The prevalence of regular physical activity was 32.6% among people trying to lose weight, 37.9% among people trying to maintain weight, and 21.8% among those not trying to lose or maintain weight. Those trying to lose weight were almost three times as likely to be regularly active (vs inactive), and those trying to maintain weight were over three times more likely to be regularly active (vs inactive) than those not trying to lose or maintain weight. The most commonly reported activities among those trying to lose weight were walking (38.3%), yard work (14.5%), biking (12.5%), and running (11.6%). Conclusions: Despite the importance of physical activity, fewer than half the people trying to lose or maintain weight were regularly active during leisure-time. People trying to lose or maintain weight had a higher likelihood of being regularly active than those not trying to lose or maintain weight. Walking was the most common type of physical activity among all weight control groups. Health promotion efforts should promote increased levels of physical activity among all adults.
Comparison of near-forward light scattering on oceanic turbulence and particles

We examine and compare near-forward light scattering that is caused by turbulence and typical particulate assemblages in the ocean. The near-forward scattering by particles was calculated using Mie theory for homogeneous spheres and particle size distributions representative of natural assemblages in the ocean. Direct numerical simulations of a passive scalar with Prandtl number 7 mixed by homogeneous turbulence were used to represent temperature fluctuations and resulting inhomogeneities in the refractive index of water. Light scattering on the simulated turbulent flow was calculated using the geometrical-optics approximation. We found that the smallest temperature scales contribute the most to scattering, and that scattering on turbulence typically dominates over scattering on particles for small angles as large as 0.1°. The scattering angle deviation that is due to turbulence for a light beam propagating over a 0.25-m path length in the oceanic water can be as large as 0.1°. In addition, we carried out a preliminary laboratory experiment that illustrates the differences in the near-forward scattering on refractive-index inhomogeneities and particles. © 1998 Optical Society of America OCIS codes: 010.7060, 290.4020, 080.2710.
Three-dimensional printing of metal parts for tooling and other applications

Three-Dimensional Printing is a Solid-Freeform Fabrication process that creates parts out of powder by spreading layers into which binder is ink-jet printed to define the part geometry of that layer. By repetition of the process layer-by-layer, three-dimensional components of very complex geometry can be created. This paper describes key aspects of the application of Three-Dimensional Printing to the fabrication of metal tooling where surface finish, dimensional accuracy, wear resistance, and process complexity impose challenging constraints on materials selection and processing.
The rotator&#8212;A new network component

This paper presents a new linear, reciprocal, active two-port network element called a rotator, of which there are three types: an R- rotator, an L-rotator, and a C-rotator. They have the unique property that whenever a nonlinear resistor, inductor, or capacitor is connected to one port of an R-, L-, or C-rotator, respectively, the resulting two-terminal network behaves as a new resistor, inductor, or capacitor whose characteristic curve is that of the original resistor, inductor, or capacitor, rotated by a prescribed angle about the origin. The rotator is realizable by either a π-network or a T-network of linear resistances, inductances, or capacitances. It can also be realized by a balanced lattice network of linear elements. Operational laboratory models are reported, and experimental data agree remarkably well with theoretical predictions. The sensitivity, power rating, and stability performances of rotators are considered in detail in this paper, and practical stability criteria are given. They are shown to be indispensable building blocks for realizing multivalued elements, and some potential applications are described.
Distinct hypomyelinated phenotypes in MBP-SV40 large T transgenic mice

To study the effect of SV40 large T-antigen expression in myelin-forming cells of both the central and peripheral nervous system, a series of transgenic mice were generated expressing the SV40 large T-antigen under control of the myelin basic protein (MBP) promoter. Two neurologic phenotypes, designated A and B, appeared among individual transgenic founders and their progeny. The A mice developed a severe action tremor at about 10 days of age that progressed into periods of convulsions and early death by three to four weeks of age. In contrast, the B mice exhibited a progressive hindlimb ataxia and had a more normal lifespan. The A mice displayed hypomyelinating lesions in the central nervous system (CNS), whereas the B mice had lesions in either the peripheral nervous system (PNS) alone or in both the PNS and CNS. Immunohistochemical staining of spinal cord sections of a type A mouse showed a substantial depletion in MBP. Moreover, T-antigen-positive cells appeared predominantly in white matter tracts as randomly distributed single cells. Double labeling immunocytochemistry demonstrated that some of these T-antigen-positive cells were positive for oligodendrocyte differentiation markers MBP and O4. Thus, T-antigen expression appeared to coincide with a terminal stage of oligodendrocyte differentiation.
Performance optimization of photorefractive excisors

In many sensor protection applications, it is useful to selectively attenuate a strong coherent beam in the presence of a collinear, weak white­ light image. We call a device which can perform this function a "coherent beam excisor." One convenient approach for sensing coherence is to divide the input beam and recombine it in a pho­ torefractive material (see Figure la). The portion of the input beam which is coherent will write a refractive index grating, resulting in energy exchange between the two beams. Inparticular, the sample can be oriented so that a large fraction of the energy in the coherent beam is diverted away from the direction of the incoherent white light. Put differently, we wish to optimize the depletion of the signal beam, accompanied by strong amplification of the probe beam. Several recent studiesl.2 have shown that photorefractive two-wave mixing is a viable means of implementing a coherent beam excisor. The only disadvantage of this approach is that portions of the optical train are not coaxial; a beamsplitter and at least one turning mirror are required to form the auxiliary probe beam. One obvious simplification is to use a single beam (Figure 1b), with the role of the second beam now taken by scattered light inside the crystal. This beam fanning approach was actually the first photorefractive limiter reported in the literature.3 Recently, Salamo, et al.4 have proposed an intermediate solution consisting of a single inci­ dent beam, with a grating in contact with the entrance face of the crystal (see Figure le). The grating can be blazed so as to produce a single diffracted order, with a controlled diffraction efficiency. The diffracted beam can be looked upon as the probe beam in a two-wave mixing approach, or an auxiliary seed beam in the fan­ ning approach. Inany case, the diffracted beam will be amplified, leading to depletion of the signal beam. Until recently,5 no systematic study of excisor performance using a grating for probe generation has been undertaken. In particular, the effect of walkoff of the probe beam has not been considered. The ideal beam crossing posi­ tion is at the center of the sample, but the use of a separate grating places the effective beam cross­ ing position at the entrance face of the crystal. In this paper, we have simulated the operation of a grating by using a separately generated probe beam with a variable intensity, which can be set to cross the signal beam at a number of positions. We measured both the rejection and the activation energy. We will show that a factor of -10 improvement in activation energy can be obtained (compared to a pure fanning geometry), even when the beams cross at the entrance face.
DEOXY-ATP (dATP) LEVELS IN ADENOSINI DEAMINASE (ADA) INHIBITED HUMAN PERIPHERAI BLOOD B AND T LYMPHOCYTES CULTURED IN DEOXYADENOSINE (AdR): 74

DEOXY-ATP (dATP) LEVELS IN ADENOSINI DEAMINASE (ADA) INHIBITED HUMAN PERIPHERAI BLOOD B AND T LYMPHOCYTES CULTURED IN DEOXYADENOSINE (AdR): 74
Status epilepticus produces chronic alterations in cardiac sympathovagal balance.

Summary Purpose: Status epilepticus (SE) activates the autonomic nervous system, increasing sympathetic nervous system control of cardiac function during seizure activity. However, lasting effects of SE on autonomic regulation of the heart, which may contribute to mortality following seizure activity, are unknown. Therefore, autonomic control of cardiac function was assessed following SE. Methods: Using Sprague-Dawley rats after 1–2 weeks of recovery from lithium-pilocarpine-induced SE or control procedures, we tested overall sympathovagal control of the heart, the individual contributions of the sympathetic and parasympathetic components of the autonomic nervous system, and baroreflex sensitivity. Results: SE induced a chronic shift in sympathovagal balance toward sympathetic dominance resulting from decreased parasympathetic activity. Baroreflex sensitivity to increased blood pressure was also decreased, likely resulting from diminished vagal activation. Discussion: Chronic alterations in autonomic regulation of cardiac function, characterized by increased sympathetic dominance, occur following SE and likely contribute to subsequent increased cardiac risk and mortality.
The Abused Inhalant Toluene Differentially Modulates Excitatory and Inhibitory Synaptic Transmission in Deep-Layer Neurons of the Medial Prefrontal Cortex

Volatile organic solvents such as toluene are voluntarily inhaled for their intoxicating effects. Solvent use is especially prevalent among adolescents, and is associated with deficits in a wide range of cognitive tasks including attention, behavioral control, and risk assessment. Despite these findings, little is known about the effects of toluene on brain areas mediating these behaviors. In this study, whole-cell patch-clamp recordings were used to determine the effect toluene on neurons within the medial PFC, a region critically involved in cognitive function. Toluene had no effect on measures of intrinsic excitability, but enhanced stimulus-evoked γ-amino butyric acid A-mediated inhibitory postsynaptic currents (IPSCs). In the presence of tetrodotoxin (TTX) to block action potentials, toluene increased the frequency and amplitude of miniature IPSCs. In contrast, toluene induced a delayed but persistent decrease in evoked or spontaneous AMPA-mediated excitatory postsynaptic currents (EPSCs). This effect was prevented by an intracellular calcium chelator or by the ryanodine receptor and SERCA inhibitors, dantrolene or thapsigargin, respectively, suggesting that toluene may mobilize intracellular calcium pools. The toluene-induced reduction in AMPA EPSCs was also prevented by a cannabinoid receptor (CB1R) antagonist, and was occluded by the CB1 agonist WIN 55,212-2 that itself induced a profound decrease in AMPA-mediated EPSCs. Toluene had no effect on the frequency or amplitude of miniature EPSCs recorded in the presence of TTX. Finally, toluene dose-dependently inhibited N-methyl-D-aspartate (NMDA)-mediated EPSCs and the magnitude and reversibility of this effect was CB1R sensitive indicating both direct and indirect actions of toluene on NMDA-mediated responses. Together, these results suggest that the effect of toluene on cognitive behaviors may result from its action on inhibitory and excitatory synaptic transmission of PFC neurons.
Three-dimensional visualization and control of electronic warfare (EW) payloads

The proliferation of unmanned vehicles carrying tactical payloads in the battle-space has accelerated the need for user-friendly visualization with graphical interfaces to provide remote command and control. Often these platforms and payloads receive their control functions from command centers located half a world away via satellite communications. Operators require situational awareness tools capable of graphically presenting the remote battlefield asset positions and collected sensor data. Often these systems use 2D software mapping tools in conjunction with video for real time situational awareness. The Special Projects Group (SPG) in the Tactical Electronic Warfare Division of the U.S. Naval Research Laboratory has been developing an operator control interface called the Jammer Control Station (JCS) to provide 3D battle-space visualization with built-in, remote EW payload command and control (C 2 ) capabilities. The JCS interface presents the operator with graphic depictions of both the platforms' states and the RF environment. Text based messaging between the JCS and the EW payload reduces the impact of the system on the available bandwidth. This paper will discuss the use of the SIMDIS 3-D visualization tool as a real-time command and control interface for electronic warfare (EW) payloads.
Organization of a gene cluster expressed specifically in the asexual spores of A. nidulans

We have investigated the organization and regulation of a 13.3 kb region of the Aspergillus nidulans genome that is preferentially expressed during conidiophore development. This cloned DNA segment codes for six polysomal poly(A)RNAs present in dormant asexual spores (conidia) at from 8 to 50 copies per cell. The genes encoding these RNAs occur once per haploid genome, are separate and distinct, appear to be colinear with their mature RNA products and are present in both polarities. Two of the genes have short regions of homology near their 5' ends, but otherwise the segment is internally unique. All of the RNAs are absent from or present at very low levels in wild-type somatic cells (Hyphae) and developing cultures of asporogenous mutant strains. In synchronously conidiating wild-type cultures, each of the RNAs can first be detected at a time coinciding with the appearance of mature spores. Thus this region comprises a cluster of tightly linked, discrete genes, which are all expressed at the same time, but not to the same extent, in a single differentiating cell type.
Fluorescent properties and resonance energy transfer of 3,4-bis(2,4-difluorophenyl)-maleimide.

A fluorescent compound 3,4-bis(2,4-difluorophenyl)-maleimide 1 from the 3,4-diaryl-substituted maleimides was synthesized and determined to have a Stokes shift of 140 nm (λabs 341 nm, λem 481 nm), a high fluorescent quantum yield (Φfl 0.61) and an extinction coefficient e(340) of 48 400 M−1 cm−1 in dichloromethane. For the first time we demonstrated the successful implementation of a 3,4-diaryl-substituted maleimide molecule as a donor component in FRET experiments.
Cognitive processing of one‐ and two‐sided persuasive messages

Studies regarding message sidedness and persuasion indicate that sidedness effects are moderated by the type of two‐sided message employed, but do not indicate why various messages differ in persuasiveness. This research tests two causal models of cognitive processing. Model 1 posits that messages produce general evaluations that prompt the generation of cognitions. Model 2 suggests messages prompt cognitions upon which subsequent evaluations are based. The data are consistent with Model 2 and inconsistent with Model 1 and begin to demonstrate how one‐sided, nonrefutational two‐sided, and refutational two‐sided messages are processed.
On improving the efficiency of truthful routing in MANETs with selfish nodes

In Mobile Ad Hoc Networks (MANETs), nodes depend upon each other for routing and forwarding packets. However, nodes belonging to independent authorities in MANETs may behave selfishly and may not forward packets to save battery and other resources. To stimulate cooperation, nodes are rewarded for their forwarding service. Since nodes spend different cost to forward packets, it is desirable to reimburse nodes according to their cost so that nodes get incentive while the least total payment is charged to the sender. However, to maximize their utility, nodes may tell lie about their cost. This poses the requirement of truthful protocols, which maximizes the utility of nodes only when they declare their true cost. Anderegg and Eidenbenz recently proposed a truthful routing protocol, named ad hoc-VCG. This protocol incurs the route discovery overhead of O(n3), where n is the number of nodes in the network. This routing overhead is likely to become prohibitively large as the network size grows. Moreover, it leads to low network performance due to congestion and interference. We present a low-overhead truthful routing protocol for route discovery in MANETs with selfish nodes by applying mechanism design. The protocol, named LOTTO (Low Overhead Truthful rouTing prOtocol), finds a least cost path for data forwarding with a lower routing overhead of O(n2). We conduct an extensive simulation study to evaluate the performance of our protocol and compare it with ad hoc-VCG. Simulation results show that our protocol provides a much higher packet delivery ratio, generates much lower overhead and has much lower end-to-end delay.
VIBRONIC TRANSITIONS IN NI2

Abstract Nickel dimer ions produced and cooled in a supersonic expansion are studied by two-color resonant photodissociation. Five excited electronic states have been analyzed and their corresponding vibrational frequencies, anharmonicities and electronic origins are presented. The vibrational quantum numbering for all the assigned transitions has been determined via analysis of the spectra of the naturally occurring isotopic variants of the molecule. The ground state stretching frequency for the 58 Ni 2 + is estimated from this isotopic analysis as 270 ± 25 cm −1 .
Impact of Artificial Plaque Composition on Drug Transport

Drug-eluting stent (DES) implantation is a common treatment for atherosclerosis. The safety and efficacy of these devices will depend on the uptake and distribution of drug into the vessel wall. It is established that the composition of atherosclerotic vessels can vary dramatically with patients’ age and gender. However, studies focused on elucidating and quantifying the impact of these variations on important drug transport properties, such as diffusion (D) and partition (k) coefficients, are limited. We have developed an improved tissue mimic or artificial plaque to probe the effect ofvarying concentrations ofplaque constituents on drug transport in vitro. Based on these artificial plaques, we have quantified the impact of gelatin (hydrolyzed collagen) and lipid (cholesterol) concentration on D and k using two model drugs, tetracycline and fluvastatin. We found that for tetracycline, increasing the collagen concentration from 0.025 to 0.100 (w/w) resulted in a fivefold decrease in diffusivity, whereas there was no discernible impact on solubility. Increasing the lipid concentration up to 0.034 (w/w) resulted in only minor changes to transport properties of tetracycline. However, fluvastatin exhibited nearly a fivefold increase in k and 10-fold decrease in D with increased lipid concentration. These results were in reasonable agreement with existing models and exhibited behavior consistent with previous observations on drugs commonly used in DES applications. These observations suggest that variations in the chemical characteristics of atherosclerotic plaque can significantly alter the release rate and distribution of drug following DES implantation.
Chemical modification of cell death in the Bar eye of Drosophila

Cell death during the development of the mutant Bar of Drosophila melanogaster has been further investigated. The temporal and spatial distribution of degenerating cells was determined by light microscopy of serial sections of Bar eye discs. It appears that the presumptive eye cells die during the initial stage of differentiation; i.e., during their organization into groups of cells corresponding to the future ommatidia.
Word completion: a first step toward target-text mediated IMT

We argue that the conventional approach to Interactive Machine Translation is not the best way to provide assistance to skilled translators, and propose an alternative whose central feature is the use of the target text as a medium of interaction. We describe an automatic word-completion system intended to serve as a vehicle for exploring the feasibility of this new approach, and give results in terms of keystrokes saved in a test corpus.
Regional manifestations and control of the immune system

Although immune responses are generally considered to be systemic, local events such as interaction of complement products with blood vessels and with inflammatory cells play a pivotal role in determining the nature and manifestations of immune responses. This paper will discuss how blood vessel physiology and immunity influence one another to reach homeostasis upon exposure to an infectious agent. We review new insights into the mechanisms by which the microenvironment of tissues protects against microbial invasion yet facilitates migration of leukocytes and 'decides' whether immunity or tolerance ensues and whether, in the face of immunity, protective responses or tissue injury ensues. These 'decisions' are made based on interaction of components of normal tissues such as proteoglycans and injured tissues such as cell-associated cytokines with receptors on immune cells and blood vessels.
Accuracy of sonographic diagnosis of superficial masses.

Objectives The purpose of this study was to retrospectively review the diagnostic accuracy of sonography in the evaluation of superficial masses with surgical and histologic findings as the reference standard. Methods Institutional Review Board approval was obtained, informed consent was waived, and Health Insurance Portability and Accountability Act compliance was maintained. Seventy-two superficial masses in 62 patients were examined sonographically by a single radiologist (reader 1) and subsequently underwent surgical therapy. Three radiologists experienced in sonography, blinded to the original interpretation and surgical findings, retrospectively and independently reviewed the sonographic images and assigned the cases to 1 of 14 diagnostic categories. For all lesions, the rendered diagnosis was compared with the reference standard to determine concordance. For the specific diagnosis of lipoma, sensitivity, specificity, and accuracy were assessed for all readers individually and collectively. Results Surgery and histolopathologic analysis yielded 39 lipomas, 6 hernias, 4 foreign bodies, 4 hemangiomas, and 19 other nonlipomatous lesions, including 1 malignancy. The rendered diagnosis was concordant with the reference standard in 93% of cases for reader 1 and in 89% of cases for all readers. The sensitivity, specificity, and accuracy for the diagnosis of lipoma were 92%, 100%, and 96% for reader 1 and 96%, 97%, and 96% for all readers. Conclusions Sonography has high accuracy in the evaluation of superficial masses, particularly lipomas.
A Universal Power Circle Diagram

The usefulness and utility of the conventional power circle diagram can be expanded by translating the origin from the zero of power to the center of the circle. This operation makes all the circles concentric so that they can be printed beforehand on standard sheets of paper. Data for a particular problem then are plotted on the sheet as required. Because of the number of circles that are available immediately, the diagram also can be used for solving problems in which either the receiving- or sending-end voltage is a variable. Such solutions are aided by the plotting of auxiliary loci, which are either straight lines or circles, for constant loss, constant power, constant power factor, and so forth.
Rate-based headend-controlled bandwidth allocation in unidirectional bus metropolitan area networks

The authors introduce and analyze a protocol for unidirectional bus networks in which bandwidth allocation and access fairness are adaptively controlled by the head end of the bus on the basis of traffic measurements. The proposed protocol can control the admitted traffic of a particular type to a desired fraction of the bus capacity and at the same time enforce access fairness faster than other existing protocols, such as the one used in the recently approved IEEE 802.6 metropolitan area network (MAN) standard. >
Cone-bounded nonlinearities and mean-square bounds--Estimation lower bound

This paper is the first in a series of three, the remaining two of which will appear at a later date. Performance bounds are derived in this series of papers for causal state estimation and regulation problems employing mean-square criteria. The systems considered are partially observed finite-dimensional continuous-time stochastic processes driven by additive white Gaussian noise. The particular systems to which the bounds apply are those which, when modeled by Ito differential equations, contain drift (.dt) coefficients which are, to within a uniformly Lipschitz residual, jointly linear in the system state and externally applied control. The bounds derived in the complete series of papers include both upper and lower bounds for causal state estimation and for a quadratic regulator problem. The upper bounds pertain to the performance of some simple, almost linear designs reminiscent of the designs which are optimal in the linear case. The lower bounds pertain to the optimum performance attainable within a broad class of candidate designs. This paper treats the upper bound for estimation. The second paper presents the estimation lower bound. The estimation performance bounds are independent of the control law, giving a particularly simple form to the control performance bounds which are developed in the third, and final, paper. All the bounds converge with vanishing nonlinearity (vanishing Lipschitz constants) to the known optimum performance for the limiting linear system. Consequently, the bounds are asymptotically tight and the simple designs studied are asymptotically optimal with vanishing nonlinearity.
Purification, Thermal Stability, and Antigenicity of the Immunodominant Soybean Allergen P34 in Soy Cultivars, Ingredients, and Products

Protein P34 (Gly m Bd 30K) is the immunodominant allergen in soybean (Glycine max L.). The objectives of this study were (1) to study the effect of thermal treatment on P34 antigenicity and secondary structure after isolation and purification of P34 from soybean by chromatographic techniques; (2) to identify the variability of P34 allergen within 138 accessions from a diverse USDA soybean germplasm collection by ELISA; and (3) to quantify P34 immunoreactivity in various commercial soy ingredients and products. Thermal processing decreased P34 antigenicity. Soybean accessions with the highest P34 content were ancestral (12 mg/g defatted flour) followed by modern (10 mg/g defatted flour) and exotic (8 mg/g defatted flour). The cultivar that emerged as the lowest-expressing P34 accession was PI548657 (2.3 mg/g defatted flour). Among commercial soy ingredients, soy flour yielded the highest P34 antigenicity (32 mg/g extracted protein) followed by soy protein isolate (29 mg/g extracted protein) and soy protein concentrate (24 mg/g extracted protein). Among soy consumer products, soymilk presented the highest P34 antigenicity, ranging from 7 to 23 mg/g extracted protein, followed by tempeh (8 mg/g extracted protein), soy infant formula (3.4 mg/g extracted protein), soy powder (2 mg/g extracted protein), and soy cheese products (0.50 mg/g extracted protein). Korean miso, soy sauce, soy chili mix, soy nuts, soy cream cheese, soy meat patty, texturized soy protein, and soy cereal exhibited undetectable P34 antigenicity (detection limit = 0.45 ng). Selecting soybean varieties with low levels of this allergen, or via processing, could potentially make soybean products less antigenic.
Highly scalable genome assembly on campus grids

Bioinformatics researchers need efficient means to process large collections of sequence data. One application of interest, genome assembly, has great potential for parallelization, however most previous attempts at parallelization require uncommon high-end hardware. This paper introduces a scalable modular genome assembler that can achieve significant speedup using large numbers of conventional desktop machines, such as those found in a campus computing grid. The system is based on the Celera open-source assembly toolkit, and replaces two independent sequential modules with scalable replacements: a scalable candidate selector exploits the distributed memory capacity of a campus grid, while the scalable aligner exploits the distributed computing capacity. For large problems, these modules provide robust task and data management while also achieving speedup with high efficiency on several scales of resources. We show results for several datasets ranging from 738 thousand to over 121 million alignments using campus grid resources ranging from a small cluster to more than a thousand nodes spanning three institutions. Our largest run so far achieves a 927x speedup with 71.3 percent efficiency.
The “how” and “whys” of research: life scientists’ views of accountability

Objectives: To investigate life scientists’ views of accountability and the ethical and societal implications of research. Design: Qualitative focus group and one-on-one interviews. Participants: 45 Stanford University life scientists, including graduate students, postdoctoral fellows and faculty. Results: Two main themes were identified in participants’ discussions of accountability: (1) the “how” of science and (2) the “why” of science. The “how” encompassed the internal conduct of research including attributes such as honesty and independence. The “why,” or the motivation for conducting research, was two-tiered: first was the desire to positively impact the research community and science itself, and second was an interest in positively impacting the external community, broadly referred to as society. Participants noted that these motivations were influenced by the current systems of publications, grants and funding, thereby supporting a complex notion of boundary-setting between science and non-science. In addition, while all participants recognised the “how” of science and the two tiers of “why,” scientists expressed the need to prioritise these domains of accountability. This prioritisation was related to a researcher’s position in the academic career trajectory and to the researcher’s subsequent “perceived proximity” to scientific or societal concerns. Our findings therefore suggest the need for institutional change to inculcate early-stage researchers with a broader awareness of the implications of their research. The peer review processes for funding and publication could be effective avenues for encouraging scientists to broaden their views of accountability to society.
Vertebral artery compression due to head rotation in thalamic stroke

Vertebral artery compression from head turning has been described in adults, especially in those who have spondylosis of the spine and osteophytes. There are no reports that demonstrate vertebral artery compression due to head turning in children without vertebral abnormalities. A child is reported with thalamic stroke in whom cerebral arteriography revealed vertebral artery compression on head turning. Blood flow in the vertebral artery, however, could be demonstrated by Doppler ultrasonography with the head in the midline. It is concluded that the vertebral artery is vulnerable to mechanical compression in the neck even in the absence of bony abnormalities.
Worksite Drug Testing

Drug testing in the workplace presents a striking case of a policy instrument that has penetrated fast and far, accompanied by almost no credible scientific warrant of effectiveness. In just a decade, worksite drug testing programs have made their way through the entire military and all other federal employ­ ment, into many of the nation's largest and most prestigious private corpora­ tions, and all the way to the United States Supreme Court. Meanwhile, solid research has focused almost entirely on the efficacy of the testing procedures themselves, to the virtual exclusion of deeper questions of sound social policy. The most fundamental assumptions on competing sides of unresolved debates over the merits and demerits of screening workers' urine for traces of drugs are untested and untestable, knowing what we currently know. In fact, the gap between science and policy is so wide as to occasion real confusion about which goals are really being served by drug testing programs at work.
AVTIS - a dual-mode imaging millimetre wave radar/radiometer for volcanological surveying

We present the design and preliminary results for an advanced mm-wave remote sensing instrument. AVTIS (AH Weather Volcano Topography Imaging Sensor) is a dual-mode passive imager and active radar operating at 94 GHz, designed to yield topographic and thermal maps of volcanic lava domes. The mechanically scanned imager uses a 0.5m Cassegrain antenna mounted on a pan & tilt gimbal. The radiometer is of the total power heterodyne type, and the radar operates in an FMCW mode. When images are collected from multiple viewpoints, it will be possible to construct a thermo-spatial 3D map of the lava dome. The project volcanologists will use this data to enhance the modeling of the growth and collapse mechanisms in lava domes, which may ultimately lead to improved hazard warning.
Comparative evaluation of photon cross-section libraries for materials of interest in PET Monte Carlo simulations

The many applications of Monte Carlo modeling in nuclear medicine imaging make it desirable to increase the accuracy and computational speed of Monte Carlo codes. The accuracy of Monte Carlo simulations strongly depends on the accuracy in the probability functions and, thus, on the cross-section libraries used for photon-transport calculations. A comparison between different photon cross-section libraries and parameterizations implemented in Monte Carlo simulation packages developed for positron emission tomography and the most recent Evaluated Photon Data Library (EPDL97) developed by the Lawrence Livermore National Laboratory, Livermore, CA, was performed for several human tissues and common detector materials for energies from 1 keV to 1 MeV. Different photon cross-section libraries and parameterizations show quite large variations when compared to the EPDL97 coefficients. This latter library is the more up-to-date complete and consistent library available, and was carefully designed in the form of look-up tables providing efficient data storage, access, and management. EPDL97 is already a standard in the nuclear reactor industry. Its use as a standard in the simulation of medical imaging systems will help to eliminate potential differences between the results obtained with different codes. Together with the optimization of the computing time performances of the Monte Carlo software package, Eidolon, photon transport in three-dimensional (3-D) positron emission tomography could be efficiently modeled to develop accurate scatter models and better understand scatter correction techniques.
Intrapleural Fibrinolytics Combined With Image-Guided Chest Tube Drainage for Pleural Infection

OBJECTIVE To present our method of treating pleural infection by using a combination of image-guided chest tube drainage and intrapleural fibrinolytics. PATIENTS AND METHODS We retrospectively reviewed the medical charts and radiographs of 30 consecutive patients with pleural infection who were seen at our institution from December 15, 1995, to July 1, 2006, 27 of whom received intrapleural urokinase or tissue-type plasminogen activator. End points were death, length of stay in the hospital, and percentage of patients who needed surgery. RESULTS Placement of chest tubes required image guidance 45.7% of the time. Three patients (10%; 95% confidence interval, 2.1%-26.5%) died of complications from pleural infection. None of the 30 patients (0%; 95% confidence interval, 0%-9.5%) required surgery for treatment of pleural infection. The median hospital length of stay was 11 days. CONCLUSION In the treatment of pleural infection, intrapleural urokinase or tissue-type plasminogen activator in combination with careful image-guided placement of chest tubes is highly effective in resolving the effusion and curing the infection.
Improving Cu line Rs control using feed-forward information for CMP endpointing

A promising method for controlling sheet resistance (R s ) of Cu interconnect through improved chemical mechanical planarization (CMP) endpoint capability was developed using broadband spectrometry together with feed-forward information from upstream process conditions. With this new method, the wafer-to-wafer (WTW) R s range was reduced more than 50% compared to time-based CMP polish control.
History of diabetes, clinical features of prostate cancer, and prostate cancer recurrence-data from CaPSURE (United States).

Objectives: There is a growing epidemiologic literature suggesting an inverse association between history of diabetes and risk of incident prostate cancer. To our knowledge, the relationship between diabetes and tumor features and risk of recurrence among men with prostate cancer has not been examined previously. We hypothesized that men with diabetes would present with more favorable prostate cancer and experience lower risk of recurrence. Methods: We identified 691 men with diabetes at the time of prostate cancer diagnosis, among 6722 men diagnosed with prostate cancer in 1989 to 2002 within CaPSURETM, a community-based prostate cancer registry study. We compared clinical and socio-demographic variables by diabetes status, using χ2 tests, t-tests, and multinomial logistic regression. We examined recurrence rates for prostate cancer among patients with and without diabetes using Kaplan–Meier log-rank tests and Cox proportional hazard models. Results: In multivariate analyses, history of diabetes was not associated with any diagnostic clinical parameter, and treatment-specific recurrence rates for prostate cancer generally did not differ by diabetes history. Among men with low-prognostic risk or who were younger at prostate cancer diagnosis, being diabetic (versus not) was associated with an elevated risk of recurrence after radiation therapy, in multivariate analyses. Conclusions: Contrary to data suggesting that diabetes may be modestly protective against risk of incident prostate cancer, we did not observe any evidence of an inverse association between history of diabetes and aggressiveness at diagnosis or risk of recurrence, in this population of men with prostate cancer.
Innovative Math For Liberal Arts Majors

An innovative Math for Liberal Arts course was designed to provide liberal arts students with the life skills necessary to survive in the 21st century. The course emphasizes application driven mathematics. This course has been successful in changing students’ perceptions of the usefulness of the course and improving student success rate as well as actively engaging them in the study of mathematics. Topics such as critical thinking, unit analysis, statistical reasoning, and managing money are included. Students spend time analyzing a budget as well as learning about the stock market and the mathematics associated with each. Students who took this course were far more likely than those who took the more traditional survey type of course to rate the course as being important. The course changes are delineated and the students’ responses to those changes are described.
Spatial heterogeneity and dependence of soils and herbaceous plant communities in adjacent seasonal wetland and pasture sites

ABSTRACT Soil processes often exhibit spatial heterogeneity that may influence plant community structure. This study was conducted to determine fine-scale spatial patterns and degrees of variability of soil nutrients and plant communities within different vegetation types in a stream floodplain in southwestern West Virginia. One 5 m × 5 m site was established in each of two vegetation/drainage types: pasture (PA) and seasonal wetland (SW). Sites were located ∼25 m apart on flat bottomland. A 10 m × 1 m transect was also established perpendicular to the visible boundary between PA and SW drainage types, but separate from the PA and SW sites. Each site was divided into 1-m2 plots (n = 25) and the transect was divided into 0.25-m2 plots (n = 40). Mineral soil was taken to a 5 cm depth. Soil organic matter was measured as loss-on-ignition. Extractable NH4+ and NO3− were determined before and after laboratory incubation (28 days at 27°C) to determine net N mineralization and nitrification. Cations were ana...