cssi/SciSciGPT-SciSciNet huggingface dataset:
Direct syrinx drainage in patients with Chiari I malformation.

While FMD is, to date, the primary treatment of symptomatic CM I, the treatment of Chiari malformation type I (CM I) associated syrinx remains controversial. In cases of persistent, progressive, or recurrent syrinx following FMD, direct syrinx drainage (DSD) is described as a safe and efficient option, leading to a good clinical and radiological outcome. However, studies at hand mostly include very heterogeneous patient populations, small cohorts, and are of retrospective nature. We provide an overview of the possible indications and outcome for DSD in CM I–associated syrinx. We discuss the different surgical techniques of DSD and review the available literature comparing different DSD techniques. Finally, we discuss the possible complications that might occur after DSD and how they can be prevented.
Optimum Structural Design Using Linear Programming

It is frequently true that several trial designs using the same basic structural configuration must be considered before arriving at an acceptable design either in terms of cost or weight. A systematic approach is developed for finding optimum (lightest or cheapest) designs for a wide class of elastic structures. Design parameters are treated as variables and optimization is accomplished by transforming the analysis and design cycle into the solution of a series of linear programming problems. Two examples are used as illustrations including a truss and a rigid frame each subjected to two distinct load conditions. Significant savings in weight may result from a small investment of computational effort. The amount of computation in performing a single cycle of linear programming optimization will not be excessive compared to the computations required for analyzing another trial design.
Degradation properties of a biodegradable shape memory elastomer, poly(glycerol dodecanoate), for soft tissue repair

Development of biodegradable shape memory elastomers (SMEs) is driven by the growing need for materials to address soft tissue pathology using a minimally invasive surgical approach. Composition, chain length and crosslinking of biocompatible polymers like PCL and PLA have been investigated to control mechanical properties, shape recovery and degradation rates. Depending on the primary mechanism of degradation, many of these polymers become considerably stiffer or softer resulting in mechanical properties that are inappropriate to support the regeneration of surrounding soft tissues. Additionally, concerns regarding degradation byproducts or residual organic solvents during synthesis accelerated interest in development of materials from bioavailable monomers. We previously developed a biodegradable SME, poly(glycerol dodecanoate) (PGD), using biologically relevant metabolites and controlled synthesis conditions to tune mechanical properties for soft tissue repair. In this study, we investigate the influence of crosslinking density on the mechanical and thermal properties of PGD during in vitro and in vivo degradation. Results suggest polymer degradation in vivo is predominantly driven by surface erosion, with no significant effects of initial crosslinking density on degradation time under the conditions investigated. Importantly, mechanical integrity is maintained during degradation. Additionally, shifts in melt transitions on thermograms indicate a potential shift in shape memory transition temperatures as the polymers degrade. These findings support the use of PGD for soft tissue repair and warrant further investigation towards tuning the molecular and macromolecular properties of the polymer to tailor degradation rates for specific clinical applications.
Place-Based Community Engagement in Higher Education: A Strategy to Transform Universities and Communities

In Place-based community engagement in higher education: A strategy to transform universities and communities, authors Erica K. Yamamura and Kent Koth presented a theoretical and practical approach...
Proteomic Analysis of the Postsynaptic Density

The postsynaptic density (PSD) is a large protein complex lining the postsynaptic membrane with an average mass around 1 million KDa. The structure appears to be an organized array containing neurotransmitter receptors and signal transduction molecules held together by specialized scaffold proteins. PSDs can be isolated by subcellular fractionation, the most widely used protocols consisting of detergent treatment of synaptosomal fractions followed by further density gradient centrifugation steps. Several groups used mass spectrometric approaches to identify proteins in these PSD fractions. An inherent problem in the determination of PSD composition through analysis of isolated fractions has been the presence of contaminants. A method for further purification of PSD fractions by an orthogonal affinity-based strategy and comparison of the parent and purified preparations to trace the enrichment of proteins allows the compilation of a more restricted list of putative PSD components. Ultimately, however, the presence of the identified proteins at the PSD has to be confirmed by immuno-electron microscopy. Proteomic techniques for relative quantification of proteins are applied for the detection of those proteins whose abundance in the PSD change following synaptic activity, as well as in response to various pathological conditions such as ischemia.
Crossing the Cleft: Communication Challenges Between Neuroscience and Artificial Intelligence

Historically, neuroscience principles have heavily influenced artificial intelligence (AI), for example the influence of the perceptron model, essentially a simple model of a biological neuron, on artificial neural networks. More recently, notable recent AI advances, for example the growing popularity of reinforcement learning, often appear more aligned with cognitive neuroscience or psychology, focusing on function at a relatively abstract level. At the same time, neuroscience stands poised to enter a new era of large-scale high-resolution data and appears more focused on underlying neural mechanisms or architectures that can, at times, seem rather removed from functional descriptions. While this might seem to foretell a new generation of AI approaches arising from a deeper exploration of neuroscience specifically for AI, the most direct path for achieving this is unclear. Here we discuss cultural differences between the two fields, including divergent priorities that should be considered when leveraging modern-day neuroscience for AI. For example, the two fields feed two very different applications that at times require potentially conflicting perspectives. We highlight small but significant cultural shifts that we feel would greatly facilitate increased synergy between the two fields.
Taking Data Out of Context to Hyper-Personalize Ads: Crowdworkers' Privacy Perceptions and Decisions to Disclose Private Information

Data brokers and advertisers increasingly collect data in one context and use it in another. When users encounter a misuse of their data, do they subsequently disclose less information? We report on human-subjects experiments with 25 in-person and 280 online participants. First, participants provided personal information amidst distractor questions. A week later, while participants completed another survey, they received either a robotext or online banner ad seemingly unrelated to the study. Half of the participants received an ad containing their name, partner's name, preferred cuisine, and location; others received a generic ad. We measured how many of 43 potentially invasive questions participants subsequently chose to answer. Participants reacted negatively to the personalized ad, yet answered nearly all invasive questions accurately. We unpack our results relative to the privacy paradox, contextual integrity, and power dynamics in crowdworker platforms.
A Multiinstitutional Study on Wasted CT Scans for Over 60,000 Patients

OBJECTIVE. Repeated imaging is an unnecessary source of patient radiation exposure, a detriment to patient satisfaction, and a waste of time and money. Although analysis of rates of repeated and rejected images is mandated in mammography and recommended in radiography, the available data on these rates for CT are limited. MATERIALS AND METHODS. In this retrospective study, an automated repeat-reject rate analysis algorithm was used to quantify repeat rates from 61,102 patient examinations obtained between 2015 and 2018. The algorithm used DICOM metadata to identify repeat acquisitions. We quantified rates for one academic site and one rural site. The method allows scanner-, technologist-, protocol-, and indication-specific rates to be determined. Positive predictive values and sensitivity were estimated for correctly identifying and classifying repeat acquisitions. Repeat rates were compared between sites to identify areas for targeted technologist training. RESULTS. Of 61,102 examinations, 4676 instances of repeat scanning contributed excess radiation dose to patients. Estimated helical overlap repeat rates were 1.4% (95% CI, 1.2-1.6%) for the rural site and 1.1% (95% CI, 1.0-1.2%) for the academic site. Significant differences in rates of repeat imaging required because of bolus tracking (11.6% vs 4.3%; p < 0.001) and helical extension (3.3% vs 1.8%; p < 0.001) were observed between sites. Positive predictive values ranged from 91% to 99% depending on the reason for repeat imaging and site location. Sensitivity of the algorithm was 92% (95% CI, 87-96%). Rates tended to be highest for emergent imaging procedures and exceeded 9% for certain protocols. CONCLUSION. Our multiinstitutional automated quantification of repeat rates for CT provided a useful metric for unnecessary radiation exposure and identification of technologists in need of training.
Choice of Law in De Facto Parent Cases: Tweaking the 2017 Uniform Parentage Act

The 2017 Uniform Parentage Act (UPA) on “parentage” adjudication follows the 2000 UPA on “parent-child relationship” adjudications by not expressly recognizing that a court applying its own law may sometimes need to utilize its rules on choice of law. Express recognition is necessary, as was done in 1996 Uniform Interstate Foreign Support Act. This need arises due to comity, if not the federal constitutional Full Faith and Credit requirement, in parentage/parent-child settings wherein imprecise norms, especially the newly-recognized de facto parenthood, may be employed. Notwithstanding the Johnson case from North Dakota, one pursued for child support as a parent should not necessarily be assessed as a possible de facto parent under North Dakota law just because suit was brought there, especially when the parent (also a grandmother) seeking support, as well as the child in need of support, never lived in North Dakota and when the alleged parent (also a grandfather) only recently moved to North Dakota.
Experience Report: Exploring the Use of CTF-based Co-Curricular Instruction to Increase Student Comfort and Success in Computing

Very little research exists on the incorporation of co-curricular opportunities, specifically capture-the-flag (CTF) activities, and the impact on computer science students. However, some literature on underrepresented groups in the field of computer science indicates that co-curricular experiences, such as CTF activities, have a significant impact on efficacy and sense of belonging. This experience report seeks to identify and share teaching strategies that impact student learning, efficacy, and sense of self/belonging in the field of Computer Science, for all students. In an effort to design learning opportunities to help bridge the gap between the haves and have nots, and maximize learning for all students, this strategy uses CTF-based instruction as a way to generate and support culture-based, computer science experiences. The aim is to identify instructional strategies that build students' computing skills and improve their comfort participating in computing activities thus broadening participation in computing and cybersecurity. As students' comfort is related to their self-efficacy and sense of belonging, we explore the integration of co-curricular opportunities, specifically a capture-the-flag (CTF) approach to computer science instruction, as means of increasing student success, with regard to learning, efficacy, and sense of belonging/identity. This report involves a description of the class activities as well as data from a series of pre- and post- surveys of the student experience, attitudes, and gain in knowledge. Initial analysis indicates that low-stakes, entry-level exposure to computer science concepts has a positive effect on student comfort and skill acquisition in computing domains external to coursework.
Temporary In Situ Hydrogel Dressings for Colon Polypectomies.

Currently, no dressings are utilized after removal of polyps during a colonoscopy rendering these tissue sites susceptible to bleeding, sepsis, and perfusion. We report the design specifications, synthesis, and ex vivo evaluation of in situ polymerized hydrogels as colon wound dressings post polypectomy. The hydrogels exhibited varied properties to include moduli between 100 and 16 000 Pa, dissolution times between 4 h to 7 days or longer, swelling up to 200%, and adhesion to colon tissue from 0.1 to 0.4 N/cm2. The hydrogels displayed minimal cytotoxicity, prevented the migration/spread of bacteria, and exhibited rapid gelation, a requirement for application to the lumen of the colon via an endoscope. This work highlights the structure-property relationship of hydrogels prepared from N-hydroxysuccinimide functionalized PEG cross-linkers and hyperbranched polyethylenimines or 4-arm PEG-NH2 star polymers, and their potential as colon wound dressings.
Observation of heat transfer due to variable thermophysical properties of sub-, near- and super- critical fluids in porous media by magnetic resonance imaging

Abstract Local velocity and temperature profiles are measured non-invasively using nuclear magnetic resonance (NMR) imaging (MRI) in porous media with a sub-, near-, and supercritical fluid. Heat transfer is driven by natural convection via heating from below. The C2F6 fluid fills the pore spaces in a packed bed of encapsulated phase change material (PCM). As the PCMs melt, 1H signal intensity increases with temperature. Physical properties of C2F6, e.g. thermal diffusivity, vary substantially at the critical point, affecting the rate and magnitude of heat transfer. The changes in bead signal, e.g. temperature, are imaged and measured over time at 27 bar (sub-critical), 32, 34 and 36 bar (near-critical), and 66 bar (supercritical). Despite velocity profile similarities, the temperature in the packed bed varies significantly with thermal diffusivity, the magnitude of which decreases and increases with temperature around the critical point. NMR spatially and temporally captures the resulting dynamic heat transfer processes.
Variations in cell-surface ACE2 levels alter direct binding of SARS-CoV-2 Spike protein and viral infectivity: Implications for measuring Spike protein interactions with animal ACE2 orthologs

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of COVID-19, the most severe pandemic in a century. The virus gains access to host cells when the viral Spike protein (S-protein) binds to the host cell-surface receptor angiotensin-converting enzyme 2 (ACE2). Studies have attempted to understand SARS-CoV-2 S-protein interaction with vertebrate orthologs of ACE2 by expressing ACE2 orthologs in mammalian cells and measuring viral infection or S- protein binding. Often these cells only transiently express ACE2 proteins and levels of ACE2 at the cell surface are not quantified. Here, we describe a cell-based assay that uses stably transfected cells expressing ACE2 proteins in a bi-cistronic vector with an easy to quantify reporter protein to normalize ACE2 expression. We found that both binding of the S-protein receptor-binding domain (RBD) and infection with a SARS-CoV-2 pseudovirus is proportional to the amount of human ACE2 expressed at the cell surface, which can be inferred by quantifying the level of reporter protein, Thy1.1. We also compared different ACE2 orthologs which were expressed in stably transfected cells expressing equivalent levels of Thy1.1. When ranked for either viral infectivity or RBD binding, mouse ACE2 had a weak to undetectable affinity for S-protein while human ACE2 was the highest level detected and feline ACE2 had an intermediate phenotype. The generation of stably transfected cells whose ACE2 level can be normalized for cross-ortholog comparisons allows us to create a reusable cellular library useful for measuring emerging SARS-CoV-2 variant’s ability to potentially infect different animals.
Technical Note: An alternative approach to verify 6FFF beam dosimetry for Ethos and MR Linac without using a 3D water tank

Purpose The current approach to Linac beam dosimetry verification is typically performed utilizing a three-dimensional (3D) water tank system. The 3D beam scanning process is cumbersome, labor intensive, error-prone, and costly. This is especially challenging for the new Ethos system and MR Linacs with a ring gantry. This work proposes an alternative approach to verify 6FFF beam dosimetry for Ethos, ViewRay MRIdian® Linac, and other Linacs with 6FFF beam quality using two-dimensional (2D) ion chamber arrays. Methods Percentage depth dose (PDD) and profiles of an Ethos, an MRIdian® Linac, and several Linacs with 6FFF beams were measured at the nominal beam current. The beam energy was detuned by changing the bending magnet current on one TrueBeam. PDDs and profiles were measured for detuned beam energies. The peak shape of the 6FFF profile was defined by a "slope" parameter and unflatness. Correlations between peak slope and unflatness metrics vs PDDs were used to evaluate the sensitivity of beam energy to beam profile changes at different field sizes and depths. Results Strong correlations were found between peak slope and PDDs for all Linacs with 6FFF beam. The R-squared values in the linear regression fitting between PDD and peak slope and unflatness were 0.99 and 0.84, respectively. Both profile slope and unflatness were proportional to PDD at the 10 cm depth and the peak slope was 4.3 times more sensitive than PDD. We have identified that measurements with a shallow depth are preferred to quantify the beam energy consistency. Conclusions Our work shows the feasibility of verifying 6FFF beam quality of Ethos, MR Linac, and other Linacs by defining a profile slope measured from 2D ionization chambers array devices. This new approach provides a simplified method for performing a routine beam quality check without using a 3D water tank system while maximizing cost effectiveness and efficiency.
Pre-column derivatization with fluorescamine and high-performance liquid chromatographic analysis of drugs. Application to tocainide.

Abstract The quantitative determination of tocainide, a new antiarrhythmic agent, by high-performance liquid chromatography (HPLC) is reported. The drug and a chemically similar internal standard were extracted from blood plasma with acetonitrile under salting-out conditions obtained by saturation of the aqueous medium with sodium chloride—sodium carbonate. The organic extract, without evaporation, was treated with borate buffer (pH 8.2) and fluorescamine. The resulting derivatives were chromatographed on an ODS reversed-phase column using a methanol—phosphate buffer (pH 7.0) mixture as mobile phase and were detected fluorometrically by monitoring the emission at 485 nm, with excitation at 395 nm. The intra-assay coefficients of variation were 3.0 and 4.3% for ten replicate 0.25 and 1.00 μg/ml samples, respectively, and the inter-assay coefficient of variation was 3.6% for ten replicate 1.00 μg/ml samples. The procedure is simple, rapid, sensitive, and specific. Several other drugs and drug metabolites also were derivatized with fluorescamine and chromatographed successfully. Pre-column derivatization with fluorescamine followed by HPLC with fluorometric detection may have significant advantages in drug analysis.
Self-aligned carbon nanotube transistors with novel chemical doping

We report an unconventional chemical p- and n- doping scheme utilizing novel materials and a charge transfer mechanism to obtain air-stable, self-aligned, unipolar carbon nanotube transistors. This scheme in addition to introducing the tunability of the threshold voltage V/sub th/, increases the drive current 2-3 orders of magnitude, transforms CNFET from ambipolar to unipolar, suppresses minority carrier injection and yields an excellent I/sub on//I/sub off/ ratio of 10/sup 6/.
Inhibition of cell-matrix adhesions prevents cartilage chondrocyte death following impact injury

Focal adhesions are transmembrane protein complexes that attach chondrocytes to the pericellular cartilage matrix and in turn, are linked to intracellular organelles via cytoskeleton. We previously found that excessive compression of articular cartilage leads to cytoskeleton-dependent chondrocyte death. Here we tested the hypothesis that this process also requires integrin activation and signaling via focal adhesion kinase (FAK) and Src family kinase (SFK). Osteochondral explants were treated with FAK and SFK inhibitors (FAKi, SFKi, respectively) for 2 h and then subjected to a death-inducing impact load. Chondrocyte viability was assessed by confocal microscopy immediately and at 24 h post-impact. With no treatment immediate post-impact viability was 59%. Treatment with 10 µM SFKi, 10 μM, or 100 µM FAKi improved viability to 80%, 77%, and 82%, respectively (p < 0.05). After 24 h viability declined to 34% in controls, 48% with 10 µM SFKi, 45% with 10 µM FAKi, and 56% with 100 µM FAKi (p < 0.01) treatment. These results confirmed that most of the acute chondrocyte mortality was FAK- and SFK-dependent, which implicates integrin-cytoskeleton interactions in the death signaling pathway. Together with previous findings, these data support the hypothesis that the excessive tissue strains accompanying impact loading induce death via a pathway initiated by strain on cell adhesion receptors.
Probable tubal origin of endometriosis

Abstract It has been pointed out that an adenomatous formation composed of either tubal epithelium or endometrium, or in a few cases of both simultaneously, occurs rather frequently in the region of the uterine cornu and tubal isthmus. A previous operative trauma of this region is not essential for the production of such an adenomatous formation, nor is it necessarily associated with any previous inflammatory process. It may be considered then as a truly neoplastic formation or primary adenomyoma. From the types of epithelium described in these adenomyomas it is evident that they may arise from tubal epithelium as well as endometrium. The presence in a few cases of spaces lined by tubal epithelium as well as islands of true endometrium in the same specimen suggests the possibility of a metaplasia of one of these types of mucosa into the other. The finding of gland-like spaces lined by tubal epithelium but surrounded by endometrial stroma is even more suggestive of this possibility. The finding of ten cases in which the interstitial or isthmic portion of the tube is lined by endometrium rather than tubal mucosa is further evidence of the histologic variability of this region, and suggests again the possibility of a metaplasia of one of these types of mucosa into the other. Evidence gathered from the literature, particularly from the work of Sampson, tends to show that a number of cases reported as endometriosis are really cases of aberrant tubal epithelium. It is noted, however, that Sampson has called attention to this fact from time to time, and in a more recent work on “Endometriosis Following Salpingectomy” has stressed the probability of a metaplasia of tubal mucosa into endometrium. In a review of 24 cases diagnosed as endometriosis in our own laboratory it has been found that in a third of them the epithelial elements were definitely tubal in type. In some of them there was in addition to the tubal epithelium an endometrial-like stroma. In a few instances cysts lined by tubal epithelium and others with real endometrium occurred in the same case. In one very striking case the same hemorrhagic cyst of an ovary was lined in part by tubal epithelium, while another area of the cyst wall showed real endometrium with stroma and glands. Such cases lend additional evidence to the hypothesis that tubal epithelium may, by metaplasia, be transformed into endometrium.
Real Analysis: An Introduction To The Theory of Real Functions and Integration

PART I. AN INTRODUCTION TO GENERAL TOPOLOGY SET-THEORETIC AND ALGEBRAIC PRELIMINARIES Sets and Basic Notation Functions Set Operations under Maps Relations and Well-Ordering Principle Cartesian Product Cardinality Basic Algebraic Structures ANALYSIS OF METRIC SPACES Definitions and Notations The Structure of Metric Spaces5 Convergence in Metric Spaces Continuous Mappings in Metric Spaces Complete Metric Spaces Compactness Linear and Normed Linear Spaces ELEMENTS OF POINT SET TOPOLOGY Topological Spaces Bases and Subbases for Topological Spaces Convergence of Sequences in Topological Spaces and Countability Continuity in Topological Spaces Product Topology Notes on Subspaces and Compactnes Function Spaces and Ascoli's Theorem Stone-Weierstrass Approximation Theorem Filter and Net Convergence Separation Functions on Locally Compact Spaces PART II. BASICS OF MEASURE AND INTEGRATION MEASURABLE SPACES AND MEASURABLE FUNCTIONS Systems of Sets System's Generators Measurable Functions MEASURES Set Functions Extension of Set Functions to a Measure Lebesgue and Lebesgue-Stieltjes Measures Image Measures Extended Real-Valued Measurable Functions Simple Functions ELEMENTS OF INTEGRATION Integration on C -1(W,S) Main Convergence Theorems Lebesgue and Riemann Integrals on R Integration with Respect to Image Measures Measures Generated by Integrals. Absolute Continuity. Orthogonality Product Measures of Finitely Many Measurable Spaces and Fubini's Theorem Applications of Fubini's Theorem CALCULUS IN EUCLIDEAN SPACES Differentiation Change of Variables PART III. FURTHER TOPICS IN INTEGRATION ANALYSIS IN ABSTRACT SPACES Signed and Complex Measures Absolute Continuity Singularity Lp Spaces Modes of Convergence Uniform Integrability Radon Measures on Locally Compact Hausdorff Spaces Measure Derivatives CALCULUS ON THE REAL LINE Monotone Functions Functions of Bounded Variation Absolute Continuous Functions Singular Functions BIBLIOGRAPHY
Reduced Nicotinamide Adenine Dinucleotide Phosphate-Sulfite Reductase of Enterobacteria VI. THE REACTION OF CARBON MONOXIDE WITH THE ESCHERICHIA COLI HOLOENZYME, THE HEMOPROTEIN, AND FREE SIROHEME

Abstract Escherichia coli NADPH-sulfite reductase (EC 1.8.1.2) is composed of hemoprotein and flavoprotein subunits. The heme prosthetic group, responsible for interactions of the enzyme with sulfite, is a novel octacarboxylate iron-tetrahydroporphyrin of the isobacteriochlorin type, which has been given the name siroheme. Rate constants for the formation (kon) of E. coli sulfite reductase-CO complex and E. coli sulfite reductase hemoprotein-CO complex have been measured. The kon for the native reduced enzyme and its hemoprotein subunit had values of 6.9 m-1 s-1 and 7.7 m-1 s-1, respectively. Such kon values are extremely slow when compared to those of other hemoproteins such as hemoglobin and cytochrome oxidase. However, the isolated siroheme prosthetic group, in the absence of protein, exhibited a kon for CO complex formation of 1 x 107 m-1 s-1, a value comparable to those found for other free hemes; the siroheme-CO complex was photodissociable. No dissociation of the holoenzyme or hemoprotein-CO complexes could be detected under reducing conditions. A very slow dissociation (koff = 6.2 x 10-5 s-1 for holoenzyme-CO and 9.2 x 10-5 s-1 for hemoprotein-CO) of CO from its complexes with enzyme could be detected aerobically, with formation of oxidized heme-enzyme. In contrast to siroheme-CO, no photodissociation of holoenzyme-CO complex was detected. It is concluded that the rates of association and dissociation of carbon monoxide with sulfite reductase reflect profound hindering effects exerted on the heme by its immediate environment in the hemoprotein subunit, and are not due to constraints imposed by either the flavoprotein portion of the holoenzyme or by the unusual structure of the iron-tetrahydroporphyrin itself.
Open issues in MPI implementation

MPI (the Message Passing Interface) continues to be the dominant programming model for parallel machines of all sizes, from small Linux clusters to the largest parallel supercomputers such as IBM Blue Gene/L and Cray XT3. Although the MPI standard was released more than 10 years ago and a number of implementations of MPI are available from both vendors and research groups, MPI implementations still need improvement in many areas. In this paper, we discuss several such areas, including performance, scalability, fault tolerance, support for debugging and verification, topology awareness, collective communication, derived datatypes, and parallel I/O. We also present results from experiments with several MPI implementations (MPICH2, Open MPI, Sun, IBM) on a number of platforms (Linux clusters, Sun and IBM SMPs) that demonstrate the need for performance improvement in one-sided communication and support for multithreaded programs.
Comparative Performance of Alcohol and Hydrocarbon Fuels

Calculated and experimental comparative performance characteristics of alcohols (methanol and ethanol) and hydrocarbons (octane and benzene) as spark ignition engine fuels are presented. These characteristics were derived from analysis of relative amounts of combustion products produced per unit of inducted charge, energy in the charge, and latent heat of evaporation. The thermodynamic properties of methanol and air, ethanol and air, and benzene and air were also analyzed. Differences in the stoichiometry and thermochemistry of the hydrocarbons and alcohols confirm the observed increase in power output with ethanol and methanol, in particular, as engine fuels. Accompanying any increase in output is a disproportionate rise in fuel consumption. Principal factors influencing output are the product volume/inducted charge volume and the fuel latent heat as it may influence compression work. More sophisticated analysis, based upon thermodynamic charts of combustion products, do not necessarily improve correspondence between calculated and experimental results.
Cell Death: Critical Control Points

Programmed cell death is a distinct genetic and biochemical pathway essential to metazoans. An intact death pathway is required for successful embryonic development and the maintenance of normal tissue homeostasis. Apoptosis has proven to be tightly interwoven with other essential cell pathways. The identification of critical control points in the cell death pathway has yielded fundamental insights for basic biology, as well as provided rational targets for new therapeutics.
A broadcast/reduce architecture for high-speed data compression

The author presents a parallel architecture for high-speed data compression based on textual substitution using a sliding window. The architecture combines a systolic array with trees for data broadcast and reduction. Compression involves two steps. First, a match generator computes in parallel the maximal matches available at each position of the input. The generator uses a systolic array to hold the dictionary, a pipelined broadcast tree to deliver each input character simultaneously to every array cell, and a reduction tree to identify the largest available match each cycle. From this information a second process selects a match sequence exactly covering the input. Decoding mirrors encoding. The tree interconnect provides through-delay proportional to the log of the dictionary size, and pipelining reduces the effective per-character processing time to a single system cycle. A system data rate of 300 Mbit/sec is easily attainable. The author discusses layout issues arising from the tree interconnect. >
Infants' integration of featural and numerical information.

The current study examined the integration of non-numerical (featural) and numerical information in 9-, 11-, and 13-month-old infants’ performance on a number discrimination task. Infants were habituated to pictures of objects (e.g., bowl, shoe) either in groups of two or three. In the test phase, infants saw both new and old objects in both groups of two and three. Nine-month-old infants discriminated number independent of the familiarity of the object, 11-month-old infants discriminated between familiar and novel objects (but not the number of objects), and 13-month-old infants discriminated between the familiar and novel objects only in the context of a familiar number of objects. These data suggest that early number representations are dissociated from featural information, and that the integration of these stimulus properties is a developmental process that occurs across the first year.
Experimental analysis of a passively tuned actuator on a low-order structure

This paper presents results of a study of the interaction between a passively tuned reaction mass actuator and a low-order structure. The actuator was passively tuned to the structure's first resonant frequency, and the uncontrolled and passively damped structural responses were compared. While introducing a new mode in the system, the actuator significantly reduced the peak amplitude ratios of the first two structural modes. The peak amplitude ratios of the structure's higher modes were reduced as well. A sensitivity analysis of the actuator's tuning showed that the passively damped system's resonant modes were altered if the actuator was not tuned to the optimum frequency and damping ratio. Finally, the actuator reduced the magnitude of the structural vibrations, not only where the actuator was attached to the structure, but at all points on the structure.
Implementation of a-type multistep methods for stiff differential equations

The α-type multistep methods have the form of Yn+kαnYn+k-1+(αn-1)Yn+k-2=hn+kΣi=0kβi,nfn+1 where 0 < αn < 2. They are stable for all order and step size changing sequences when implemented in a variable coefficient form. This paper will discuss some of the results of when these methods are applied to stiff differential equations.
Methylphenidate and Comorbid Anxiety Disorder in Children With Both Chronic Multiple Tic Disorder and ADHD

Objective: To determine if comorbid anxiety disorder is associated with differential response to immediate release methylphenidate (MPH-IR) in children with both ADHD and chronic multiple tic disor...
Group Incentives and Task Performance: An Information Asymmetries Perspective

Although financial incentives are widely used, their effectiveness has been debated in both the academic literature and in the popular press. More specifically, while there is general consensus that paying for performance (PFP) can serve to increase effort and productivity, there is much greater debate regarding the relationship between PFP and performance quality and/or creativity. Thus, the wisdom of using extrinsic motivators to enhance performance quality and creative decision-making -- especially important in complex, interdependent work teams found in many organizations today -- remains in doubt. Using an information asymmetries framework, we argue that group PFPs may encourage more effort in the form of greater time devoted to task-focused discussion. Based on existing research, we further suggest that greater discussion will yield higher performance quality due to more effective knowledge sharing and integration. We test these arguments in an experiment using a complex task in which relevant, crit...
Structure and spectroscopic properties of [di(3-aminopropyl)amine-N,N′,N″][iminodiacetato-N,O,O′]chromium(III) perchlorate

Abstract The mixed-ligand complex [Cr(dpt)(ida)]ClO4·2H2O (dpt=di(3-aminopropyl)amine, H2ida=iminodiacetic acid) adopts a structure in which the ligands are tridentate and coordinate facially, with the imino nitrogen trans to the dpt secondary amine. Thus the preference of iminodiacetate for facial coordination prevails over the preference of di(3-aminopropyl)amine for meridional coordination. The crystal structure of the title complex has been determined: space group Pbca; a=17.609(2), b=14.762(2), c=14.423(2) A, Z=2. An analysis of the 4Azg→{2Eg, 2T1g} electronic spectrum shows the iminodiacetate carboxylate groups to be moderately strong σ and π-donors.
Erbium:YAG laser resonator which reduces laser damage to the cavity high reflector

A rod of solid state gain material centered between two flat end mirrors (i.e. the flat-flat resonator) is a common laser resonator configuration. Positive dioptric power in the rod, thermally induced by the pumping of the gain medium, enables the resonator to operate in the stable regime. A typical problem that may ultimately limit maximum power in lasers of this type is the susceptibility of the cavity end mirrors to laser-induced damage. A technique that mitigates this damage by increasing the intra-cavity spot width at the end mirror location is described. The resulting modified resonator is equivalent to the flat-flat resonator with regard to its output laser beam propagation parameters and to the symmetrical mode fill of the gain medium.
MRI evaluation of the sphenoid sinus after transsphenoidal approach to the pituitary.

The transsphenoidal approach to the pituitary (TSA) is currently the most common approach used to treat pituitary tumors. The surgical technique necessitates an incomplete stripping of sphenoid sinus mucosa. Long-term postoperative magnetic resonance imaging (MRI) evaluation of the sphenoid sinus has not been reported. A retrospective review of patients undergoing a TSA at the University of Washington Hospitals was performed. Preoperative scans were compared with postoperative scans done during three time intervals. Group 1 had scans at 1 to 12 weeks postoperatively; 10 of 10 patients had sinus effusions. Group 2 had scans at 6 to 18 months postoperatively; 22 of 31 had mucosal abnormalities
Detection of peptidyl-3,4-dihydroxyphenylalanine by amino acid analysis and microsequencing techniques

3,4-Dihydroxyphenylalanine (DOPA) is an amino acid that occurs naturally in the primary sequence of many proteins and peptides. Detection of peptidyl-DOPA, however, can be elusive. This is due (i) to its coelution with leucine on most of the ion exchangers used in amino acid analysis and (ii) to the coelution of phenylthiohydantoin (PTH)-DOPA with PTH-alanine during routine C18 reversed-phase HPLC following automated Edman degradation. By application of appropriately timed temperature and/or gradient modifications during chromatography, DOPA and its PTH derivative can be adequately resolved for detection by both amino acid analysis and gas-phase sequencing.
All-Reflective Spatial Heterodyne Spectroscopy: Progress and Prospects

The all-reflective SHS provides wide-field, high-resolution, high-etendue remote sensing over a range of wavelengths extending into the ultra-violet. This presentation describes the basic design for the reflective SHS and both narrow and broadband applications under development.
Lifetime weight cycling and psychological health in normal-weight and overweight Women

Objective The relationship between weight cycling history and psychological health was studied in a sample of 429 normal-weight and overweight women. Method: Participants were from the Healthy Women Study, a longitudinal investigation of biological and psychosocial aspects of menopause. Participants were asked to report retrospectively details on their weight cycling history in terms of the frequency and magnitude of previous weight loss episodes. Data were examined using the total cycle weight lost and the frequency of weight cycles ⩾10 lb. Self-reported measures of depression, stress, anxiety, and anger were used to evaluate psychological health. Results: For both normal-weight and overweight women, the analyses revealed no adverse relationships between weight cycling history and the psychological measures. Discussion: These findings suggest that a history of weight cycling regardless of weight status does not adversely impact psychological health. © 1998 by John Wiley & Sons, Inc. Int J Eat Disord 24: 175–183, 1998.
On the Information Content of Umkehr Observations.

Abstract Principal component analysis has been used to determine the number of linearly independent pieces of information that may be inferred from Umkehr observations. The analysis indicates that there are at most four such pieces of information in each Umkehr curve. A simple physical explanation is given for this result. The linearized evaluation method of Dutsch (1959) has been examined by eigenvalue analysis to determine the number of pieces of information that may be computed from the system. The result of the statistical analysis is confirmed, viz., that there are at most four pieces of information about the vertical distribution of ozone to be determined. In particular, there is no possibility of determining, from Umkehr observations, whether or not there exists a secondary maximum of ozone concentration in the lower stratosphere. Methods of obtaining smoothed vertical distributions are discussed and it is pointed out that the distributions obtained are not invariant under different scalings of the...
Homogeneous Line Width of the Different Vibronic Bands of Retinal Absorption in Bacteriorhodopsin by the Hole-Burning Technique

Using the hole-burning technique, resolved vibrational structure was observed in the retinal absorption spectrum of bacteriorhodopsin (bR) in poly(vinyl alcohol) (PVA) film at 10 K with 556 and 632 nm irradiation. The homogeneous line widths of v = 1 and v = 2 vibronic bands are estimated from the deconvolution of the observed spectrum. The absorption maximum is found to shift by 100−200 cm-1 by using the two excitation wavelengths; resulting from partial site selection due to the contribution of inhomogeneous broadening. The hole width produced by excitation near the zero-phonon band is found to be ∼1250 cm-1, which corresponds to a homogeneous width of ∼600 cm-1, and the low limit of dephasing time can be estimated as 20 fs. This width is found to be independent of the vibronic band observed.
Design analysis and improvement of an IGBT gate drive circuit for magnet power supplies using a physics-based circuit model

This paper presents the design analysis and improvement of an Insulated Gate Bipolar Transistor (IGBT) gate drive circuit for the magnet power supplies of accelerator systems. By exploring the effects of the gate driving current and resistance, a low noise gate driver was developed and evaluated. The dv/dt and di /dt values that affect voltage and current spikes are modeled through the physics-based circuit model. With the improvement of a gate driver, the power supply achieved 87% efficiency at a load current of 460A with 20kHz switching, resulting in a 60% reduction of turn-off switching noise. For effective validation, the proposed gate drive circuit was simulated through the physics-based circuit model, and implemented and tested*.
Uniform analyticity and exponential decay of the semigroup associated with a thermoelastic plate equation with perturbed boundary conditions

Abstract In a bounded domain, we consider an Euler–Bernoulli-type thermoelastic plate equation with perturbed boundary conditions. The boundary conditions are such that when the perturbation parameter goes to infinity, we recover the hinged boundary conditions, while one recovers the clamped boundary conditions when the perturbation parameter goes to zero. Relying on resolvent estimates, we show that the underlying semigroup is uniformly, with respect to the perturbation parameter, analytic and exponentially stable. The main features of our proof are appropriate decompositions of the components of the system and the use of Lionsʼ interpolation inequalities.
Systems engineering: evolution and challenges

In this paper, we investigate the evolution of systems engineering using a framework developed for this purpose. Systems engineering was conceived to deal with complex problems and has evolved to address new challenges as they have emerged. The field has made advances in design capabilities and the process by which products are brought to realisation. It has worked at the limits of what is possible under an engineering governed paradigm. More challenges that involve extremely large, complex structures and networks include problems that supersede any form of design capability. The integration of a management-governed paradigm has become necessary. At this point, it is critical to map the future of systems engineering as a discipline that is capable of dealing with these new problems or can effectively limit itself to more traditional engineering undertakings.
On Fitting Generalized Linear Mixed-effects Models for Binary Responses using Different Statistical Packages

The generalized linear mixed-effects model (GLMM) is a popular paradigm to extend models for cross-sectional data to a longitudinal setting. When applied to modeling binary responses, different software packages and even different procedures within a package may give quite different results. In this report, we describe the statistical approaches that underlie these different procedures and discuss their strengths and weaknesses when applied to fit correlated binary responses. We then illustrate these considerations by applying these procedures implemented in some popular software packages to simulated and real study data. Our simulation results indicate a lack of reliability for most of the procedures considered, which carries significant implications for applying such popular software packages in practice.
Constrained LQR problems in elliptic distributed control systems with point observations-convergence results

In this paper constrained LQR problems in distributed control systems governed by the elliptic equation with point observations are studied. A variational inequality approach coupled with potential theory in a Banach space setting is adopted. First the admissible control set is extended to be bounded by two functions, and feedback characterization of the optimal control in terms of the optimal state is derived; then two numerical algorithms proposed in [5] are modified, and the strong convergence and uniform convergence in Banach space are proved. This verifies that the numerical algorithm is insensitive to the partition number of the boundary. Since our control variables are truncated below and above by two functions inL p and in our numerical computation only the layer density not the control variable is assumed to be piecewise smooth, uniform convergence guarantees a better convergence. Finally numerical computation for an example is carried out and confirms the analysis.