cssi/SciSciGPT-SciSciNet huggingface dataset:
Fine discrimination in the recognition of individual species of phosphatidyl-myo-inositol mannosides from Mycobacterium tuberculosis by C-type lectin pattern recognition receptors.

The Mycobacterium tuberculosis (M.tb) envelope is highly mannosylated with phosphatidyl-myo-inositol mannosides (PIMs), lipomannan, and mannose-capped lipoarabinomannan (ManLAM). Little is known regarding the interaction between specific PIM types and host cell C-type lectin pattern recognition receptors. The macrophage mannose receptor (MR) and dendritic cell-specific ICAM-3-grabbing nonintegrin on dendritic cells engage ManLAM mannose caps and regulate several host responses. In this study, we analyzed the association of purified PIM families (f, separated by carbohydrate number) and individual PIM species (further separated by fatty acid number) from M.tb H37Rv with human monocyte-derived macrophages (MDMs) and lectin-expressing cell lines using an established bead model. Higher-order PIMs preferentially associated with the MR as demonstrated by their reduced association with MDMs upon MR blockade and increased binding to COS-1-MR. In contrast, the lower-order PIM2f associated poorly with MDMs and did not bind to COS-1-MR. Triacylated PIM species were recognized by MDM lectins better than tetra-acylated species and the degree of acylation influenced higher-order PIM association with the MR. Moreover, only higher-order PIMs that bind the MR showed a significant increase in phagosome-lysosome fusion upon MR blockade. In contrast with the MR, the PIM2f and lipomannan were recognized by DC-SIGN comparable to higher-order PIMs and ManLAM, and the association was independent of their degree of acylation. Thus, recognition of M.tb PIMs by host cell C-type lectins is dependent on both the nature of the terminal carbohydrates and degree of acylation. Subtle structural differences among the PIMs impact host cell recognition and response and are predicted to influence the intracellular fate of M.tb.
Carbon dot reduced bimetallic nanoparticles: size and surface plasmon resonance tunability for enhanced catalytic applications

We report on a simple and green route toward monometallic (Au or Ag) and alloyed bimetallic AuAg nanoparticles using citric acid-derived carbon nanodots (C-dots) as the reducing and stabilizing agent. Simple variation in the initial C-dot:metal ratio yields a smoothly tunable surface plasmon resonance and the resulting nanomaterials show excellent catalytic activity for 4-nitrophenol reduction which is fully preserved following 5 months of storage. The Au@C-dot catalyst further demonstrated intrinsic peroxidase activity.
Effect of Different Seawaters on the Development of Biochemically Deficient Mutants of Serratia marinorubra

The effect of different seawaters on survival and growth of biotin-, isoleucine-, and uracil-requiring mutants of the marine bacterium, Serratia marinorubra, has been investigated. Samples of seawater were collected from coastal waters, the California Current, and central North Pacific waters at depths of 1, 25, 50, 100, 250, and 500 m. The growth or survival of the test bacterium in basal medium prepared in these seawater samples was determined. The control water was synthetic or charcoal-treated natural seawater. In several experiments, the metabolite required by the bacterium was added to the basal medium 24 hr after inoculation, and the growth response was determined. Depending on the source, the seawater samples were both stimulating and inhibitory. Surface waters were more inhibitory than those taken at depth, where, in some cases, bacterial growth occurred. Seawater inhibition was related more to station depth than to the location of the station. The most toxic effects were found against the uracil-requiring mutant; the least, against the isoleucine-requiring mutant. The results of these studies and some laboratory experiments indicate that seawater toxicity is not primarily associated with the physical and biological properties of a particular water mass and that the same factor(s) may be responsible for the rapid death of bacteria in all waters.
The Platelet Receptor GPVI Mediates Both Adhesion and Signaling Responses to Collagen in a Receptor Density-dependent Fashion

The platelet response to collagen is a primary event in hemostasis and thrombosis, but the precise roles of the numerous identified platelet collagen receptors remain incompletely defined. Attention has recently focused on glycoprotein VI (GPVI), a receptor that is expressed on platelets in association with a signaling adapter, the Fc receptor gamma chain (Fc Rgamma). Genetic and pharmacologic loss of GPVI function results in loss of collagen signaling in platelets, but studies to date have failed to demonstrate that GPVI-Fc Rgamma expression is sufficient to confer collagen signaling responses. These results have led to the hypothesis that collagen responses mediated by GPVI-Fc Rgamma may require the collagen-binding integrin alpha2beta1 as a co-receptor, but this model has not been supported by a recent study of mouse platelets lacking alpha2beta1. In the present study we have used a novel anti-GPVI monoclonal antibody to measure the level of GPVI on human platelets and to guide the development of GPVI-expressing cell lines to assess the role of GPVI in mediating platelet collagen responses. GPVI receptor density on human platelets appears tightly regulated, is independent from the level of alpha2beta1 expression, and significantly exceeds that on previously characterized GPVI-expressing RBL-2H3 cells. Using newly generated GPVI-expressing RBL-2H3 cells with receptor densities equivalent to that on human platelets, we demonstrate that GPVI expression confers both adhesive and signaling responses to collagen in a graded fashion that is proportional to the GPVI receptor density. These results resolve some of the conflicting data regarding GPVI-collagen interactions and demonstrate that 1) GPVI-Fc Rgamma expression is sufficient to confer both adhesion and signaling responses to collagen, and 2) GPVI-mediated collagen responses are receptor density-dependent at the receptor levels expressed on human platelets.
An integrated approach to liability.

For two decades the increase in proportion of monetary allocation to health services has exceeded the rise in the gross national product. Hospital costs have accelerated out of proportion to other health care costs. For hospitals to operate with effectiveness and efficiency, a maximum effort needs to be given to overcoming the new administrative difficulties and challenges of today’s health care industry. For effective utilization of human resources, hospital administrators should devise a system that would meld preexisting functions that focus on review of specific aspects of care into an organized facility-wide program. The purpose of such a system would be to describe and monitor those areas of accountability, liability, and quality of care. In most hospitals today there are three specific departments, quality assurance (QA), infection control (IC), and risk management (RM), that have similar goals and purposes. If these three areas conduct their activities independently and their information is not integrated, the results are fragmentation, duplication of efforts, and excessive costs. Each department provides and uses similar information and each should be feeding into and drawing from a central data base. The activities of an integrated trio should provide a central data base from which potential problems and/or problematic patterns and trends in patient care and facility management can be identified. Within the triad, the lines of authority and accountability should be clearly defined so that appropriate and timely actions can be taken to resolve problems. The benefits of such an integrated trio
Left ventricular unloading alters receptor tyrosine kinase expression in the failing human heart.

Abstract Background: Experimental and clinical data suggest that the loss of membrane receptor tyrosine kinase (RTK) activity in cardiac myocytes results in increased frequency of apoptotic cell death and progression of heart failure. The goal of our study was to examine the expression characteristics of RTKs in ventricular myocardium obtained from patients before and after mechanical unloading. Methods: We extracted RNA from paired formalin-fixed, paraffin-embedded left ventricular tissue blocks obtained at the time of left ventricular assist device (LVAD) implantation and explantation from a cohort of 36 patients (median age 51 years). The duration of LVAD support ranged from 1 to 314 days (median 95 days), 17 patients had ischemic and 19 non-ischemic cardiomyopathy at the time of LVAD implantation. Using real-time reverse transcription–polymerase chain reaction (RT-PCR) we quantitated transcripts for atrial natriuretic factor (ANF) and tumor necrosis factor-alpha (TNF-α), markers of heart failure, and the RTKs Her2/neu, Her4 and gp130, regulators of cardiac cell survival. Results: In patients undergoing mechanical unloading, ANF and TNF-α mRNA levels were independently suppressed. Her2/neu, along with Her4 was upregulated, mostly in cases of ischemic cardiomyopathy, whereas gp130 levels decreased. Post-LVAD transcript levels of Her2 correlated tightly with gp130 in patients with non-pathologic entry values of gp130. Duration of treatment and age were also determining factors in the change of expression of these genes. Conclusion: Real-time quantitative (Q)-RT-PCR can be used to quantitate gene expression in archival myocardial tissue blocks. Mechanical unloading leads to a re-adjustment of RTK transcript levels, but not their reverting to control values in heart failure patients.
Site-directed substitution of Ser1406 of hamster CAD with glutamic acid alters allosteric regulation of carbamyl phosphate synthetase II.

Ser1406 of the allosteric region of the hamster CAD enzyme, carbamyl phosphate synthetase II (CPSase), is known to be phosphorylatedin vitro by cAMP-dependent protein kinase (PKA). Metabolic labeling experiments described here demonstrate that CAD is phosphorylated in somatic cells in culture. Phosphorylation is stimulated by treating cells with 8-bromo-cAMP, a PKA activator. The stimulation is essentially prevented by pretreatment with H-89, a PKA specific inhibitor. Substitution of Ser1406 with alanine results in an enzyme with kinetics and allosteric regulation indistinguishable from unsubstituted CAD. However, substitution to glutamic acid increases CPSase activity by reducing the apparent Km (ATP). The UTP concentration required to give 50% inhibition is increased rendering this altered enzyme significantly less sensitive to feedback inhibition, but allosteric activation by PRPP is unaffected. While these data do not prove that Ser1406 is phosphorylatedin vivo, they do indicate that a specific alteration at this residue can affect allosteric regulation.
The emporium approach to computer science education

As an alternative to laboratories for computer science programming courses, the Emporium style of learning environment has advantages for a course concerned with the foundations and principles of computer science. Following the lead from courses in freshman mathematics, this paper describes the active learning and assessment methodologies incorporated into a freshman computer science course. The results have been encouraging, and student acceptance of an alternative approach to learning is improving.
Fabrication of high aspect-ratio polymer microstructures for large-area electronic portal x-ray imagers

Megavoltage x-ray imaging performed during radiotherapy is the method of choice for geometric verification of patient localization and dose delivery. Presently, such imaging is increasingly performed using electronic portal imaging devices (EPIDs) based on indirect detection active matrix flat panel imagers (AMFPIs). These devices use a scintillating phosphor screen in order to convert incident x-rays into optical photons, which are then detected by the underlying active matrix photodiode array. The use of a continuous phosphor introduces a trade-off between x-ray quantum efficiency and spatial resolution, which limits current devices to use only ∼2% of the incident x-rays. This trade-off can be circumvented by "segmented phosphor screens", comprising a two-dimensional matrix of optically-isolated cell structures filled with scintillating phosphor. In this work we describe the fabrication of millimeter-thick segmented phosphor screens using the MEMS (micro-electro-mechanical-system) polymer SU-8. This method is capable of being extended to large-area substrates.
Multimodal Literacy and Theater Education.

In this article, the author explores the possibilities of teaching and learning through multiple-literacies in an arts environment. Acknowledging that technologies have a profound effect on our society, and often outpace our ability to properly assess or understand their implications, the author asserts that young people can become critical and active agents in their interactions with new media. Arts education, specifically theater education, is uniquely positioned to substantially contribute to these interactions between teachers and students that acknowledge and explore the new forms of literacy that are essential to navigating our contemporary culture. To this end, the author calls on arts educators to effectively engage with their students' multimodal concerns through interactions that value new multimodal literacies.
Flame structure study of a lean H2/N2O/Ar Flame employing molecular beam mass spectrometry and modeling

Abstract A combined experimental and detailed modeling study has been performed on a fuel-lean (Φ = 0.64), 20-torr, low-pressure, burner-stabilized H2/N2O/Ar flame. Species concentration and temperature profiles were obtained using molecular beam mass spectrometry and thin-wire Pt PtRh(10%) thermocouples, respectively. Species profiles include H2, N2O, N2, H2O, NO, O2, H, O, and OH. These profiles are compared with calculated profiles generated using PREMIX, a one-dimensional premixed laminar flame code. The detailed chemical mechanism employed in the code consists of 38 reactions and 14 species, and was derived from preliminary calculations using a more comprehensive set of reactions (> 200) obtained from a critical literature review. Rate and sensitivity analyses were performed on the PREMIX results using an interactive postprocessing code we have written so that the details of the chemistry may be understood. The results provide a stringent test of the detailed chemical flame model and chemical mechanism for the H2/N2O/Ar system.
Sustained ventricular fibrillation in a conscious patient.

A 44-YEAR-OLD MAN WITH A NONISCHEMIC DIlated cardiomyopathy treated with an implanted left ventricular assistdevice (LVAD) was admitted to our hospital for diuresis after presenting with acute decompensated heart failure. His admission blood pressure was 95/65 mm Hg. Serial troponin measurements were negative. While hospitalized, the patient developed a wide complex tachycardia on telemetry monitoring resulting in multiple successive discharges from his implantable cardioverterdefibrillator (ICD). On evaluation, the patient was conversant and without complaint of lightheadedness or palpitations. Bilateral radial and femoral pulses were absent. An automated cuff was unable to measure a brachial blood pressure in either arm. An electrocardiogram (ECG) was obtained (Figure 1). Question: How can the patient’s ECG be reconciled with his clinical appearance and physical findings?
Variation of Hardness and Modulus across the Thickness of Zr-Cu-Al Metallic Glass Ribbons

We investigate through-thickness hardness and modulus of Zr50Cu45Al5 metallic glass melt-spun ribbon. Because of their thinness, the ribbons are challenging to measure, so we employ a novel nanoindentation based-method to remove artifacts caused by ribbon flexing and edge effects. Hardness and modulus vary approximately linearly across the thickness but, unlike bulk ingots, the side of the ribbon that cooled most quickly had the highest hardness and modulus. This “inverse” variation may be caused by the fast-moving solidification front, which might conceivably, for instance, push free volume in advance of it. Annealing near T g causes both hardness and modulus to increase and become more uniform across the thickness.
The radiation pattern of a truncated Gaussian aperture distribution

The optical configuration allowing most efficient transmission of laser beams over long distances has been determined from the computer calculations described, which give the radiation pattern and received intensity of arbitrarily truncated Gaussian aperture distributions. Some representative radiation patterns and received intensity vs. beam truncation are plotted.
An overview of anthrax infection including the recently identified form of disease in injection drug users.

Purpose Bacillus anthracis infection (anthrax) can be highly lethal. Two recent outbreaks related to contaminated mail in the USA and heroin in the UK and Europe and its potential as a bioterrorist weapon have greatly increased concerns over anthrax in the developed world.
Sound Propagation Near the Magnetic Phase Transition in EuO

In EuO we observe no critical attenuation of sound near ${T}_{c}$, but a corresponding critical change in sound velocity is noticeable. These experiments can be explained by the experimentally verified fact that the sound wave couples to the energy of the spin system.
The Babuška-Brezzi condition and the patch test: an example

Abstract This paper discusses an example of a mixed finite element method in one dimension which satisfies the engineering patch test, but does not satisfy a uniform inf-sup condition. The inf-sup constant for this method is shown to be of order h2. The reasons for good results from benchmark problems for this method are addressed by characterizing the nature of input data for which the method performs well. Numerical results illustrating the effect of the non-uniform inf-sup condition are presented.
A Few Recent Experiments on Surface Studies by Second Harmonic Generation

Surface second harmonic generation (SHG) has recently been shown to be a viable tool for surface studies.1 It is sensitive to submonolayers of molecules on surfaces and has many obvious advantages in comparison with the conventional surface tools. Being optical, it is nondestructive, capable of in-situ remote sensing, and applicable to any interface assessible by light. The time response of SHG is nearly instantaneous. Therefore, the technique also has the potential of being useful for surface dynamic studies with extremely high time resolution. Thus, surface SHG can provide many unique opportunities in surface science research. In the past several years, we have already succeeded in demonstrating that the technique can be used to monitor molecular adsorption and desorption at a variety of interfaces,2 to probe the spectrum of submonolayers of molecules adsorbed on surfaces,3 to measure the orientation and distribution of adsorbed molecules,3,4 to study surface reconstruction and phase transformation of semiconductors,5 and so on. In this paper, we describe a few additional experiments that we have recently carried out in our laboratory to further explore the applicability of surface SHG.
Beta and gamma spectroscopic studies of 9.7 d 125Sn

The energy levels in 125Sb populated in the decay of 9.7 d 125Sn have been studied using β- and γ-ray spectroscopy techniques. Singles and coincidence γ-ray spectra were recorded using both NaI(Tl) and Ge(Li) detectors. The high resolution of the Ge(Li) detectors has been used to identify 24 gamma-ray transitions in this decay and coincidence studies suggest the presence of three other weak or unresolved transitions. The observed transitions and coincidence relations have led to the assignment of excited states in 125Sb at 1017.2, 1066.9, 1089.0, 1350.3, 1419.8, 1806.9, 1890.6, 1982.0, 2002.0, 2199.7, 2240.0, 2276.0 and 2288.0 keV. Angular correlation measurements of some of the prominent γ-γ cascades were made and the results used in conjunction with log ft values to limit the possible spin assignments for several of the states.
Quantum kinetic equation in phase-space textured multiband systems

Starting from the density-matrix equation of motion, we derive a semiclassical kinetic equation for a general two-band electronic Hamiltonian, systematically including quantum-mechanical corrections up to second order in space-time gradients. We find, in addition to band-projected corrections to the single-particle equation of motion due to phase-space Berry curvature, interband terms that we attribute to the nonorthorgonality of the projected Hilbert spaces. As examples, we apply our kinetic equation to electronic systems in the presence of spatially inhomogeneous and dynamical spin textures stemming from electromagnetic gauge potentials, and specifically to the electromagnetic response of massive 2D Dirac fermions and 3D Weyl fermions.
Effects of Foliar Nutrient Application on Highbush Blueberries

Abstract The influence of foliar applied urea and KNO3 on shoot N status was determined, along with the absorption of foliar applied NO3-N by leaf tissue and it's subsequent translocation to other parts of the plant. The effect of foliar N applications on berry yield, quality, and leaf N levels was also measured in the field. None of the foliar applications had a significant effect on plant N status or yield. The N derived from the foliar sprays comprised only a small percentage of the total N in leaves, and leaves contained more foliar derived N than shoots. Plants did absorb more N from urea than KNO3 applications.
Mortality after acute renal failure: Models for prognostic stratification and risk adjustment

To adjust adequately for comorbidity and severity of illness in quality improvement efforts and prospective clinical trials, predictors of death after acute renal failure (ARF) must be accurately identified. Most epidemiological studies of ARF in the critically ill have been based at single centers, or have examined exposures at single time points using discrete outcomes (e.g., in-hospital mortality). We analyzed data from the Program to Improve Care in Acute Renal Disease (PICARD), a multi-center observational study of ARF. We determined correlates of mortality in 618 patients with ARF in intensive care units using three distinct analytic approaches. The predictive power of models using information obtained on the day of ARF diagnosis was extremely low. At the time of consultation, advanced age, oliguria, hepatic failure, respiratory failure, sepsis, and thrombocytopenia were associated with mortality. Upon initiation of dialysis for ARF, advanced age, hepatic failure, respiratory failure, sepsis, and thrombocytopenia were associated with mortality; higher blood urea nitrogen and lower serum creatinine were also associated with mortality in logistic regression models. Models incorporating time-varying covariates enhanced predictive power by reducing misclassification and incorporating day-to-day changes in extra-renal organ system failure and the provision of dialysis during the course of ARF. Using data from the PICARD multi-center cohort study of ARF in critically ill patients, we developed several predictive models for prognostic stratification and risk-adjustment. By incorporating exposures over time, the discriminatory power of predictive models in ARF can be significantly improved.
DAGGERS, RIFLES AND DYNAMITE: ANARCHIST TERRORISM IN NINETEENTH CENTURY EUROPE

Initially the anarchists did not call for terrorism, but by the 1880s, it erupted as the result of harsh socio-economic conditions in Europe and America, regional and national traditions of social warfare and justified regicide, government repression of more peaceful and organized forms of protest and labor activity, the spellbinding examples of the Paris Commune and the assassination of Tsar Alexander II, the invention of dynamite and anarchist incitement to ‘propaganda by the deed’. These ignited chain reactions of social protest, repression and revenge. While the number of assassinated heads of state and government, and of monarchs of major countries was unprecedented, the anarchists, outside of Spain, killed relatively few people. Nonetheless, the anarchists’ desire for dramatic signs of vindication, the authorities’ and the public's fears of a vast anarchist conspiracy and the media's hunger for sensational news combined to create the mirage of a powerful terrorist movement sweeping through nations a...
A Study of the Mechanism and Kinetics of Cyclooctene Epoxidation Catalyzed by Iron(III) Tetrakispentafluorophenyl Porphyrin

A study has been conducted of the mechanism and kinetics of cyclooctene epoxidation by hydrogen peroxide catalyzed by iron(III) tetrakispentafluorophenyl [F20TPPFe(III)] porphyrin. The formation of cyclooctene oxide, the only product, was determined by gas chromatography, and the consumption of hydrogen peroxide was determined by 1H NMR. UV−visible spectroscopy was used to identify the state of the porphyrin as a function of solvent composition and reaction conditions and to follow the kinetics of porphyrin degradation. F20TPPFe(III) was found to be inactive in the chloride-ligated form, but became active when the chloride ligand was replaced by a methoxide ligand. The methoxide-ligated form of F20TPPFe(III) reacts with hydrogen peroxide to form an iron(III) hydroperoxide species, which then undergoes both heterolytic and homolytic cleavage to form iron(IV) π-radical cations and iron(IV) oxo species, respectively. The iron(IV) π-radical cations are responsible for the epoxidation of cyclooctene, whereas t...
Synthesis and characterization of cobalt/gold bimetallic nanoparticles

Cobalt/gold (Co/Au) bimetallic nanoparticles are prepared by chemically reducing gold (III) chloride to gold in the presence of pre-synthesized Co nanoparticles. Transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) absorption spectrometry, and a superconducting quantum interference device (SQUID) magnetometer have been used to characterize as-prepared bimetallic nanoparticles. Our findings demonstrate Au not only grows onto Co nanoparticles, forming a surface coating, but also diffuses into Co nanoparticles. The introduction of Au alters the crystalline structure of Co nanoparticles and changes their magnetic properties. Dodecanethiols induce a reorganization of as-prepared Co/Au bimetallic nanoparticles.
In situ PCR for in vivo detection of foreign genes transferred into rat brain

Abstract Here we describe the use of in situ PCR to detect a viral transgene in rat brain. Previously, we have reported in vivo gene transfer by using a defective herpes simplex viral vector in mammalian brain (Kaplitt, M.G., Pfaus, J.G., Kleopoulos, S.P., Hanlon, B.A., Rabkin, S.D., Pfaff, D.W., Mol. Cell. Neurosci. 2 (1991) 320–330). For detection of the LacZ transgene, we have used histochemical staining for the protein product, β -galactosidase, and in situ hybridization for its mRNA, but the DNA itself cannot be reliably detected with conventional methods. Therefore we have adapted the technique of in situ PCR, so that we may detect minute quantities of transgenic vector DNA following in vivo gene. The brain sections, prefixed, were treated with PBS-detergent before PCR amplification to increase permeability for peptides and oligonucleotides across cellular barriers in brain tissue. Pretreatment with detergent retained better brain morphology than the more widely used proteinase treatment. The PCR mixture containing dNTPs, primers, digoxigenin-dUTP (Dig-dUTP) and buffer was loaded onto each brain section. Slides containing brain sections were placed in an aluminum boat and then on the block of the thermal cycler. Temperature was brought to 82°C before adding Taq polymerase (`hot start' method). Dig-labeled PCR amplified fragments were then detected by alkaline-phosphatase-linked anti-digoxigenin-antibody. Positive signals were seen within the nucleus of transduced neurons, indicating presence of viral DNA. Enhanced specificity was observed with the use of Dig-labeled primers which eliminates the possibility of non-specific viral DNA detection through primer-independent reactions. Overall, this technique can serve not only as an internal control for transgene presence during comparisons of experimental groups of animals, but may also have clinical applications including the detection of viral infection in human brain such as HIV in pathology specimens.
An investigation of instability of phase morphology of blends of nylons with polyethylenes and polystyrenes and effects of compatibilizing agents

Investigations of instability of phase morphology of blends of nylons with polyethylenes and polystyrenes and the effects of “compatibilizing” additives or “agents” are described. Annealing coarsens the phase morphology of blends of nylons with polyethylenes and polystyrenes. Phase growth is observed for various periods of annealing time. The addition of compatibilizing agents, specifically maleic anhydride grafted polyolefins to polyethylene-nylon blends and syrene-maleic anhydride copolymers to polystyrene-nylon blends, stabilize the phase dimensions. Styene-maleic anhydride copolymer is found more effective than styrene acrylonitrile copolymer as a compatibilizing agent. The mechanisms of this behavior are critically discussed.
Effect of Attitude Toward Experiment Participation Upon Performance in a Sensory Deprivation Experiment.

(1969). Effect of Attitude toward Experiment Participation upon Performance in a Sensory Deprivation Experiment. The Journal of General Psychology: Vol. 81, No. 2, pp. 283-286.
Vicher: A virtual reality based educational module for chemical reaction engineering

Virtual reality has the potential to be a powerful new tool in engineering education by bringing experience-based learning to all students, addressing the needs of students with alternate learning styles, and providing enhanced impact to educational presentations. As with any new tool, we must first learn how, when, and where to apply it before it becomes useful. This article describes Vicher, the first known application of virtual reality to chemical engineering education, and some of what has been discovered about virtual reality as an educational tool during Vicher's development. Vicher currently consists of two programs-Vicher I and Vicher II-which deal with the topics of catalyst deactivation and nonisothermal effects in chemical reaction engineering, respectively. Between the two programs, Vicher currently simulates five different engineering areas plus support facilities. Future plans include extensive student testing, program expansion and refinement, and the development of additional virtual reality based educational modules. © 1996 John Wiley & Sons, Inc.
A simple matrix analysis of associative structure

Summary The present paper suggests that interword associative relations among a group of words may be described in terms of an n × n matrix called a W matrix in which the same n words appear as both row and column headings. When any word heads a row it is considered as a stimulus. When it heads a column it is considered as a response. A 1 is entered in the appropriate cell of the W matrix for every column word produced as an associate by a row word. After all associative relations in a set of words have been recorded, the sum of any column of the W matrix, Σ i w i ., denotes the total number of stimulus words producing the j th word as an associate. W matrices, involving words contained in the associative hierarchies produced by 6 different stimulus words, were established in this way. Σ w i . values derived from these W matrices were then shown to predict the relative position of individual words in the associative hierarchies evoked by each of the 6 stimulus words. The results were interpreted to mean that the position of an individual word in an associative hierarchy depends upon the number of other hierarchy words producing that word as an associative response.
Using Pre and Post Low-p Latency to Assess Behavioral Momentum: A Preliminary Investigation

Delivering high-probability (high-p) request sequences is an effective method to increase compliance across settings. To date, researchers have used frequency of compliance and latency to initiate low-probability (low-p) requests to document these effects. Both measures focus on events just prior to and during the low-p task. In these two studies we examined a third possible example of high-p effects, time from the end of a low-p task to the initiation of subsequent high-p tasks, across both traditional high-p and high-p with added incentives conditions. Overall, we found that the latency from high-p to low-p tasks was shorter than the latency from low-p to subsequent high-p tasks, indicating a momentum effect across four children (two with academic difficulties and two without). The results are explained in terms of behavioral momentum and local reinforcement rates.
A Physiologic-Based Approach to the Treatment of a Patient With Hypokalemia

Hypokalemia is common and can be associated with serious adverse consequences, including paralysis, ileus, cardiac arrhythmias, and death. As a result, the body maintains serum potassium concentration within very narrow limits by tightly regulated feedback and feed-forward systems. Whereas the consequences of symptomatic hypokalemia and severe potassium depletion are well appreciated, chronic mild hypokalemia can accelerate the progression of chronic kidney disease, exacerbate systemic hypertension, and increase mortality. Persistent hypokalemia may reflect total-body potassium depletion or increased renal potassium clearance. In a patient with simple potassium depletion, potassium replacement therapy should correct serum potassium concentration, but may have little effect when renal potassium clearance is abnormally increased from potassium wasting. In such cases, the addition of potassium-sparing diuretics might be helpful. Serum potassium concentration is an inaccurate marker of total-body potassium deficit. Mild hypokalemia may be associated with significant total-body potassium deficits and conversely, total-body potassium stores can be normal in patients with hypokalemia due to redistribution. The speed and extent of potassium replacement should be dictated by the clinical picture and guided by frequent reassessment of serum potassium concentration . The goals of therapy should be to correct a potassium deficit, if present, without provoking hyperkalemia. Oral replacement is preferred except when there is no functioning bowel or in the setting of electrocardiogram changes, neurologic symptoms, cardiac ischemia, or digitalis therapy.
Laser heating for chemical conversions: Unique features and limitations

Abstract The wide variety of experiments wherein IR laser radiation was used to initiate or augment chemical conversions may be catalogued by designating the components of a sequence of dichotomies to which they may be assigned. Recent reports in several categories are briefly reviewed. A more extended discussion is presented of those experiments wherein meaningful temperatures may be assigned, even though the systems may not be in complete statistical equilibrium. The latter part of the review is devoted to reports on the application of laser thermolysis for medical and industrial uses.
Flow cytometric analysis of electronic nuclear volume and DNA content in normal mouse tissues.

Light scatter is used in flow cytometry for identification of cells based on their size and/or granularity. However, forward light scatter is not an accurate measure of cell size. The measurement of Electronic Volume (EV) by Coulter principle is more accurate. However, EV cannot be measured on most of the commercially available flow cytometers. We have described the development and applications of a flow cytometer that can simultaneously measure Electronic Nuclear Volume (ENV) and DNA content. In the present study we have used a commercially available NPE QuantaTm for measuring EV and DNA content of different normal mice tissues.Fresh/frozen or formalin fixed-paraffin embedded tissues from mice were processed for isolation of nuclei, which were then analyzed for EV versus DNA content. By using these two parameters, distinct sub-populations were identified in liver, thymus, small intestine and bone marrow. Dual parametric analysis of EV versus DNA content can be a valuable technique for identification of s...
The visualization of concanavalin-A binding sites in the interperiod line of rat sciatic nerve myelin.

— The plant lectin, Concanavalin A (Con A), is used in combination with a peroxidase-labelling technique to visualize carbohydrates in myelin. The major myelin glycoprotein seen by polyacrylamide electophoresis binds Con A. Thin slices of sciatic nerve bind Con A in the interperiod line of the myelin. These data suggest that the glycoprotein may be located at the interperiod line.
Management of Osteopenia of Liver Disease with Special Emphasis on Primary Biliary Cirrhosis

Bone disease occurring in the setting of chronic liver disease is being recognized increasingly often. The osteopenia may be an important cause of morbidity in these patients, particularly as effective treatments become available for the liver diseases and especially if these treatments actually worsen the coexistent bone disease. Although no specific treatments are of proven benefit for the bone disease in most instances, adequate exercise and calcium intake as well as vitamin D supplementation when deficiencies are present are recommended for all patients. Information is lacking about specific treatment for patients with PSC, hemochromatosis, and alcoholic liver disease. For patients with PBC, other than the above general measures, preliminary information suggests that supplemental estrogens in postmenopausal women and the use of calcitonin may offer promise; both measures are deserving of further study in this group of patients.
Action of harman (1-methyl-β-carboline) on the brain: Body temperature and in vivo efflux of 5-HT from hippocampus of the rat

Abstract Harman (1-methyl-β-carboline) has been shown previously to act on the hippocampus of the rat in terms of its evocation of anxiogenic responses and induction of alcohol preference. In the present experiments, the localized perfusion of 200 μM barman in the dorsal hippocampus of freely moving rats increased the levels of serotonin (5-HT) but not 5-hydroxyindoleacetic acid (5-HIAA) in cerebral dialysates. The systemic administration of 5.0–20 mg/kg harman also enhanced 5-HT in the perfusates but reduced the levels of 5-HIAA in a dose-dependent manner, probably as a result of the inhibition of the enzyme monoamine oxidase type A (MAO-A). Harman given systemically in doses of 2.5–20 mg/kg induced an intense hypothermia, with a maximum fall produced by the 5.0 mg/kg dose. This fall in body temperature (Tb) induced by 5.0 mg/kg harman was not antagonized by 5.0 mg/kg of (±)-pindolol. Further, pretreatment of the rats with para-chlorophenylalanine (pCPA) also failed to alter the harman-induced hypothermia. The systemic administration of 10 mg/kg of the MAO-A inhibitor, clorgyline, also lowered Tb significantly. Overall, the present experiments show that harman apparently influences 5-HT systems in the brain by its action in inhibiting MAO-A. This property is likely responsible also for the harman-induced increase of 5-HT in the hippocampus of the rats.
Circular bar construction

Let A be a CDG (commutative differential graded) algebra over a field of characteristic 0, and B(A), the bar construction of A. If C is a DG (differential graded) A @ Amodule, define B(A; C) = C BAOR B(A). If C’ and C” are DG A-modules, then B(A; C’ @ C”) coincides with the usual two sided bar construction B(C’, A, C”). (See [12].) In this sense, B(A; C) closes the two sides of the bar construction and is therefore “circular”. The geometric significance of B(A; C) lies in the case where A = A(M) and C = A(N) are the Rham complexes and the A @ A-module structure of C is induced by a differentiable map f : N-t M x M. Theorem 0.1[6] (Theorem 4.3.1[5]) asserts that, if M and N are differentiable manifolds and if M is simply connected with finite Betti numbers, then H(B(A; C)) is the real cohomology of the pullback space Ef of the following pullback diagram of the free path fibration of M:
Role of formaldehyde hydrazone and catalase in hydrazine-induced methylation of DNA guanine

Hydrazine is acutely neurotoxic, hepatotoxic and nephrotoxic; it is also carcinogenic to liver and lung in rodents. Administration of hydrazine results in formation of 7-methylguanine and O6-methylguanine in target organ DNA of rats, mice, hamsters and guinea-pigs. It has been suggested that hydrazine reacts with endogenous formaldehyde to form a condensation product which could be metabolized to a methylating agent. Solutions of 0.50 mM hydrazine and formaldehyde have, upon mixing, NMR spectra (300 MHz) consistent with the formation of formaldehyde hydrazone but not other possible condensation products such as tetraformyltriazine or formaldehyde azine. These same solutions evidencing hydrazone formation, when incubated in an in vitro system containing post-mitochondrial (S9), microsomal, cytosolic or mitochondrial cell fractions, resulted in the methylation of DNA guanine; S9 was the most active fraction. Neither the P-450 monooxygenase nor flavin monooxygenase systems appeared to be important in hydrazine/formaldehyde-induced methylation of DNA. However, sodium azide, cyanamide and carbon monoxide all inhibited S9-supported DNA methylation. Bovine liver catalase, a heme-containing cytochrome, readily transformed hydrazine/formaldehyde to a methylating agent. The data support formation of formaldehyde hydrazone as the condensation product of hydrazine and formaldehyde which is rapidly transformed in various liver cell fractions, perhaps by catalase and/or catalase-like enzymes, to a methylating agent.
Nanocrystalline non-alkali glass-ceramics

Copyright (c) 1997 Elsevier Science B.V. All rights reserved. Nanocrystalline glass-ceramics with high elastic modulus and moderate strength and toughness can be produced from a wide area in the SiO 2 -Al 2 O 3 -MgO-ZnO-TiO 2 system. Phase assemblages include those based primarily on spinel crystals as well as those based on enstatite and spinel; common accessory phases include Mg-petalite, Mg,Al-titanate solid solutions, quartz solid solutions and rutile. These glass-ceramics can have ultra-fine grain sizes, with spinel crystals less than 25 nm and enstatite crystals less than 100 nm in size. Such nanocrystalline microstructures are unique in the case of an enstatite glass-ceramic and provide extremely smooth polished surfaces, with average roughness of about 5-10 A (0.5-1.0 nm). These materials provide strength and toughness values higher than might otherwise be expected from such a fine-grained microstructure, due in part to the toughening effect of the lamellar twinning in the enstatite phase. The morphology of the initial phase separation provides a template for the ultimate crystalline microstructure, essentially locking in its nanocrystalline nature such that regardless of heat treatment crystals grow no larger than 200 nm. © 1997 Elsevier Science B.V.
Decreased dominance in a limited access test but normal maternal behavior in micrencephalic rats

Micrencephalic offspring produced by gestational treatment with the antimitotic compound methylazoxymethanol acetate (MAM) are remarkable for substantial preservation of function concurrent with severe neural stunting. Altered behaviors in these micrencephalics, including light shyness and response perseveration, are similar to those produced by frontal cortex lesions. Consistent with this, the frontal cortex is one of several regions severely stunted by gestational MAM treatment. Because the frontal cortex has been implicated in rodent social behavior, maternal behavior in females and dominance in both sexes were assessed. Dominance was measured via water competition in 24-h water-deprived dyads (1 control and 1 MAM) matched for sex and body weight. Micrencephalic rats exhibited shorter drinking time than controls (males: 101 vs. 219 s, p < 0.001; females: 114 vs. 176 s, p < 0.03), indicating that micrencephalics were more submissive. For maternal behavior tests, micrencephalic and control females were bred to control males and pup retrieval was measured on postnatal days 3–13. Micrencephalic dams were unimpaired in any aspect of pup retrieval. Of 8 standard behavior measures used here and previously, access time in water competition tests produced the clearest differentiation between control and micrencephalic rats. These studies indicate that at least one aspect of social dominance in both sexes is severely reduced by MAM treatment while maternal behavior remains intact.
Controlling Impact Forces in Pneumatic Robot Hand Designs

Possibilite de regler les forces d'impact dans le cas de la prehension par une main pneumatique de robot
The value of genetic and pharmacological approaches to understanding the complexities of GABAA receptor subtype functions : The anxiolytic effects of benzodiazepines

The identification of gamma-aminobutyric acid A (GABA(A)) receptor subunit genes over the last twenty years has shown that GABA(A) receptors are made up of many different subtypes. As such the dissection of which receptor subtypes mediate which functions of clinically useful GABAergic drugs, such as benzodiazepines, has been extremely complicated. Two complimentary approaches have been taken: the development of subtype-selective drugs and the genetic manipulation of different receptor subunits. Both have yielded exciting results, but sometimes with contradictory findings. This review highlights the strengths and weaknesses of both approaches, illustrating with specific discussion of the work, to uncover which receptor subtype(s) mediates the anxiolytic effects of benzodiazepines.
Prediction and measurement of corrosion inhibition of mild steel using nonionic surfactants in chloride media

As an important corrosion inhibition tool, surfactants have been used widely. Therefore, the prediction of corrosion inhibition by surfactants of varying alkyl hydrocarbon chain lengths in various solution media with different ionic strengths becomes desirable. This article utilizes recently developed methodology and equations to predict mild steel corrosion inhibition by alkanol nonionic surfactants. Also the relationship between surfactant concentration, surfactant critical micelle concentration (cmc), and corrosion inhibition is analyzed in this paper. The results from this paper can be applied to relevant industrial uses of surfactants for corrosion inhibition.
Effects of PEGylation on the preservation of cationic lipid/DNA complexes during freeze-thawing and lyophilization.

ABSTRACT: The incorporation of components with covalently attached polyethylene glycol (PEG) into nonviral vectors has been shown to prevent aggregation in serum and extend the circulating half-life of lipid/DNA complexes (lipoplexes) in vivo . The tendency of synthetic vectors to aggregate during processing and storage also represents a significant obstacle in the development of lipoplexes as marketable pharmaceutical products. The extreme instability of lipoplexes formulated as aqueous suspensions has generated interest in preserving nonviral vectors as frozen or lyophilized formulations. Previous work has demonstrated that stabilizing excipients are capable of protecting lipoplexes during freezing and lyophilization, but there is little known about the ability of PEGylation to protect vectors during these stresses. This study incorporates up to 10% by weight dioleoyl phosphatidylethanolamine conjugated to PEG-2000 and PEG-5000 into lipoplexes and assesses the maintenance of particle size and transfection after agitation, freeze-thawing, and lyophilization. Our results indicate that the incorporation of PEGylated components alone (up to 10% by weight) is insufficient to preserve particle size during these stresses. However, when sucrose was employed in combination with PEGylated components, a small protective effect of PEGylation was observed. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association