cssi/SciSciGPT-SciSciNet huggingface dataset:
Changes in blood-brain permeability resulting from D-amphetamine, 6-hydroxydopamine and pimozide measured by a new technique.

A new technique is described for measurement of diffusion across the blood-brain barrier using intraventricularly administered68Ga-EDTA, and determining loss from the brain with a scintillation camera. Repeated injections via permanent cannulas showed that the diffusion half-time was reduced to 50% of control values after intraventricular d-amphetamine and 6-hydroxydopamine; pimozide had no effect.
Optimization of transdermal delivery using magainin pore-forming peptide

The skin's outer layer, stratum corneum, which is a thin tissue containing multilamellar lipid bilayers, is the main barrier to drug delivery through the skin. To increase skin permeability, our previous work has shown large enhancement of transdermal permeation using a pore-forming peptide, magainin, which was formulated with N-lauroyl sarcosine (NLS) in 50% ethanol-in-PBS. Mechanistic analysis suggested that magainin and NLS can increase skin permeability by disrupting stratum corneum lipid structure. In this study, our goal was to improve conditions that increase skin permeability by magainin by further optimizing the pretreatment time and concentration of magainin exposure. We found that skin permeability increased with increasing pretreatment time. Skin permeability also increased with increasing magainin concentration up to 1 mM, but was reduced at a magainin concentration of 2 mM. Enhancement of skin permeability to fluorescein (332 Da) up to 35-fold was observed. In contrast, this formulation did not enhance skin permeability to larger molecules, such as calcein (623 Da) and dextran (3000 Da).
Statistical catastrophe theory: An overview

This paper is a summary of an address given to the Conference on Frontiers of Applied Geometry. A stochastic version of catastrophe theory is presented, using stochastic differential equations. We show that there is a nontrivial relationship between the potential functions of the deterministic models and the stationary probability density functions of the stochastic models. In the second part of the paper, we use maximum likelihood theory to derive estimators for the stationary densities, and we demonstrate how to test statistical hypotheses for these models.
Porous material cleans contaminated water and could purify hydrogen

Scientists in the USA say they have developed a new way of cleansing water using a type of porous material. As this brief feature shows, they have created and characterised a porous, semiconducting aerogel which, they have discovered, is able to remove heavy metal from contaminated water. The researchers believe that it also could be used to remove impurities from hydrogen gas.
Generation of chlorofluorocarbene by dehalogenation of fluorotrichloromethane with reduced titanium. A new synthesis of 1-chloro-1-fluorocyclopropanes.

Abstract Reaction of fluorotrichloromethane with reduced titanium at 0° produces chlorofluorocarbene which adds to alkenes, giving 1-chloro-1-fluorocyclopropanes in good yield
Rethinking elective colectomy for diverticulitis: a strategic approach to population health.

Diverticulitis is one of the leading indications for elective colon resection. Surgeons are trained to offer elective operations after a few episodes of diverticulitis in order to prevent future recurrences and potential emergency. However, most emergency surgery happens during the initial presentation. After recovery from an episode, much of the subsequent management of diverticulitis occurs in the outpatient setting, rendering inpatient “episode counting” a poor measure of the severity or burden of disease. Evidence also suggests that the risk of recurrence of diverticulitis is small and similar with or without an operation. Accordingly, contemporary evaluations of the epidemiologic patterns of treatments for diverticulitis have failed to demonstrate that the substantial rise in elective surgery over the last few decades has been successful at preventing emergency surgery at a population level. Multiple professional societies are calling to “individualize” decisions for elective colectomy and there is an international focus on “appropriate” indications for surgery. The rethinking of elective colectomy should come from a patient-centered approach that considers the risks of recurrence, quality of life, patient wishes and experiences about surgical and medical treatment options as well as operative morbidity and risks.
Part-list Cuing and the Dynamics of False Recall

False recall of an unpresented critical word after studying its semantic associates can be reduced substantially if the strongest and earliest-studied associates are presented as part-list cues during testing (Kimball & Bjork, 2002). To disentangle episodic and semantic contributions to this decline in false recall, we factorially manipulated the cues’ serial position and their strength of association to the critical word. Presenting cues comprising words that had been studied early in a list produced a greater reduction in false recall than did presenting words studied late in the list, independent of the cues’ associative strength, but only when recall of the cues themselves was prohibited. When recall of the cues was permitted, neither early-studied nor late-studied cues decreased false recall reliably, relative to uncued lists. The findings suggest that critical words and early-studied words share a similar fate during recall, owing to selective episodic strengthening of their associations during study.
Dynamic programming models for multistage decision-making tasks

Abstract The dynamic programing approach for solving multistage decision-making problems is presented. A general formulation is given followed by models of deterministic, stochastic, and adaptive versions of a particular multistage decision-making problem. Seventeen subjects participated in a computer-controlled multistage decision-making task, intended for testing the adaptive model. Group and individual decisions are analyzed in terms of both an adaptive and a nonadaptive model. Extensions of the adaptive model, by adding different environmental and personal constraints, are outlined briefly.
Calreticulin Is at the Surface of Circulating Neutrophils and Uses CD59 as an Adaptor Molecule

Calreticulin, which has been proposed to be a C1q receptor on neutrophils, has neither a transmembrane domain nor a GPI-anchor attachment site and must utilize an adaptor molecule to attach to the plasma membrane. The expression of ecto-calreticulin on purified human neutrophils did not result from contamination by soluble or intracellular calreticulin released during cell fractionation because it was expressed on circulating neutrophils, and the expression did not increase significantly with neutrophil isolation. All neutrophils expressed calreticulin with a unimodal distribution. Treatment of neutrophils with either a cholesterol-binding agent or phosphatidylinositol-specific phospholipase C dramatically decreased ecto-calreticulin expression indicating that the adaptor molecule(s) are located in lipid rafts and have a GPI-anchor. Analysis for the co-expression of specific GPI-anchored proteins and ecto-calreticulin in cells that were deficient in specific GPI-anchored proteins, indicated that ecto-calreticulin was best associated with CD59. Calreticulin reciprocally immunoprecipited with CD59, which provided direct evidence that CD59 is an adaptor for ecto-calreticulin. Immunofluorescence and confocal microscopy demonstrated that ecto-calreticulin co-localized with a fraction of CD59 at the cell surface. Cross-linking ecto-calreticulin with antibodies induced a Ca2+ flux, which suggests that ecto-calreticulin is capable of signaling following ligand binding. Ecto-calreticulin has been associated with diverse cellular functions. An appreciation that the adaptors for ecto-calreticulin are GPI-anchored will provide a framework for understanding any common features underlying ecto-calreticulin ligation.
Kinetics of the reactions of the Escherichia coli molecular chaperone DnaK with ATP: evidence that a three-step reaction precedes ATP hydrolysis.

The mechanism of the ATPase cycle of the 70-kDa Escherichia coli molecular chaperone DnaK was investigated by following ATP-induced changes in the tryptophan fluorescence of DnaK. Three steps in the cycle were investigated. (i) Stopped-flow experiments revealed that ATP induces a biphasic reduction in the tryptophan fluorescence of DnaK. The rate of the fast fluorescence transition exhibited a hyperbolic dependence on the ATP concentration, with a maximum rate equal to 56 (± 10) s-1 at 35 °C, whereas the rate of the slow fluorescence transition was nearly independent of the ATP concentration (4.2 ± 0.2 s-1). These results are consistent with the three-step sequential reaction E + ATP ⇔ E−ATP ⇔ E*−ATP ⇔ E**−ATP prior to DnaK-catalyzed ATP hydrolysis, where the formation of a collisional complex (E−ATP) causes no change in fluorescence but is followed by two first-order transitions that reduce the fluorescence. (ii) The kinetics of ADP replacement from preformed DnaK−ADP complexes by ATP followed simple exp...
Human Monocyte-derived Macrophages Secrete Two Forms of Proteoglycan-Macrophage Colony-stimulating Factor That Differ in Their Ability to Bind Low Density Lipoproteins

This study evaluated whether human monocyte-derived macrophages synthesize specific types of proteoglycans with lipoprotein-binding capability that could contribute to lipid retention in the arterial wall. After labeling with either [35S]SO4 or [35S]methionine, macrophages secreted a high molecular mass proteoglycan, with glycosaminoglycan chains of approximately 18 kDa and core protein bands of approximately 100 and 55 kDa. Both core protein bands were recognized by an antibody to PG-100, an antibody that recognizes the proteoglycan form of macrophage colony-stimulating factor (PG-100/PG-MCSF). The interaction between PG-100/PG-MCSF and low density lipoproteins (LDL) was examined by gel mobility shift. In this system, PG-100/PG-MCSF was resolved further into two forms. The two forms had the same core proteins but differed in their overall size and glycosaminoglycan content. The larger form contained glycosaminoglycan chains that were entirely chondroitin ABC lyase-sensitive, whereas the smaller form contained chains that were sensitive to both chondroitin ABC lyase and heparinase. Both forms bound native LDL with high affinity, but the larger form bound LDL with higher affinity than the smaller form. The glycosaminoglycan chains of PG-100/PG-MCSF, but not the core proteins, were responsible for binding to native LDL. Mildly oxidized LDL and methyl-LDL, which have an electrophoretic charge similar to that of native LDL, also bound PG-100/PG-MCSF. In contrast, extensively oxidized LDL and acetyl-LDL, which are more electronegative than native LDL, did not bind to either form of PG-100/PG-MCSF. The demonstration of two forms of human monocyte-derived macrophage PG-100/PG-MCSF which bind LDL may represent an additional role for macrophages in the extracellular trapping of lipoproteins in atherosclerosis.
Automatic Economic Dispatching and Load Control - okio Edison System

The addition of the GEDA computer to the automatic load-frequency control has given the system efficient economic control on an automatic basis. Simple Leeds and Northrup-computing circuits are being added to the control equipment at each plant, so as to allocate load among the units in the plants in the same manner as the GEDA computer assumes in its calculations. However, system response to regulating demands is independent of the economic allocation and overrides such allocation if necessary. The computer is supervising the control of the system approximately 95 per cent of the time, and in operation has met all expectations as to accuracy and flexibility. Also, use of the computer has eliminated many scheduling chores and has relieved engineering and operating personnel of tedious arithmetic tabulation work which was necessary with the preparation of precalculated dispatches. Operator acceptance has been quite enthusiastic and it is becoming increasingly more difficult to get them to allow the engineers to use it for other purposes.
Quasielastic light scattering by biopolymers. III. Effect of ionic strength on internal dynamics of DNA.

Quasielastic light-scattering data on DNA in 0.1, 0.5, and 1.0M NaCl, neutral pH, have been obtained in the scattering angle range 15 ⩽ θ ⩽ 50. The relaxation curves have been analyzed as a single exponential with a reciprocal relaxation time of the form 2DeffK2, where K is the fluctuation vector [proportional to sin(θ/2)] and Deff is the effective diffusion coefficient. The 1/τ vs sin2(θ/2) curves exhibit two regions that are proportional to sin2(θ/2), in accordance with the Lee-Schurr and Lin-Schurr theories for independent segment-mean force and Rouse-Zimm flexible polymers, respectively. In the region KR 1 represents the diffusion coefficient for a polymer segment. The data reported here indicate that the “transition” region between the two K2 extremes is strongly dependent on the ionic strength of the solvent. This observation, along with the salt variation of the segmental diffusion coefficient, suggests the internal dynamics of DNA are dependent on the ionic strength of the solvent. The relation of the present study to those of Lin and Schurr and of Caloin et al. is discussed.
A Sociodemographic and Partisan Analysis of Voting in Three Anti-Gay Rights Referenda in Oregon*

Since 1988, three separate anti-gay rights referenda have been placed on the ballot in the state of Oregon. While in 1988 Oregon voters passed the first measure (subsequently found unconstitutional), they rejected similar referenda in 1992 and 1994. This paper examines the electoral geography of these three referenda both cartographically and quantitatively. It finds patterns of support for the referenda were closely associated with voting patterns for the Republican Party in gubernatorial and presidential elections, and with sociodemographic indicators reflective of traditionalist areas.
The geology of the Titanic site and vicinity

Abstract The southern approaches to the R.M.S. Titanic site are dominated by Cameron Canyon whose floor is carpeted by sediment debris and slumps, and an area of bottom current bedforms that we have designated the Titanic Sediment Wave Field. This field, characterized by barchan dunes, sand ribbons and sheets, and mud waves owes its origin to the Western Boundary Undercurrent. North of the field is the R.M.S. Titanic site. The hull which is in two parts 600 m apart apparently broke in two at the surface with the stern section sinking directly to the bottom, and the bow following a more gradual descent to its final resting place
Perceptions of social support provided to smokers

Introduction: Cessation efforts and maintained abstinence in smokers have been associated with social support from others (i.e., 'support persons'). Characteristics of support persons appear to affect the amount and quality of support provided to adults who smoke. In the present investigation, the relationship between support person characteristics and perceived quality and quantity of smoking-specific support provided was examined. Method: College students (N = 244) were asked to identify an adult who smokes about whom they were concerned. Participants reported demographic and smoking-related information about themselves and their identified smoker and perceptions of positive and negative smoking-specific social support provided. Results: Results indicated significant differences in smoking status (p < .05), such that current and ex-smokers reported providing more negative support than never smokers. Additionally, participants romantically involved with their smokers reported providing more positive (p < .05) support than those in other relationships. Discussion: Findings suggest the importance of relationship in the perception of support provided during the cessation process and highlight the need for future research in this area.
Syntheses and structures of bis(tricarbonylchromium)-substituted α,ω-diphenylhexatriene complexes

Abstract Treatment of several (4-substituted benzaldehyde)chromium tricarbonyl complexes with bisphosphoranes provides the first examples of (4,4′-substituted α,ω-diphenylhexatriene)bis(chromium tricarbonyl) complexes in good yield. Systems containing both donor and acceptor substituents may be prepared. The structures of three examples, [E,E,E-,η6-4-R-C6H4-(CHCH)3-η6-C6H4-4′-R][Cr(CO)3]2, (R = Me2N, 1; R = Me3Si, 3; R = F3C, 4) have been determined by single crystal X-ray diffraction. The results demonstrate that the olefinic portions of the molecules adopt the all trans E,E,E conformation, and that the tricarbonylchromium groups adopt anti orientations on each face of the organic plane. Compounds 3 and 4 are soluble enough to allow acquisition of 1H NMR spectra of sufficient quality to allow the accurate simulation of the resonances corresponding to the olefinic protons. The simulations suggest that the hexatriene moiety behaves as three independent double bonds, in accord with the structural results.
Recognizing entailment in intelligent tutoring systems

This paper describes a new method for recognizing whether a student's response to an automated tutor's question entails that they understand the concepts being taught. We demonstrate the need for a finer-grained analysis of answers than is supported by current tutoring systems or entailment databases and describe a new representation for reference answers that addresses these issues, breaking them into detailed facets and annotating their entailment relationships to the student's answer more precisely. Human annotation at this detailed level still results in substantial interannotator agreement (86.2%), with a kappa statistic of 0.728. We also present our current efforts to automatically assess student answers, which involves training machine learning classifiers on features extracted from dependency parses of the reference answer and student's response and features derived from domain-independent lexical statistics. Our system's performance, as high as 75.5% accuracy within domain and 68.8% out of domain, is very encouraging and confirms the approach is feasible. Another significant contribution of this work is that it represents a significant step in the direction of providing domain-independent semantic assessment of answers. No prior work in the area of tutoring or educational assessment has attempted to build such domain-independent systems. They have virtually all required hundreds of examples of learner answers for each new question in order to train aspects of their systems or to hand-craft information extraction templates.
University Technology Transfer Through Licensing

SINCE 1980, UNIVERSITIES AND COMPANIES HAVE BEEN WORKING TOGETHER TO TRANSFER TECHNOLOGY FROM THE LAB TO THE MARKETPLACE. HERE'S A GENERAL OVERVIEW AND AN EXAMPLE OF STANFORD UNIVERSITY'S APPROACH.
Detecting flaws in Portland cement concrete using TEM horn antennae

To understand the dielectric properties of PCC and better correlate them with type and severity of PCC internal defects, a study was conducted to evaluate PCC complex permittivity and magnetic permeability over a wideband of frequencies using both time domain and frequency domain techniques. Three measuring devices were designed and fabricated: a parallel plate capacitor, a coaxial transmission line, and transverse electromagnetic (TEM) horn antennae. The TEM horn antenna covers the microwave frequencies. The measurement technique involves a time domain setup that was verified by a frequency domain measurement. Portland cement concrete slabs, 60 by 75 by 14 cm, were cast; defects include delamination, delamination filled with water, segregation, and chloride contamination. In this paper, measurements using the TEM horn antennae and the feasibility of detecting flaws at microwave frequency are presented.
A research agenda for American Jewry

Cet article se penche sur le programme de recherche en sciences sociales concernant la communaute juive americaine dans un contexte ideologique et religieux
Selective Borohydride Reduction Using Functionalized Atomic Force Microscopy Tips

A powder of a selective reducing agent, sodium triacetoxyborohydride (Na(OAc)3BH4), has been attached to an atomic force microscopy tip and used to selectively reduce a monolayer of imines (formed from the reaction of cystamine molecules with cyclopentanone) to their corresponding secondary amines within a well-defined region. Confirmation of the completion of the reaction came through the use of surface mid-IR results as well as with the use of the chloranil test in which the secondary amines were reacted with acetaldehyde to form an enamine that was then conjugated with chloranil to form a localized colored complex, observable by optical means, in a spatially distinct area, traced out by the scanning tip.
Solitons on an axially nonuniform optical fiber

The conditions necessary for the amplitude or the temporal width of an N = 1 soliton to increase, remain constant, or decrease with distance on an axially nonuniform optical fiber are derived. Numerical results for a step-index fiber with an axially tapered core are presented. The effects of such a fiber on higher-order solitons are also presented.
Real-time demand response with uncertain renewable energy in smart grid

We consider a set of users served by a single load-serving entity (LSE) in the electricity grid. The LSE procures capacity a day ahead. When random renewable energy is realized at delivery time, it actively manages user load through real-time demand response and purchases balancing power on the spot market to meet the aggregate demand. Hence, to maximize the social welfare, decisions must be coordinated over two timescales (a day ahead and in real time), in the presence of supply uncertainty, and computed jointly by the LSE and the users since the necessary information is distributed among them. We formulate the problem as a dynamic program. We propose a distributed heuristic algorithm and prove its optimality when the welfare function is quadratic and the LSE's decisions are strictly positive. Otherwise, we bound the gap between the welfare achieved by the heuristic algorithm and the maximum in certain cases. Simulation results suggest that the performance gap is small. As we scale up the size of a renewable generation plant, both its mean production and its variance will likely increase. We characterize the impact of the mean and variance of renewable energy on the maximum welfare. This paper is a continuation of [2], focusing on time-correlated demand.
An exact formula for the maximum VCO sweep rate of a PLL

In many phase-locked loop (PLL) applications, the natural pull-in mechanism is too slow and unreliable, and it must be accelerated. By adding an externally-generated ramp to its control voltage input, the PLL voltage controlled oscillator (VCO) frequency can be swept towards the input reference frequency in an attempt to speed up the pull-in process. This popular acquisition aid has a significant limitation when it is used in a second-order, Type II PLL. If the applied ramp voltage has a slope magnitude greater than (alternatively, less than) some value Rm, the PLL state can (alternatively, cannot) sweep past the desired lock point, resulting in a phase lock failure (alternatively, success). In general, the maximum sweep rate magnitude Rm can be computed by using a numerical integration-and-search procedure that is described in the PLL literature. A special case exists for a second-order, Type II PLL that incorporates a triangular-characteristic phase detector (with logic-level binary input signals). For this case, it is possible to develop an exact, closed-form expression for Rm, the main result of this paper. For a range of loop parameters most often used in applications, Rm values are computed by using the exact formula, and these are used in two ways. First, they are used to validate the previously-mentioned numerical integration-and-search procedure. Second, they are compared to maximum sweep rate values computed for a PLL that utilizes a sinusoidal phase detector to show that the triangular-phase-detector PLL can be swept significantly faster than the sinusoidal-phase-detector loop.
We Finished the Plan, So Now What? Impacts of Collaborative Stakeholder Participation on Land Use Policy

Approaches to environmental policy in the United States and other westernized countries now includes participatory efforts to involve multiple stakeholders in decisions. Rather than calling for a reliance on government officials to solve environmental problems, this approach calls for empowering a community of stakeholders to contribute meaningfully. This article considers the impacts of collaborative stakeholder participation on land use policy. The author undertook a multiple-case analysis of county-level, community-based task forces working on farmland preservation planning in Ohio, U.S. The results show patterns of policymaking processes and the near-term impacts of collaborative planning. The author discusses the results as they link to prior empirical studies, as well as to the Institutional Analysis and Development framework, which integrates physical, social, and institutional variables to examine collective decision-making related to natural resources. The author concludes that the degree of policy change is associated closely with local contextual factors, rather than internal group factors (such as communication, education, debate) often emphasized in studies of citizen advisory committees and collaborative groups. Changing policy outcomes depends not only on providing citizens with resources, but also on situating citizen input within a context that is amenable to policy change.
Probabilistic finite element analysis of a craniofacial finite element model

We employed a probabilistic finite element analysis (FEA) method to determine how variability in material property values affects stress and strain values in a finite model of a Macaca fascicularis cranium. The material behavior of cortical bone varied in three ways: isotropic homogeneous, isotropic non-homogeneous, and orthotropic non-homogeneous. The material behavior of the trabecular bone and teeth was always treated as isotropic and homogeneous. All material property values for the cranium were randomized with a Gaussian distribution with either coefficients of variation (CVs) of 0.2 or with CVs calculated from empirical data. Latin hypercube sampling was used to determine the values of the material properties used in the finite element models. In total, four hundred and twenty six separate deterministic FE simulations were executed. We tested four hypotheses in this study: (1) uncertainty in material property values will have an insignificant effect on high stresses and a significant effect on high strains for homogeneous isotropic models; (2) the effect of variability in material property values on the stress state will increase as non-homogeneity and anisotropy increase; (3) variation in the in vivo shear strain values reported by Strait et al. (2005) and Ross et al. (2011) is not only due to variations in muscle forces and cranial morphology, but also due to variation in material property values; (4) the assumption of a uniform coefficient of variation for the material property values will result in the same trend in how moderate-to-high stresses and moderate-to-high strains vary with respect to the degree of non-homogeneity and anisotropy as the trend found when the coefficients of variation for material property values are calculated from empirical data. Our results supported the first three hypotheses and falsified the fourth. When material properties were varied with a constant CV, as non-homogeneity and anisotropy increased the level of variability in the moderate-to-high strains decreased while the level of variability in the moderate-to-high stresses increased. However, this is not the pattern observed when CVs calculated from empirical data were applied to the material properties where the lowest level of variability in both stresses and strains occurred when the cranium was modeled with a low level of non-homogeneity and anisotropy. Therefore, when constant material property variability is assumed, inaccurate trends in the level of variability present in modest-to-high magnitude stresses and strains are produced. When the cranium is modeled with the highest level of accuracy (high non-homogeneity and anisotropy) and when randomness in the material properties is calculated from empirical data, there is a large level of variability in the significant strains (CV=0.369) and a low level of variability in the modest-to-high magnitude stresses (CV=0.150). This result may have important implications with regard to the mechanical signals driving bone remodeling and adaptation through natural selection.
Effect of Pathological and Physiological Loads on Interleukin-1α Protein Production in Porcine Menisci

The meniscus performs several functions for the maintenance of knee joint health, such as load transmission and joint stability. Meniscal lesions have been suggested as a precursor to the onset of osteoarthritis (OA)[1]. Such lesions often lead to surgical removal of the torn portion of the meniscus, increasing cartilage to cartilage contact area. Partial meniscectomies have been shown using finite element analysis and histology to lead to altered and increased mechanical loading on the remaining meniscus and underlying articular cartilage[2,3]. Consequently, pathological compressive strains of more than 15% have been shown to increase proteoglycan breakdown and meniscal matrix degradation[4]. Preliminary investigations in our laboratory have demonstrated an increase in interleukin-1α (IL-1α) gene expression of meniscal explants subjected to pathological levels of dynamic compressive strain [6,7]. This inflammatory cytokine has been attributed to apoptosis and matrix degradation[5]. However, gene expression measurements merely suggest possible matrix remodeling mechanisms and do not necessarily result in protein syntheses from which matrix changes occur. Therefore, the purpose of this study was to quantify protein synthesis of IL-1α in porcine meniscal implants after compressive strain exercises. It was hypothesized that, similar to mRNA expression, protein synthesis for pathologically loaded (0 or 20% dynamic strain) samples would be greater than samples loaded to physiological levels (10% strain).Copyright © 2008 by ASME
Development of a focusing mirror for SANS

A 2.4 meter long, doubly curved, grazing incidence mirror is being developed for a 30 meter high resolution small angle neutron scattering (SANS) instrument now in operation at NIST's Cold Neutron Research Facility. A focussing mirror can in principle yield a higher flux at the sample for a given angular resolution than the pinhole collimation normally used in SANS instruments, provided that a sufficiently sharp focus can be achieved. The mirror is being constructed from 8, 30 cm long, concave cylindrical quartz segments that have surfaces with a mean roughness, (alpha) s, ranging from 0.3 to 0.9 nm. The mirror segments will be aligned along an arc and bent slightly to approximate an overall toroidal shape. The results of design calculations for the mirror system; of neutron reflectivity measurements of the specular and nonspecular scattering from the individual mirror segments and from test pieces with nickel coatings; and tests of the mirror bender are described. From these results, the overall gain in flux that can be realistically expected from the completed mirror system is estimated.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Molecular beacon-based tricomponent probe for SNP analysis in folded nucleic acids

Hybridization probes are often inefficient in the analysis of single-stranded DNA or RNA that are folded in stable secondary structures. A molecular beacon (MB) probe is a short DNA hairpin with a fluorophore and a quencher attached to opposite sides of the oligonucleotide. The probe is widely used in real-time analysis of specific DNA and RNA sequences. This study demonstrates how a conventional MB probe can be used for the analysis of nucleic acids that form very stable (T(m) > 80 °C) hairpin structures. Here we demonstrate that the MB probe is not efficient in direct analysis of secondary structure-folded analytes, whereas a MB-based tricomponent probe is suitable for these purposes. The tricomponent probe takes advantage of two oligonucleotide adaptor strands f and m. Each adaptor strand contains a fragment complementary to the analyte and a fragment complementary to a MB probe. In the presence of a specific analyte, the two adaptor strands hybridize to the analyte and the MB probe, thus forming a quadripartite complex. DNA strand f binds to the analyte with high affinity and unwinds its secondary structure. Strand m forms a stable complex only with the fully complementary analyte. The MB probe fluorescently reports the formation of the quadripartite associate. It was demonstrated that the DNA analytes folded in hairpin structures with stems containing 5, 6, 7, 8, 9, 11, or 13 base pairs can be detected in real time with the limit of detection (LOD) lying in the nanomolar range. The stability of the stem region in the DNA analyte did not affect the LOD. Analytes containing single base substitutions in the stem or in the loop positions were discriminated from the fully complementary DNA at room temperature. The tricomponent probe promises to simplify nucleic acid analysis at ambient temperatures in such applications as in vivo RNA monitoring, detection of pathogens, and single nucleotide polymorphism (SNP) genotyping by DNA microarrays.
Membership in a research consortium: the project selection game

Abstract Members of research consortia have individual interests that may coincide or conflict with respect to two issues: the projects selected for funding, and the benefits shared among members. We model these firms as players in a cooperative game in coalitional form – the project selection game , and analyze normative decision strategies for firms considering collaborative research. With unlimited budgets for research, cooperation is optimal in the project selection game. With finite budgets, while cooperation is efficient for the consortium as a whole, it may not be optimal for the individual firms. In this case, we examine sufficient conditions for optimal cooperation.
Experimental Characterization and Finite Element Implementation of Soft Tissue Nonlinear Viscoelasticity

Finite element (FE) models of articular joint structures do not typically implement the fully nonlinear viscoelastic behavior of the soft connective tissue components. Instead, contemporary whole joint FE models usually represent the transient soft tissue behavior with significantly simplified formulations that are computationally tractable. The resultant fidelity of these models is greatly compromised with respect to predictions under temporally varying static and dynamic loading regimes. In addition, models based upon experimentally derived nonlinear viscoelastic coefficients that do not account for the transient behavior during the loading event(s) may further reduce the model’s predictive accuracy. The current study provides the derivation and validation of a novel, phenomenological nonlinear viscoelastic formulation (based on the single integral nonlinear superposition formulation) that can be directly inputted into FE algorithms. This formulation and an accompanying experimental characterization technique, which incorporates relaxation manifested during the loading period of stress relaxation experiments, is compared to a previously published characterization method and validated against an independent analytical model. The results demonstrated that the static and dynamic FE approximations are in good agreement with the analytical solution. Additionally, the predictive accuracy of these approximations was observed to be highly dependent upon the experimental characterization technique. It is expected that implementation of the novel, computationally tractable nonlinear viscoelastic formulation and associated experimental characterization technique presented in the current study will greatly improve the predictive accuracy of the individual connective tissue components for whole joint FE simulations subjected to static and dynamic loading regimes.
Long-time scale models of transformers for the determination of transient voltages

The long-time scale model is particularly advantageous for detailed and thorough studies requiring measurements at a large number of points, with a variety of applied waves, winding terminations, and connections. Such studies are indispensable for the correct design of the insulation in modern large high-voltage power transformers. The applications of these models include design and development, improvement of present designs to establish uniform safety factors, investigation and modification of new structures and winding arrangements, and in special cases determination of which structure is best suited to meet customer specifications.
The effect of sustained submaximal clenching on maximum bite force in myofascial pain dysfunction patients.

Summary The effect of a sustained (30% maximum) isometric clenching task on the maximum voluntary bite force level was evaluated on normal jaw function subjects as well as on abnormal jaw function subjects (MPD patients). The results indicate that the MPD subjects had a lower maximum voluntary bite force level and a shorter endurance time when compared to normal subjects. Neither the control subjects nor the MPD subjects demonstrated a change in their brief MVBF after a ‘fatigue inducing’ task. These results suggest a lack of contractile element failure in the jaw closing muscles following sustained submaximal isometric clenching on a force transducer.
The influence of target oxidation and growth-related effects on the electrical properties of reactively sputtered films of tin-doped indium oxide

Abstract The electrical properties of tin-doped indium oxide films prepared by reactive r.f. magnetron sputtering were studied. The properties vary markedly with the added oxygen pressure and also with the film thickness owing to growth effects and target oxidation. The growth effects were analysed in terms of the grain size effects and of the target oxidation by a simple kinetic model. We show that films exhibiting a wide range of electrical properties can be prepared if the deposition conditions are carefully controlled. Films with conductivities as high as 2.5 × 10 3 ohms −1 cm −1 and with optical transmission greater than 85% averaged over the visible spectrum were deposited.
An efficient continuation method for the solution of difficult equilibrium stage separation process problems

Abstract A continuation method is proposed for solving equilibrium stage separation process problems that are extremely difficult to solve using Newton's method The Murphree stage efficiency is used as the continuation parameter. The procedure used to generate initial estimates of the independent variables is c Numerical results show the method to be very effective at converging to the solution of the MESH equations. The method can be implemented very quickly in an existing code that solves the equilibrium stage model equations using Newton's method.
Quiescent affinity inactivators of protein tyrosine phosphatases

alpha-Halobenzylphosphonates were investigated as possible inactivators of protein tyrosine phosphatases (PTPases). These compounds inactivate the Yersinia PTPase (Yop51*delta 162) in a time- and concentration-dependent fashion. This inactivation is active-site directed and irreversible, and is surprisingly rapid in light of the stability of the alpha-halobenzylphosphonates toward nucleophiles in solution. The potential of these molecules for probing the stereochemistry of PTPase inactivation, as well as for providing a useful paradigm for the design of more potent PTPase inhibitors is discussed.
Effects of Bioremediation on Toxicity and Chemical Composition of No. 2 Fuel Oil: Growth Responses of the Brown Alga Fucus vesiculosus

Abstract We conducted a laboratory experiment to assess the effectiveness of nutrient (N and P) application to indigenous, marine microbial populations as a bioremediation technique to respond to oil spills along the temperate coastline of the western North Atlantic. We investigated the effects of various concentrations (10 ppm to 1 ppt) of No. 2 fuel oil, a commonly transported oil, on growth rates of the intertidal macroalga Fucus vesiculosus. We found growth inhibition after a one-day application of the lowest concentration tested and a clear dosage effect. The sensitivity of F. vesiculosus to oiling suggests that this abundant brown alga may serve as an effective indicator species. Nutrient (N + P) application as a bioremediation technique ameliorated the toxic effects of oil on F. vesiculosus without resulting in enrichment of macroalgal growth. Analysis of treatment samples with gas chromatography indicated greater microbial breakdown of the oil under enriched, compared with unenriched conditions. We measured a complete loss of n-alkanes, the preferred substrate by micro-organisms, from `enriched+oiled' samples after 18 days, while oil introduced to autoclaved seawater showed only minimal degradation. Bioremediation may be a viable clean-up alternative for petroleum contamination of temperate ecosystems, particularly in areas of heavy shipping traffic, which probably support a relatively large background population of oil-degrading organisms.
Dynamics of hydrogenic retention in molybdenum: First results from DIONISOS

Abstract The DIONISOS (Dynamics of ION Implantation and Sputtering of Surfaces) experiment is described. DIONISOS features steady-state plasma exposure of material surfaces, with simultaneous, in situ, non-destructive depth profiling on the same surfaces with ion beam analysis (IBA). A steady-state RF helicon plasma source produces a fusion ‘edge-like’ low temperature ( T ∼ 1–10 eV), high-density (⩽10 17–18 m −3 ), steady-state, cylindrical, plasma ( ϕ ∼ 50 mm). The exposure stage allows for the control of sample surface temperature (300–800 K), incident ion energy (10–500 eV), and ion beam and magnetic field incident angle (360° rotation), during bombardment with high plasma flux (∼10 20 –10 22 s −1 m −2 ). First results from DIONISOS show a large and evolving concentration of deuterium (∼1000 appm) trapped deep (∼5 μm) in molybdenum. IBA during plasma exposures shows the surface dynamic deuterium inventory increased by a factor of 2 over the ‘long-term’ trapped inventory at an incident ion flux density of ∼1.5 × 10 21 D/m 2 s.
JOSEPH A. FOLEY (ed.), Language, education and discourse: Functional approaches

Joseph A. Foley (ed.), Language, education and discourse: Functional approaches . London: Continuum, 2004. Pp. xii, 337. Hb. $150.00, Pb. $49.95. Since it was developed by Michael Halliday more than 40 years ago, Systemic Functional Linguistics (SFL) has become increasingly influential in discourse analytic and educational studies. Readers interested in this approach will find illustrations of the theory and its applications in this product of the International Systemic Functional Linguistics Association meeting in 1999 in Singapore. SFL, a theory of language that links meaning with form and describes language in terms of its role in social contexts, offers researchers interested in language in society theoretically grounded ways of focusing on the meaning-making resources of language. These SFL studies, in contexts that span the years of schooling and focus on a range of disciplinary contexts, including mathematics, history, science, and language arts, highlight the power of classroom discourse and the role of language in construing ideologies.
Force field and self‐consistent field calculations on a trans coplanar disulfide: Bis(2‐pyrimidyl)disulfide

Two diaryl disulfides, bis(2-pyrimidyl)disulfide and diphenyldisulfide, have been characterized by molecular mechanics and molecular orbital calculations. When complexed with Cu(I), the pyrimidyl disulfide is known to have a unique 180° CSSC dihedral angle and to be coplanar. Our analysis of the conformational energies of the rotamers suggests that copper–ring interactions are primarily responsible for altering the molecular and electronic structure of the disulfide such that the trans barrier to rotation about the SS bond is effectively overcome. In contrast, the phenyl and uncomplexed pyrimidyl disulfides prefer the usual CSSC torsional angle near 85° and have trans barriers greater than 7 kcal/mol. The barrier to rotation about SC bonds (2–3 kcal/mol) is low and consistent with ab initio calculations and experiments on other molecules. The force field calculations were done using MMP1. A serious problem was encountered in the use of the MMP1 computer program on molecules with N-type atoms that contribute only one electron to the π-electron system. A solution is to modify the variable electronegativity self-consistent field (VESCF) part of the MMP1 calculation to use another set of parameters in the program that pertain to a type of nitrogen with one π electron. CNDO/2 was used for most of the MO calculations, although INDO and extended Huckel were also used.
Designing a 32 element array at 76GHz with a 33dB taylor distribution in waveguide for a radar system

A compact linear pyramidal horn array for a personnel avoidance radar system for robotic vehicles was designed, fabricated and measured. The array will be used as the receive antenna in a system that is presented in a companion paper [2]. The horn array is fed with a waveguide power divider that is designed to produce the required Taylor aperture distribution on the array front. The tapered aperture produces low sidelobes that are needed for low interference in the radar system. The 32-element array with 1.3 λ element size and element spacing in the azimuth direction produces a narrow beam. The beam is scanned using a microwave switch that operates on two 8 stacked arrays for 16 scanning steps covering a scanning range of ± 15 degrees. The scanning arrays act as the receiving antenna, where insertion losses have to be minimized for low noise figures. The low loss is achieved using the waveguide divider. The integration of the array and the power divider in one structure helps in reducing the losses. The transmit antenna is a pyramidal horn of dimensions 2.6 λ × 2.6 λ, which produces the required broadbeam. The transmit and receive antennas' gain satisfy the requirements for the radar link.
The Modernization of Israeli Administration

Israeli political, economic, and social achievements have apparently made Israel a developed nation. Social scientists customarily ignore its geographic setting in the developing world and study the country as a phenomenon of political, social and economic development. One aspect, however, is still problematic and controversial. This is the administrative. Israelis doubt the extent to which their governmental administration is developed, by which they mean the extent to which their administration is staffed by trained officials appointed on grounds of merit. While the forms of a modern government service exist, Israelis are skeptical of their substance, because of what they suspect to be widespread instances of inattention to the rules for appointment and promotion to civil service positions. Social scientists seem to have accepted the conventional wisdom of Israeli public opinion and they, too, have judged the Israeli civil service to be embryonic or stunted in development, largely because of political interference in appointments and advancement to senior positions. It is true that in every country the issue of which governmental offices should be political and which administrative is a problem. But this problem is exacerbated in Israel where, because of party politics, it is, ostensibly, one resolution which exists in law and another in fact.