cssi/SciSciGPT-SciSciNet huggingface dataset:
Natural Zeolites and Nuclear-Waste Management: The Case of Yucca Mountain, Nevada, USA

The most important radionuclide migration issues at Yucca Mountain concern not 137Cs and 90Sr but anionic species and long-lived actinides that often form large, complex aqueous species. Zeolites do not interact strongly with such species, illustrating their limitations in real-world applications. Emplacement of radioactive waste will heat large volumes of rock, and zeolites will be important sources and sinks of water and thermal energy during heating and cooling in the vadose zone. In addition, dehydration/hydration reactions are accompanied by volumetric changes. Longer-term reactions, e.g., of clinoptilolite to analcime, will give rise to larger volume reductions and production of water and silica. These studies of Yucca Mountain show that the importance of zeolites extends far beyond cation exchange by zeolites to phenomena affecting the entire thermohydrologic system.
Mechanisms of Control in the Coronary Circulation

The purpose of this brief introductory review is to place into perspective the relative importance of several mechanisms that regulate myocardial perfusion. I will also discuss some older concepts that have been the subject of stringent criticism and new developments in research concerning regulation of myocardial perfusion.
ORGANIC TRACERS FROM WILD FIRE RESIDUES IN SOILS AND RAIN/RIVER WASH-OUT

The molecular compositions and alteration products of the major organic components in soils and litter subjected to controlled or wildfire burning, and subsequent erosion by rain and river transport have been determined by GC-MS. The major compound groups imparted to soils include n-alkanoic acids, n-alkanes, n-alkanols, phytosterols, and terpenoids. Biomarker tracer analysis indicates that organic compounds remain as internal lipid components of char and heavy particles and are deposited onto soil during wildfire and prescribed burning. The process of rain erosion and river transport releases some of these internal components into the surroundings where they are further subjected to biological alteration. The distributions and abundances ofhomologous compound series coupled with biomarker tracer analysis provides a chemical fingerprint which is useful for identifying the single or multiple plant species contributing organic matter by both thermal (burning) and biological processes. Such fingerprints are useful for tracking soils which are transported in the atmosphere by wind as suspended particles in dust storms and on land by rain erosion to rivers.
Determination of fish flesh content in frozen coated fish products (modification of AOAC Official Method 971.13) : Collaborative study

An intralaboratory collaborative study evaluated a modified version of AOAC Official Method 971.13 for determining the fish flesh content (FFC) in frozen coated fish products by comparing it with the on-line method. Eleven collaborators analyzed 36 products (a total of 6336 test samples). Each product targeted one of 4 percent fish flesh (PFF) levels (35, 50, 65, and 80). Products were manufactured from one of 3 raw materials (fillet blocks, minced blocks, and natural fillets) and processed in one of 4 forms (sticks, portions, formed portions, and fillets) and one of 4 styles (raw breaded, batter-dipped, precooked, and fully cooked). Each "official" test sample was tracked through the processing system and weighed (1) before battering and/or breading and, depending on product style, before frying; and (2) after battering and/or breading and, depending on product style, after frying; so that it served as its own control. These weights were used to calculate actual percent fish flesh (APFF) and considered to be generated by the on-line method. Collaborators weighed official test samples (1) before scraping; and (2) after scraping. These weights were used to calculate determined percent fish flesh (DPFF) and considered to be generated by the modified AOAC method. APFF and DPFF were the primary data for statistical analysis. Recoveries ranged from 71.75 to 106.40%. Repeatability (method precision indicator for a single collaborators) relative standard deviation (RSDr) values ranged from 1.04 to 8.37%. Corresponding reproducibility (method precision indicator among collaborators) relative standard deviation (RSDR) values ranged from 1.41 to 11.95%. The DPFF mean was lower than the APFF mean for 30 (83.3%) of 36 products. For 29 of these 30 products, the differences between method means (APFF minus DPFF) ranged from 0.38 to 6.51%. For the remaining product within this group (C/06, fillet blocks, fully cooked portions), the difference between method means was 21.73%. For the remaining 6 (16.67%) of 36 products, the DPFF mean was greater than the APFF mean. The differences between method means ranged from -0.03 to -2.76%. RSD values were considered acceptable (i.e., RDSr < 9% and RSDR < 12%) for all products studied. The modified method for determining FFC in frozen coated fish products has been adopted first action to replace AOAC Official Method 971.13.
International Student Achievement Comparisons and US STEM Workforce Development

Comparisons of US student achievement to other countries, conducted since the 1960s, have received extensive media coverage in the USA. Policy studies have cited these comparisons as evidence that the quality of US educational performance in mathematics and science requires federal intervention. Policy makers have been particularly concerned that the US economy would be impacted by inadequate student achievement levels especially in technology-related industries. This paper explores evidence about whether policy makers react to the citations of international student achievement rankings by changing funding levels for educational research and whether the studies have motivated the nation’s educators to support a trend toward common educational standards.
Physics and Astronomy Experiences Using Personal Response Systems

We report on the use of personal response systems (such as I-Clicker) as a real-time assessment tool utilized during a course lecture period.Â The presenters utilized two different personal response systems in their conduct of classes at the 100 and 200 level.Â Ehrlich reports on the utilization of an infrared system in his physics course.Â Geller reports on the utilization of a radio frequency system in his introductory astronomy course.Â The latter system will be utilized during the workshop as part of the audience's participation in demonstrating the utility of personal response systems in a classroom setting.
Autophagy and cardiac aging

Cardiovascular disease (CVD) is the leading cause of death and the prevalence of CVD dramatically increases with age. Cardiac aging is associated with hypertrophy, fibrosis, inflammation, and decreased contractility. Autophagy, a bulk degradation/recycling system, is essential to maintain cellular homeostasis. Cardiac autophagy is decreased with age, and misfolded proteins and dysfunctional mitochondria are accumulated in the aging heart. Inhibition of autophagy leads to exacerbated cardiac aging, while stimulation of autophagy improves cardiac function and also increases lifespan in many organisms. Thus autophagy represents a potential therapeutic target for aging-related cardiac dysfunction. This review discusses recent progress in our understanding of the role and regulation of autophagy in the aging heart.
Development of MATLAB simulink model of Invelox to Analyze The Impact of Inlet Height On speed ratio

Diverse models of wind turbines are established by various researchers. Each model has its own advantage and disadvantage. One of the major problems associated with the traditional and other ducted wind turbine is the massive height and the rotating turbines which makes it difficult for maintenance. Also such wind turbines causes various environmental hazards. So a unique design of wind turbine is required to provide sustainable, high performance, affordable and cost effective electrical energy to anywhere and anyone. INVELOX is a new innovation in the wind power industry that has unique structure and has claimed to solve all the major issues associated with the current wind turbines. In this paper, MATLAB/simulink model of INVELOX is developed to determine speed ratio based on inlet height. Simulation of the development process is based on the concept of continuity principle. Analysis indicates that the proposed model is satisfactorily accurate to determine the speed ratio (SR) of the INVELOX.
Size control over metal–organic framework porous nanocrystals

Porous nanocrystals of metal-organic frameworks (MOFs) offer greater bioavailability, higher surface-to-volume ratios, superior control over MOF membrane fabrication, and enhanced guest-sorption kinetics compared to analogous bulk phases, but reliable synthesis of uniformly sized particles remains an outstanding challenge. Here, we identify the smallest and most probable sizes of known MOF nanocrystals and present an exhaustive comparative summary of nano- versus bulk-MOF syntheses. Based on critical analysis of reported size data and experimental conditions, an alternate to the LaMer model is proposed that describes nanocrystal formation as a kinetic competition between acid-base and metal-ligand reactivity. Particle growth terminates when ligands outcompete metal-ion diffusion, thereby arresting polymerization to produce kinetically trapped particle sizes. This model reconciles disparate trends in the literature and postulates that minimum particle sizes can be achieved by minimizing the relative ratios of metal-to-linker local concentrations. By identifying conditions that disfavor small nanocrystal sizes, this model also provides routes towards macroscopic MOF single crystals. A universal "seesaw" relationship between nanocrystal sizes and the concentrations of acidic surface-capping ligands provides a roadmap for achieving precise synthetic control. Best practices in synthesis, characterization, and data presentation are recommended for future investigations so that MOF nanocrystals may achieve their full potential as advanced nanomaterials.
Graph Simplification for Infrastructure Network Design

Network design problems often involve scenarios where there exist many possible routes between fixed vertex locations (e.g. building new roads between cities, deploying communications and power lines). Many possible routes in a network result in graph representations with many edges, which can lead to difficulty running computationally demanding optimization algorithms on. While producing a subgraph with a reduced number of edges would in itself be useful, it is also important to preserve the ability to interconnect vertices in a cost effective manner. Suppose there is a set of target vertices in a graph that needs to be part of any size-reduced subgraph. Given an edge-weighted, undirected graph with n vertices, set of target vertices T, and parameter \(k \ge 1\), we introduce an algorithm that produces a subgraph with the number of edges bounded by \(\min \{O(n\frac{n^{1/k}}{\left| {T}\right| }), O(n\left| {T}\right| )\}\) times optimal, while guaranteeing that, for any subset of the target vertices, their minimum Steiner tree in the subgraph costs at most 2k times the cost of their minimum Steiner tree in the original graph. We evaluate our approach against existing algorithms using data from Carbon Capture and Storage studies and find that in addition to its theoretical guarantees, our approach also performs well in practice.
A Cognitive Urban Collision Avoidance Framework Based on Agents Priority Using Recurrent Neural Network

We propose a novel cognitive collision avoidance (CA) framework for autonomous driving (AD) vehicles in urban environments. In this framework, a hybrid future trajectory predictor is developed, which consists of a static agent classifier, a recurrent neural network (RNN) based trajectory predictor and a lane-based kinematic model predictor. To fuse the outputs of different predictors, an iterative multivariate Gaussian weighted algorithm is designed to drop outliers and estimate the predicted dynamic features more reliably. Subsequently, fed in with the fused results of observed agents, together with the current dynamic features and planned trajectory of the ego vehicle, an RNN-based priority prediction engine is applied to infer the priority probabilities distribution for CA decision, which indicates the likelihood that the vehicle continue driving according to its planned trajectory. By observing surrounding agents' historical ground truth trajectory and taking the road geometry constraints into consideration, the future dynamic features, priority probabilities distribution and the CA decision can be figured out at every timestamp cognitively and adaptively. The performance of this framework is evaluated on a prototype car in multiple typical USA urban scenarios, comparing with conventional CA systems which assume constant velocity and only work when observed agents follow traffic rules, our framework alleviates these limitations and achieves encouraging results in terms of the priority distribution estimation, with a frequency >20Hz, which is capable of running in real-time.
A 25-29 GHz 64-Element Dual-Polarized/Dual-Beam Small-Cell with 45 dBm 400 MHz 5GNR Operation and High Spectral Purity

This paper presents a 25–29 GHz 64-element small-cell (RF to IF) dual-polarized/dual-beam phased-array for 5G communication systems. The small-cell includes dual-polarized antennas, sixteen 2 × 2 beamformers, a dual-channel driver (TX/RX), a dual-channel transceiver, filters, and a local oscillator (LO) on the printed-circuit board. This small-cell provides a measured EIRPPsat of 55 dBm for each polarization with 4 GHz, and 40–140 dBc single-sideband rejection at an IF of 2–8 GHz. The TX output spectrum is measured at an IF of 5 and 6 GHz, and all the spurs are < -55 dB lower than the desired RF signal at 10-dB back-off operation. A complex modulation measurement using OFDM 5GNR 64-QAM 400 MHz waveform (PAPR = 11–12 dB) is performed and a 43–45 dBm EIRP is achieved at 4-5% EVMRMS (- 28 to -26 dB) for the small-cell. To our knowledge, this is the first demonstration of a high-performance, low-spur phased-array for 25–29 GHz 5G systems.
Moving for Better Skill Match

This paper studies the connection between multidimensional skill mismatch and labor mobility decisions, and the implications on the aggregate economy thereof. We show empirically that higher skill mismatch induces workers to move to a better matched job. Moreover, labor mobility helps reduce skill mismatch, especially for those previously with high skill mismatch. An equilibrium search model featuring skill mismatch and on the job search is developed. Quantitatively, we find that (i) skill mismatch has an important role to play in affecting the labor mobility decisions, as well as the aggregate economy, (ii) about two-thirds of the total skill mismatch can be accounted for by search frictions, which explain half of the occupational mobility and cost about 1% of the aggregate output and welfare, and (iii) aggregate productivity growth has positive impact on both the skill mismatch and occupational mobility.
A Self-Adaptive 4 th -Order Filter Based on Tunable N-Path Filters

This paper presents a widely tunable bandpass filter (BPF) that can autonomously adapt its gain to the power level of signals present within its passband. Similar to outphasing amplifiers, the filter realizes reconfigurable gain by splitting the input signal using two N-path filters into two components of equal and opposite phases (±Φ). The components are then subtracted at the filter output to reconstruct the original signal with a gain value proportional to sin(Φ). For input signals below -10 dBm, the BPF behaves as a conventional 4th-order filter that is tunable from 0.4 GHz to 1.5 GHz. Above the -10-dBm limit, the filter gain decreases by approximately -10 dB for each +10-dB increase in the input power to maintain the filter output power at a limiting level of -9.4 dBm. Unlike classical adaptive filters, the tunable filter achieves a sublimiting in-band IIP 3 of +8.36 dBm and an out-of-band IIP 3 of +27 dBm. The filter is implemented in 0.18-µm CMOS and has a NF of 11 dB.
Computer Aided Engineering — The Educational Environment

The advent of inexpensive microprocessor-based computer systems signals the end of an engineering era. No longer can the practicing professional remain competitive using “hand” calculators or “slide rule” technology.
Coupling continuum dislocation transport with crystal plasticity for application to shock loading conditions

Abstract We have developed a multi-physics modeling approach that couples continuum dislocation transport, nonlinear thermoelasticity, crystal plasticity, and consistent internal stress and deformation fields to simulate the single-crystal response of materials under extreme dynamic conditions. Dislocation transport is modeled by enforcing dislocation conservation at a slip-system level through the solution of advection-diffusion equations. Nonlinear thermoelasticity provides a thermodynamically consistent equation of state to relate stress (including pressure), temperature, energy densities, and dissipation. Crystal plasticity is coupled to dislocation transport via Orowan's expression where the constitutive description makes use of recent advances in dislocation velocity theories applicable under extreme loading conditions. The configuration of geometrically necessary dislocation density gives rise to an internal stress field that can either inhibit or accentuate the flow of dislocations. An internal strain field associated with the internal stress field contributes to the kinematic decomposition of the overall deformation. The paper describes each theoretical component of the framework, key aspects of the constitutive theory, and some details of a one-dimensional implementation. Results from single-crystal copper plate impact simulations are discussed in order to highlight the role of dislocation transport and pile-up in shock loading regimes. The main conclusions of the paper reinforce the utility of the modeling approach to shock problems.
Studies on heart phosphofructokinase. Role of fructose 1,6-diphosphate in enzyme activity.

Abstract Aldolase and fructose 1,6-diphosphatase were found to inhibit phosphofructokinase. The inhibition appears to be due to the depletion of fructose-1,6-P2, the substrate of both enzymes. Inhibition of phosphofructokinase by aldolase, at pH 6.9, occurred at a much faster rate (t1/2 = 15 s) than that at pH 8.2 (t1/2 = 3 min). At pH 6.9 the inhibition can be reversed by allosteric activators, whereas at pH 8.2 only fructose-1,6-P2 reversed the inhibition by aldolase. Phosphosfructokinase activity appears to be dependent on fructose-1,6-P2. This ligand can modify the activity of phosphofructokinase by its reversal of enzyme inhibition at the allosteric site. In addition, its presence at the catalytic site appears to be essential for enzymatic activity.
Battery systems management using a goal-seeking framework

We present a decision-support framework for managing the charge and discharge operations in Battery Management Systems. Our goal-seeking system coordinates the charge and discharge operations of individual batteries in a collection without making any assumptions about the future behavior of the application. Our system allows users to implement different policies for scheduling the charge and discharge operations simply by changing the reward function to achieve different goals. By reusing standard models for batteries, we demonstrate how we superpose a simple damage model that can incorporate well-known operational heuristics. This damage model allows users to design policies that must account for one or more damaged batteries in the collection. In the future, this approach can be realized on a networked embedded platform to address energy storage needs in a variety of applications.
Evolution of Chemical Diversity in a Group of Non-Reduced Polyketide Gene Clusters: Using Phylogenetics to Inform the Search for Novel Fungal Natural Products

Fungal polyketides are a diverse class of natural products, or secondary metabolites (SMs), with a wide range of bioactivities often associated with toxicity. Here, we focus on a group of non-reducing polyketide synthases (NR-PKSs) in the fungal phylum Ascomycota that lack a thioesterase domain for product release, group V. Although widespread in ascomycete taxa, this group of NR-PKSs is notably absent in the mycotoxigenic genus Fusarium and, surprisingly, found in genera not known for their secondary metabolite production (e.g., the mycorrhizal genus Oidiodendron, the powdery mildew genus Blumeria, and the causative agent of white-nose syndrome in bats, Pseudogymnoascus destructans). This group of NR-PKSs, in association with the other enzymes encoded by their gene clusters, produces a variety of different chemical classes including naphthacenediones, anthraquinones, benzophenones, grisandienes, and diphenyl ethers. We discuss the modification of and transitions between these chemical classes, the requisite enzymes, and the evolution of the SM gene clusters that encode them. Integrating this information, we predict the likely products of related but uncharacterized SM clusters, and we speculate upon the utility of these classes of SMs as virulence factors or chemical defenses to various plant, animal, and insect pathogens, as well as mutualistic fungi.
Miss: A Coupled Model of Water Chemistry and Hydrodispersive Transport in Aquifers

The migration of non-biodegradable and non volatile pollutants in soils and sub-soils is the result of the competition between solution and particulate transport and retention by insolubilization (adsorption, precipitation). Various models, taking into account convection, dispersion and,to a lesser extent,solid-liquid interactions, have been developed in order to predict the transfer of pollutants in the pedosphere and the lithosphere. In the investigations coupling flow and solid-liquid interactions, the latter are usually accounted for by empirical expressions (partition coefficient Kd). Such an approach cannot consider the significant role played by the various dissolved chemical forms that an element can present. The dissolved concentration of an element and consequently its interactions with soils are strongly dependent upon the water chemical parameters (pH, Eh, major anions and cations, complexing agents).
Performance of buildings and serviceability of facilities: Background, and impact of presentations on standards needs

This paper summarizes the keynote addresses and panel discussions at the ASTM symposium. The development Since World War II of standards for the behavior in service of a building as a whole, or of the building components,is described. The role of ASTM Committee E06 on Performance of Building Constructions, is outlined. The need for standards as an aid to facility management is presented. Terminology is clarified. Durability and service life are considered. Standards for building performance and serviceability are described. Needs for standards are summarized.
A Review of “Introduction to Information Science”

The field of information science can be described as broad, vast, huge, and unwieldy. The authors of this book are well aware of this, which is why they are very specific in their Preface regarding...
The Cult of Efficiency in Corporate Law

This paper challenges a fundamental assumption of corporate law scholarship. Corporate law is heavily influenced by economics, and by normative economics in particular. Economic efficiency, for example, is seen as the primary goal of good corporate governance. But this dependence on standard notions of economic efficiency is unfortunate, as those notions are highly problematic. In economic theory, efficiency is spelled out in terms of individual preference satisfaction, which is an inadequate foundation for any sort of normative analysis. We argue that on any account of the good, people will sometimes prefer things that aren’t good for them on that account. Giving people what they want, then, isn’t necessarily an accomplishment, and thus the normative assessment of economic outcomes is much more complicated than economists recognize. This fact is something that should be reflected in corporate law scholarship, and would greatly expand the range of possible considerations when restructuring corporate law.
Becoming a "communal architect" in the online classroom: Integrating cognitive and affective learning for maximum effect in web-based education

The authors discuss several online and offline community-building strategies that may be used to foster a positive social dynamic in online courses. Before presenting specific strategies, they begin by introducing readers to what they refer to as "communal scaffolding." The communal scaffold lets instructors conceptualize how affective and cognitive learning are inextricably intertwined in the online learning process. It also provides a theoretical base and sets pedagogical guidelines for fostering a supportive communication climate in the online setting. As presented herein, the communal scaffold is consistent with the assumptions embedded in climate theory (popular in community and social psychology literature), which assumes that psychosocial climates vary with different settings; climates are a product of environmental and individuals characteristics; and the relationships between climate, setting, and individuals are reciprocally influential (Pargament, et al., 1983).
The new dependency: Technological change and socioeconomic restructuring in Latin America

This article analyzes the implications for the Latin American societies of the ongoing restructuring of the world economy, which is driven by the accelerated application of science and technology to the production process. After a short review of the current developments at the regional level, the article focuses on Mexico and Bolivia. These two extreme cases, ranging from high-technology industries on the United States-Mexico border to the growth of an underground economy based in the production of coca and cocaine, allow the analysis of new forms of dependency that are already constraining the economic adjustment and the democratization process in Latin America.
De la méditation sur le crâne à la représentation de soi-même à l’heure de la mort : Dans la poésie et la pensée de l’âge baroque en France

Le reveil de l’ardeur morale a l’âge baroque se traduisit en autres par l’apparition d’un nouveau discours sur la mort, le quotidie morior, lequel requiert une constante preparation a la mort par le biais de divers exercices spirituels propres a familiariser les hommes avec l’idee de la mort, a leur en rappeler l’imminence, et a les tenir constamment dans l’etat le plus propice a l’accueillir. La meditation sur le crâne et les efforts de vision apriorique du ceremonial de sa propre mort sont au nombre de ces exercices, qui s’inscrivent dans le cadre general d’un humanisme devot operant une solide synthese entre dogmes anciens et morale chretienne, et conferant ainsi, au nom d’une morale pratique ou utilitaire, leurs fondements rationnels ou mystiques a certaines vieilles conceptions ideologiques.
RNA-dependent replication, transcription, and persistence of brome mosaic virus RNA replicons in S. cerevisiae

Abstract This paper shows that yeast can be a host for the replication of a higher eukaryotic viral genome. Brome mosaic virus (BMV) is a member of the alphavirus-like superfamily of animal and plant positive strand RNA viruses. Yeast expressing BMV RNA replication genes 1a and 2a support RNA-dependent replication and transcription of BMV RNA3 derivatives. RNA3 derivatives with the coat gene replaced by a reporter gene expressed that gene in a fashion dependent on 1a and 2a expression in trans and on BMV RNA replication and transcription signals in cis. RNA3 derivatives carrying the yeast URA3 gene complemented ura3 − yeast to prototrophy and were maintained as persistent RNA episomes. Thus, all cellular factors essential for BMV RNA replication and transcription must be present in yeast, and yeast genetics should facilitate their identification.
Knowledge-Based Decision Support by CRITIC

A knowledge-based diagnostic model which helps decisionmakers learn about hidden liabilities in their plan scenarios is developed in this paper. It offers critical opinions on plan deficiencies that may otherwise remain undetected. Decisionmakers preserve the freedom to explore solutions and retain the authority of making adjustments. This approach to human–computer interface design contributes to a more advanced domain-specific decision support system.
STRUCTURE OF THE SIDE-BY-SIDE BINDING OF DISTAMYCIN TO D(GTATATAC)2

The 2.40 A resolution crystal structure of a side-by-side binding of distamycin A molecules to a DNA octamer d(GTATATAC)2 with an extended alternating TA sequence has been determined. The unit-cell parameters are a = 29.55, b = 42.18, c = 43.38 A, β = 96.56°, space group P21, with two molecules in the asymmetric unit, in contrast to all previous side-by-side distamycin–DNA complexes which have only a single DNA strand and one drug molecule in the asymmetric unit. The structure was solved by the molecular-replacement method and refined to an R index of 21.0% using 3467 reflections [≥ 2σ(F)]. The minor grooves of the DNA molecules bind two side-by-side antiparallel staggered distamycins spanning about five base pairs and virtually covering the entire length of the DNA. The octamer duplexes exhibit low–high alternations in the helical twist, sugar puckering and the C—O3′ and O3′—P torsion angles, similar to the earlier side-by-side complexes containing inosine bases. The molecules are stacked one over the other along the ac diagonal in an infinite pseudo-continuous helical column with no lateral interactions.
Phagocyticidal and antibacterial action of boric acid.

Experiments in vitro at temperatures of 37° or 40° indicate that boric acid in concentrations higher than 2 per cent inhibits phagocytosis. No inhibition is demonstrated by boric acid in concentrations below 2 per cent at these same temperatures. Several suggestions and recommendations relative to the clinical use of boric acid and based on these findings are made.
Catalysis by xanthine oxidase suspended in organic media

Abstract Milk xanthine oxidase has been found to catalyze the oxidation of crotonaldehyde when the enzyme was present as a suspension in various organic solvents. In several solvents the maximal velocities and Michaelis constants differed from those obtained for the enzyme-catalyzed reaction in aqueous solution by factors of less than tenfold.
Pharmacological characterization of alpha-adrenoceptors involved in nictitating membrane and pupillary responses to sympathetic nerve stimulation in cats

Electrical stimulation of the preganglionic cervical sympathetic nerve produced frequency-related contraction of the nictitating membrane (NM) and dilation of the pupil in anesthetized cats. Observations of the effects of alpha-adrenoceptor blockade on these effectors were made simultaneously from the same preparations. All of the alpha1 -adrenoceptor antagonists tested produced a doserelated blockade of the NM with the relative potencies being prazosin > WB-4101 > phentolamine > phenoxybenzamine. In contrast, the iris dilator response was blocked by WB-4101 and phenoxybenzamine but was almost totally refractory to antagonism by doses of prazosin and phentolamine that reduced the evoked NM responses by more than 75% in these same preparations. Neither alpha2-adrenoceptor (yohimbine or rauwolscine) nor beta-adrenoceptor (propranolol) antagonism produced significant inhibition of the activation of either organ. These results suggest that: 1) neural activation of the nictitating membrane is solely due to stimulation of alpha1 -adrenoceptors; 2) neither beta- nor alpha2-adrenoceptors contribute significantly to nerve activation of either the nictitating membrane or iris dilator muscle in vivo; 3) the alpha-adrenoceptors on the dilator muscle that are activated neurally can not be classified pharmacologically as either alpha1 or alpha2 receptors.
Therapeutic exercise in rheumatoid arthritis.

The nature of the exercise program prescribed for patients with rheumatoid arthritis at the Massachusetts General Hospital is presented with a summary of the physiologic principles involved. In future issues, similar articles will be presented giving specific details of certain aspects of therapy for the rheumatic diseases at various institutions throughout the world. Es describite le programma de exercitios in uso con patientes de arthritis rheumatoide al Hospital General Massachusetts. Le subjacente principios physiologic es summarisate. In editiones futur de iste jornal, simile articulos va esser publicate con detalios specific de certe aspectos del therapia empleate in le morbos rheumatic a varie institutiones in omne partes del mundo.
HLA-DR expression in macaque neuroendothelial cells in vitro and during SIV encephalitis

HLA-DR expression in neuroendothelial cells (NEC) was studied during the course of SIV encephalitis in rhesus monkeys. HLA-DR determinants were detected on NEC in monkeys with SIV encephalitis, but not in control animals. In situ hybridization with an SIV probe indicated that HLA-DR expression was not a consequence of SIV replication within NEC. Cultured rhesus NEC stimulated with gamma interferon expressed HLA-DR to a higher degree than cultured brain fibroblasts or astrocytes. These data support the contention that NEC participate in retrovirus-induced inflammation and autoimmunity within the central nervous system.
Mechanical properties and failure surface morphology of amine-cured epoxy/clay nanocomposites

The tensile and impact properties of amine-cured diglycidyl ether of bisphenol A based nanocomposites reinforced by organomontmorillonite clay nanoplatelets are reported. The sonication processing scheme involved the sonication of the constituent materials in a solvent followed by solvent extraction to generate nanocomposites with homogeneous dispersions of the organoclay nanoplatelets. The microstructure of the clay nanoplatelets in the nanocomposites was observed with transmission electron microscopy, and the clay nanoplatelets were well dispersed and were intercalated and exfoliated. The tensile modulus of epoxy at room temperature, which was above the glass-transition temperature of the nanocomposites, increased approximately 50% with the addition of 10 wt % (6.0 vol %) clay nanoplatelets. The reinforcing effect of the organoclay nanoplatelets was examined with respect to the Tandon–Weng and Halpin–Tsai models. The tensile strength was improved only when 2.5 wt % clay nanoplatelets were added. The Izod impact strength decreased with increasing clay content. The failure surfaces of the nanocomposites were observed with environmental scanning electron microscopy and confocal laser scanning microscopy. The roughness of the failure surface was correlated with the tensile strength. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 281–287, 2005
A High-Throughput Homogeneous Assay for Reverse Transcriptase Using Generic Reagents and Time-Resolved Fluorescence Detection

A homogeneous time-resolved fluorescence (HTRF) assay has been developed for determining the activity of HIV reverse transcriptase (HIV-RT). By using a sequential capping strategy, the assay has been configured to utilize only generic reagents such as biotinylated dUTP, streptavidin-allophycocyanin, and streptavidin-europium. The assay was optimized for a HIV-RT high-throughput screen. Under optimized conditions, a signal-to-background ratio of approximately 10:1 and a Z' factor of 0.8 were obtained. The titration curves of several known HIV-RT inhibitors have been evaluated with this assay format. This HTRF format can be used for high-throughput assays with other nucleotide polymerases.
Adhesion molecules and central nervous system inflammation

Abstract From the ever-changing acronyms and the increased grouping of molecules with different acronyms into single units, it is apparent that a general consensus on the classification of adhesion molecules has yet to be achieved. This state of flux notwithstanding, three major groups (superfamilies) of adhesion molecules exist (the immunoglobulin, integrin and selectin superfamilies), with several less well-defined groups (e.g. addressins and cadherins) waiting in the wings, not yet granted superfamily status. Just as many of the immune system-related molecules play crucial roles in leukocyte traffic within lymphoid organs, it is now apparent that the same molecules are involved in immune system cell traffic and immune-mediated damage within non-lymphoid tissues like the central nervous system (CNS). For example, inflammation is the key in lesion development in some CNS diseases and data are presented here which strongly implicate adhesion molecules in immune cell trafficking to the CNS. Although a CNS-specific homing molecule or ligand has not yet been found, some of the vascular addressins constitutive for lymphoid tissues seem to display some site-specificity during the CNS autoimmune condition experimental allergic encephalomyelitis. Understanding the molecular mechanisms underlying CNS inflammation might lead to new therapeutic strategies, e.g. treatment with anti-adhesion molecule antibodies and antibodies against soluble mediators, such as cytokines, that modulate adhesion-molecule expression. Such strategies should have broad-ranging applicability.
INTERACTION BETWEEN SOUND AND FLOW-STABILITY OF T-BURNERS.

Abstract : The question of the effect of gas flow on the damping of an acoustic cavity with an orifice is of considerable importance in connection with the experimental determination of the acoustic admittance of burning solid propellants. The present investigation considers a center-vented rigid-walled cylindrical cavity which contains burning propellant at either or both ends. The only acoustic loss mechanism considered is that of the orifice. It is found that the presence of flow will, in general, have a significant effect on the conditions necessary for the acoustic stability of such a cavity and on the interpretation of the growth and decay rates in terms of the acoustic admittances characterizing the ends of the cavity. (Author)
Importance of EPC-K1 in ischemia and reperfusion injury.

L-ascorbic acid 2-[3,4-dihydro-2,5,7,8-tetramethy-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6yl-hydrogen phosphate] potassium salt (EPC-K1) is a novel phosphate diester derivative of ascorbic acid (vitamin C) and a-tocopherol (vitaminE),whoseantioxidantpropertieshavebeenshown to lower markers of systemic inflammation as demonstrated by Shingu et al. in a recently published article in the Journal of Surgical Research [1]. Both in vivo and in vitro experiments exhibited lower levels of high mobility group box 1 (HMGB1) and inducible nitric oxide synthase (iNOS),which are normally elevated during periods of ischemic-reperfusion injuries when mice were pretreated with EPC-K1 [1]. This result agrees with several other studies that examined the effects free radical-mediated organ damage [2e18]. Knowledge of the importance of the free radical-mediated response,which is seen in cellular death associatedwith ischemic-reperfusion injuries, dates back to the 1980s [2]. Since then, a number of studies have explored the role of free radical species in several organ systems [3e12].Detrimental effects of free radicals in skeletal muscle [3e5], myocardium [6e9], and the central nervous system (CNS) [10e12] have been well documented. In all of these tissues, the administration of EPC-K1 reduced free radical-induced injuries during periods of ischemia-reperfusion. While the precise mechanism by which EPC-K1 exerts its antiinflammatory effects remains to be elucidated, part of the answer can be attributed to the chemical structure. As a derivative of vitamins C and E, EPC-K1 possesses both a hydrophilic and hydrophobic chain, rendering it soluble in both water and lipid [13]. This dual solubility enables it to react effectively by limiting various harmful effectors, including hydroxyl, alkyl, and lipid radicals [13e16]. The ability to reduce multiple types of free radicals provides insight intohowEPC-K1 is effective in limiting systemic inflammation and injury, not just organ-specific inflammation [3e12]. Cardiac cells, for example, have a tendency to producemorehydroxyl radicals as they mainly function in oxygen-rich environments. That is in stark contrast to the CNS, which consists largely of lipids and is, therefore, easily damaged by lipid radicals and peroxidation [14]. In view of these unique characteristics, EPC-K1 showcases high potential to be an effective therapeutic agent in the context of ischemia-reperfusion injuries. Wide applicability to multiple organs offers antioxidant, antiinflammatory, and cell-protective defense against free radical-mediated cellular damage. In spite of this prospect, research on EPC-K1 peaked in the mid-1990s, with diminishing interest now shown in Western countries.
Interaction with indinavir to enhance systemic exposure of an investigational HIV protease inhibitor in rats, dogs and monkeys

1. The use of a beneficial interaction between indinavir and compound A, a potent investigational HIV protease inhibitor to enhance systemic exposure of compound A, was investigated. 2. When administrated alone, compound A underwent extensive hepatic first-pass metabolism in rats and monkeys, resulting in low oral bioavailability. 3. In vitro studies with liver microsomes revealed that compound A metabolism was mediated exclusively by CYP3A enzymes in rats, dogs and monkeys. Indinavir, which also was metabolized predominantly by CYP3A enzymes, extensively inhibited compound A metabolism in microsomes, whereas compound A showed weak inhibitory potency on indinavir metabolism. 4. Consistent with in vitro observations, co-administration of the two compounds resulted in a 17-fold increase in oral AUC of compound A in rats owing to the inhibition of metabolism of compound A by indinavir, whereas compound A did not affect indinavir metabolism as indicated by the unchanged indinavir AUC. Similarly, the systemic exposure of compound A in dogs and monkeys was increased substantially following oral co-administration with indinavir by 7- and > 50-fold, respectively. 5. Enhancement in compound A systemic exposure by indinavir in humans, as predicted based on the in vivo animal and in vitro human liver microsomal data, was confirmed in subsequent clinical studies.
Detection of IgG-class antibodies to measles, mumps, rubella, and varicella-zoster virus using a multiplex bead immunoassay ☆

Serologic testing for measles, mumps, rubella, and varicella (MMRV) IgG is traditionally performed by immunofluorescence assay or enzyme immunoassay (EIA). Although sensitive and specific, these methods are labor intensive, time consuming, and require separate assays for each analyte. This study evaluated the performance of the MMRV IgG AtheNA Multi-Lyte® assay using nonclinically characterized serum specimens submitted to our laboratory for routine MMRV IgG testing. Mumps (n = 492) or rubella (n = 500) IgG were initially tested by enzyme-linked fluorescent antibody (ELFA), whereas measles (n = 494) or varicella (n = 497) were analyzed by EIA. Each sample was also tested by the AtheNA Multi-Lyte assay. Discordant results were retested by the predicate method and the multiplex assay, with further discrepancies being arbitrated by a third test. Compared to EIA/ELFA for MMRV IgG, the AtheNA assay demonstrated an overall agreement of 97.4%, 98.2%, 97.6%, and 100%, respectively. Use of this multiplex assay allows for the simultaneous detection of MMRV IgG, potentially decreasing cost, sample volume requirements, aliquot errors, and hands-on testing time.
Long-range antiferromagnetism in disordered FeNiMn alloys

Abstract Neutron diffraction measurements at 77 and 298 °K reveal long-range antiferromagnetic ordering in the atomically-disordered face-centered cubic alloys with more than about 50 at. per cent Fe in the ternary series (Ni,Fe)3Mn. Consistent with these results, the Neel temperatures of these alloys, deduced from the temperature dependence of their electrical resistivities, rise from 210 to 425°K as the iron concentration increases from 50 to 75 at. per cent. An antiferromagnetic structure that conforms to the neutron diffraction polycrystal data is the collinear, tetragonal configuration previously reported for the Mn-rich Mn-Cu alloys. However, quite unlike Mn-Cu, the Fe-Ni-Mn alloys give no detectable X-ray diffraction evidence for a tetragonal (or any other) distortion of their cubic atomic arrangement. Hence, an alternative structure proposed for these alloys is one that is cubic though not collinear, the moments on four equivalent sublattices being oriented along different 〈111〉 directions such that their vector sum is zero. Both these magnetic structures are then shown to be special cases of a general set of non-collinear, tetragonal configurations which produce the same neutron diffraction pattern for a given magnitude of the average atomic moment \ gm For the (Ni,Fe)3Mn series it is found that \ gm increases from 1.1 to 1.7μB with increasing iron concentration from 50 to 75 at. per cent, which is shown to be at least in part due to an improved degree of long-range magnetic order. The results of the present work are compared and related to the unusual ferromagnetic-antiferromagnetic behavior of the more Ni-rich alloys in this ternary series and to the low-temperature antiferromagnetic structure recently reported for γ-iron.
A statistical mechanics view of quantum chromodynamics: Lattice gauge theory

Recent developments in lattice gauge theory are discussed from a statistical mechanics viewpoint. The basic physics problems of quantum chromodynamics (QCD) are reviewed for an audience of critical phenomena theorists. The idea of local gauge symmetry and color, the connection between statistical mechanics and field theory, asymptotic freedom and the continuum limit of lattice gauge theories, and the order parameters (confinement and chiral symmetry) of QCD are reviewed. Then recent developments in the field are discussed. These include the proof of confinement in the lattice theory, numerical evidence for confinement in the continuum limit of lattice gauge theory, and perturbative improvement programs for lattice actions. Next, we turn to the new challenges facing the subject. These include the need for a better understanding of the lattice Dirac equation and recent progress in the development of numerical methods for fermions (the pseudofermion stochastic algorithm and the microcanonical, molecular dynamics equation of motion approach). Finally, some of the applications of lattice gauge theory to QCD spectrum calculations and the thermodynamics of. QCD will be discussed and a few remarks concerning future directions of the field will be made.
Three-dimensional motion determination from real scene images using straight line correspondences

Abstract An experiment in determining (3D) vehicle motion in an outdoor scene using line correspondences over an image sequence is presented. The motivation of this experiment is to test how well algorithms of motion estimation work on real life outdoor scenes. Using images taken by a well calibrated camera, the experiment includes straight line extraction from intensity images, straight line matching and motion estimation using line correspondences. Many corrections and adjustments are performed on the raw image data before they are used for motion estimation, which include film distortion correction, lens distortion correction and camera alignment. The results of this experiment indicate that for the type of vehicle motion under consideration, our algorithm can obtain reasonably accurate estimates for rotation. The experiment also reveals that there is a big gap between simulation tests and real scene tests for algorithms of motion estimation.