cssi/SciSciGPT-SciSciNet huggingface dataset:
The hopf algebra of linearly recursive sequences

We explain how the space of linearly recursive sequences over a field can be considered as a Hopf algebra. The algebra structure is that of divided-power sequences, so we concentrate on the perhaps lesser-known coalgebra (diagonalization) structure. Such a sequence satisfies a minimal recursive relation, whose solution space is the subcoalgebra generated by the sequence. We discuss possible bases for the solution space from the point of view of diagonalization. In particular, we give an algorithm for diagonalizing a sequence in terms of the basis of the coalgebra it generates formed by its images under the difference-operator shift. The computation involves inverting the Hankel matrix of the sequence. We stress the classical connection (say over the real or complex numbers) with formal power series and the theory of linear homogeneous ordinary differential equations. It is hoped that this exposition will encourage the use of Hopf algebraic ideas in the study of certain combinatorial areas of mathematics.
Anomalous surface enhanced molecular Raman scattering from inelastic tunneling spectroscopy junctions

Abstract Anomalously strong Raman spectra have been obtained from molecular monolayers adsorbed on the insulator in metal-insulator-metal tunnel junctions. We show unambiguously that Raman spectroscopy can readily detect molecular monolayers and consider the effects of surface roughness, the molecule-metal interface and the metal on our results.
Progress Toward Improving Animal Models for Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) remains a disease with an unknown cause and a poor prognosis. Among attempts to define disease pathogenesis, animal models of experimental lung fibrosis have a prominent role. Commonly used models include exposure to bleomycin, silica, fluorescein isothiocyanate; irradiation; or expression of specific genes through a viral vector or transgenic system. These all have been instrumental in the study of lung fibrosis, but all have limitations and fall short of recapitulating a pattern of usual interstitial pneumonia, the pathologic correlate to IPF. A model of repetitive bleomycin lung injury has recently been reported that results in marked lung fibrosis, prominent alveolar epithelial cell hyperplasia, a pattern of temporal heterogeneity and persistence of aberrant remodeling well after stimulus removal, representing a significant addition to the collection of animal lung fibrosis models. Taken together, animal models remain a key component in research strategies to better define IPF pathogenesis.
Divergent practices among Catholic hospitals in provision of direct sterilization.

Background The Ethical and Religious Directives for Catholic Health Catholic Care Services (ERDs) are designed to promote uniform practice of health care in accordance with human and Catholic values. The aim of this study was to determine whether the ERDs are being uniformly interpreted and applied. Directive 53 prohibits the provision of direct sterilization. Hospital data were reviewed to determine whether direct sterilizations on women are being performed within Catholic hospitals and their frequency. A significant diversity of practice regarding sterilization would indicate that the ERDs are not uniformly interpreted and applied by Catholic hospitals in the United States. Methods All Catholic hospitals in seven states—California, Illinois, Indiana, New Jersey, New York, Texas, and Washington—were studied to determine whether diversity of practice existed in the provision of direct female sterilization. Inpatient discharge data were requested from the respective departments of health for each state for...
Organophosphorus molecules of the stoichiometry B9H11CPR

Abstract The reaction of 7,8- or 7,9- B9H11CP− with alkyl halides (RX) resulted in molecules of the stoichiometry B9H11CPR. NMR spectra of the products are reported and these data indicate that the R groups are bonded to tile phosphorus.
A brief review of some application driven fast algorithms for elliptic partial differential equations

Some application driven fast algorithms developed by the author and his collaborators for elliptic partial differential equations are briefly reviewed here. Subsequent use of the ideas behind development of these algorithms for further development of other algorithms some of which are currently in progress is briefly mentioned. Serial and parallel implementation of these algorithms and their applications to some pure and applied problems are also briefly reviewed.
Poly(allylamine) Stabilized Iron Oxide Magnetic Nanoparticles

This paper describes a new method for the dispersing and surface-functionalization of metal oxide magnetic nanoparticles (10 nm) with poly(allylamine) (PAA). In this approach, Fe3O4 nanoparticles, prepared with diethanolamine (DEA) as the surface capping agent in diethyleneglycol (DEG) and methanol, are ligand exchanged with PAA. This method allows the dispersing of magnetic nanoparticles into individual or small clusters of 2–5 nanoparticles in aqueous solutions. The resulting nanoparticles are water soluble and stable for months. The PAA stabilized Fe3O4 nanoparticles are characterized by TEM, TGA, and FT-IR. The PAA-coated Fe3O4 nanoparticles will allow further chemical tailoring and engineering of their surfaces for biomedical applications.
Density functional study of the TiO2–dopamine complex

Abstract The binding energies and excitation energies of dopamine interacting with TiO 2 clusters of different sizes representing an anatase surface are calculated. Results indicate that bidentate adsorption of dopamine on undercoordinated sites containing a Ti O double bond is more stable than monodentate or molecular adsorption on the (1 0 1) anatase surface. A large red shift in the absorption spectrum of TiO 2 –dopamine is calculated, in agreement with experimental studies. We also investigate how the optical properties of TiO 2 –dopamine are affected by adding carboxyl thymine and subsequent base pairing with adenine.
Enhanced ablation of small anodes in a carbon nanotube arc plasma

The ablation rate of a graphite anode is investigated as a function of anode diameter for a carbon nanotube arc plasma. It is found that anomalously high ablation occurs for small anode diameters. This result is explained by the formation of a positive anode sheath. The increased ablation rate due to this positive anode sheath could imply greater production rate for carbon nanotubes.
Molecular tools for chemical biotechnology

Biotechnological production of high value chemical products increasingly involves engineering in vivo multi-enzyme pathways and host metabolism. Recent approaches to these engineering objectives have made use of molecular tools to advance de novo pathway identification, tunable enzyme expression, and rapid pathway construction. Molecular tools also enable optimization of single enzymes and entire genomes through diversity generation and screening, whole cell analytics, and synthetic metabolic control networks. In this review, we focus on advanced molecular tools and their applications to engineered pathways in host organisms, highlighting the degree to which each tool is generalizable.
Approaches that exploit vector-parallelism for three rendering and volume visualization techniques

Abstract Direct volume rendering using volume ray-casting and indirect volume rendering using the Marching Cubes isosurface extraction are popular techniques for volume visualization. Surface ray-tracing is a popular graphics technique for rendering scenes composed of well-defined surface primitives. However, these techniques are relatively computationally intensive. Thus, near-real-time computational performance is a difficult goal. This paper presents approaches to these rendering and volume visualization techniques that are tuned for efficient performance on a vector-parallel supercomputer. The approaches decompose and reconstruct the techniques to exploit inherent data parallelism and the specific characteristics of the CPU. Experimental results for several datasets are also exhibited.
A method for the increased extraction of cholesterol from human red blood cells by modified plasma lipoprotein.

Abstract The in vitro extraction of cholesterol from erythrocytes by plasma lipoproteins of reduced cholesterol content would be expected to be free of cholesterol-unrelated alterations of the cell membrane. The earlier application of this method utilized whole blood plasma in which the major part of the lipoprotein cholesterol was esterified by the plasma enzyme lecithin-cholesterol acyl transferase (LCAT) in a preliminary incubation. Because of the cholesterol remaining unesterified in the plasma, only 35% of the cell cholesterol could be removed. The method reported here uses HDL., a plasma lipoprotein which is the preferred substrate for LCAT, instead of whole plasma for the extraction. Multiple extractions with LCAT treated HDL, resulted in the removal of up to 77% of the erythrocyte cholesterol with only minor hemolysis.
Metrizability, monotone normality, and other strong properties in trees

Abstract Metrizability is an extremely strong property where trees are concerned, and it turns out that in many ways, monotone normality is the appropriate generalization when the trees have uncountable chains. We show that monotone normality is equivalent to the tree being the topological direct sum of ordinal spaces, each of which is a convex chain in the tree. Several metrization theorems are proven, some in ZFC, some just assuming ZF or “ZF + Countable AC”, and still others assuming ZFC-independent axioms, as well as theorems in a similar spirit with monotone normality of the tree as a conclusion. The property of being collectionwise Hausdorff plays a key role, and we obtain partial results on the still unsolved problems of whether it is consistent that every collectionwise Hausdorff tree or every normal tree is monotone normal.
The Sustainability and Optimality of Government Debt

The sustainability and optimality rules for government debt are derived within an intertemporal optimizing framework in which both capital and government debt are endogenous, driven by utility and profit-maximizing behavior of private agents and tax and expenditure policies of the government. The rules are expressed purely in terms of familiar economic parameters, and their ready applicability in an operational context is illustrated by instructive numerical examples. A discussion of the relationship between the optimality rule and the "golden rule" of savings in the literature is also provided.
On iterative refinement of triangular linear algebraic systems

Abstract In this paper the “convergence” of an iterative refinement procedure for solving triangular linear algebraic systems is proved. The application of this procedure to the “accurate” LU decomposition of near-singular systems is described. A simple numerical example illustrates the theory.
Characterization of pulsed-plasma-polymerized aromatic films

Pulsed plasma polymerization is used to produce aromatic thin films from inductively coupled rf plasmas with benzene, 1,2,4-trifluorobenzene, and hexafluorobenzene as monomers. The effects of aroma...
Radioisotope-powered free-piston Stirling engine for space applications

Abstract The paper presents a preliminary conceptual design of a 2kW(e) autonomous power system consisting of a radioisotopic heat source, free-piston Stirling engine, reciprocating induction generator and a space radiator. The proposed design features a direct thermal interfacing of the Pu-238 heat source with the Stirling engine head, low heat losses during normal operation, and provides an auxiliary/emergency cooling system in the case of the engine failure of stopping. The Stirling engine is of the free-displacer, free-piston type invented by Beale and uses helium as the working fluid. The engine piston is integrated with the armature of a simple linear alternator which is used for electric generation. Waste heat is rejected by a four-finned space radiator sized for a geosynchronous orbit. Specific power and efficiency of the Stirling isotope power system are compared with the present and predicted performance of other power conversion systems suitable for the same power range.
Maximum entropy image reconstruction from projections via Lagrange parameter analysis

A method for maximum-entropy image reconstruction from projections is presented. Two image entropies are studied under the assumption that image-density distributions over image-element array follow a multinomial random process. The multinomial distribution process reflects those physical aspects of images: (1) image density is non-negative, (2) image-density distributions are conserved, (3) image-density distributions are spatially correlated. One image entropy assumes a uniform spatial correlation and resembles Shannon's entropy that has been widely used in image-processing problems. The other assumes non-uniform spatial correlations among nearby image elements and resembles the cross entropy introduced by Kuilback and Leibler. The non-uniform correlations among nearby elements are modeled in a similar manner as Markov random field does, i.e., image density changes slowly within a homogeneous region and rapidly at the boundaries of the homogeneous regions. The projections are assumed as measured by a linear imaging system. The measurement constraints are incorporated into the maximum-entropy method by employing a set of Lagrange parameters. Each Lagrange parameter is related to a constraint of a datum. The solutions that maximize the image entropies subject to the measurement constraints are given, as determined respectively by a superposition of the Lagrange parameters. The Lagrange parameters are then estimated iteratively using a steepest descent technique. Comparative study on the image entropies is carried out using computer generated noise-free and noisy projections. Improved results are obtained by use of the image entropy assuming the non-uniform correlations. The non-uniform correlated image entropy needs little more computation time and memory.
Saphenous Vein Coronary Artery Bypass in Patients with "Preinfarction Angina"

Among the first 400 patients undergoing saphenous vein coronary artery bypass at Stanford Medical Center, 67 (18%) met criteria for "preinfarction angina". Angina was alleviated and possible myocardial infarction was prevented utilizing these surgical technics. The overall operative mortality rate in the preinfarction angina patients was 10.4%, which contrasted strikingly with a 1.5% operative mortality for elective coronary artery bypass at Stanford. Six of the seven operative deaths resulted from myocardial infarction, two of which were related to technical factors. Operative mortality appeared to be related to degree of preoperative congestive heart failure and hypotension, pump time, sex, and number of atherosclerosis risk factors present. Fifty-two of the 60 patients leaving the hospital (87%) received good symptomatic benefit from surgery, including no late infarction, over a 6.8 month mean follow-ulp period. The late death rate was 3.3%, and the late infarction rate was 10% during the follow-up per...
Cross-Talk between Altitude Changes and Speed Control during Simulated Low-Altitude Flight

Simulations of flight over a planar environment create an ambiguous optical stimulus in which changes in altitude can potentially induce inappropriate control of speed. Previous research has shown that changes in altitude produce changes in global optical flow rate that lead to erroneous judgments of speed and increased RMS error in speed control. However, from these studies it is unclear whether erroneous speed control was directly due to misperceiving changes in altitude as changes in speed or simply a response to more complex optical flow masking the optical effects of speed changes. Our experiment used a speed maintenance task during simulated flight over a planar surface to examine the effect of changes in altitude on control of speed. We found that power in participants' speed control input increased at the specific frequencies of the simulated altitude changes relative to power at those same frequencies when no altitude disturbance was present. These results clearly show that controllers respond to...
At the Café de los Cachuchas: Frida Kahlo in the 1920s

This essay proposes new readings of two of Frida Kahlo's most important early paintings, done after the bus accident that truncated her studies at the Escuela Nacional Preparatoria. An unfinished picture of around 1927, erroneously known as "Pancho Villa and Adelita", is not fundamentally about the Revolution; rather, seen in context with related images, it is an attempt by Kahlo to imagine herself and her high school classmates (the 'Cachuchas') as members of an avant-garde artistic group performing in an urban cafe. The essay also closely examines an innovative 1927 portrait of her close friend and fellow 'Cachucha', the poet Miguel N. Lira. Although these experimental works are less famous than her later iconic paintings, they help expand our understanding of how Kahlo found her mature artistic style. The visual innovations of these two works are also contrasted with Kahlo's contemporaneous watercolours showing quaint scenes in Coyoacan, inspired by the children's art programmes of the Education Ministry. In the mid-1920s, Kahlo viewed rural Mexico as a place of melancholic isolation, while the capital was a place for exciting intellectual exchange, a privileging of city over country that she would invert by the early 1930s.
A Field and Chemical Study of Serpentinization—Stonyford, California: Chemical Flux and Mass Balance

Serpentinized harzburgites and dunites in the Coast Range ophiolite near Stonyford, California, form massive, decameter- to kilometer-scale blocks in serpentinite schist; together these form serpentinite broken formation that grades into melange where exotic blocks have been incorporated into the serpeninite schist. Whole rock geochemical data and modal reconstruction of protolith compositions show that serpentinization here proceeded essentially isochemically for Si, Mg, and Fe, whereas other elements (Ca, Al, Cr) were lost to an aqueous flux. Mass balance calculations based on actual primary and secondary mineral compositions show that significant Fe, Al, and Cr may be accommodated in serpentine. The transformation of orthopyroxene to serpentine (bastite) releases significant amounts of silica, which forms additional serpentine when it reacts with MgO released by the serpentinization olivine; this reaction suppressed brucite formation and accounts in part for the conservation of silica and magnesia docu...
Transesophageal Echocardiography in Patients With Esophageal Varices

Transesophageal echocardiography (TEE) has proved invaluable in the evaluation of a number of conditions, including stroke, endocarditis, prosthetic valves, and acute aortic syndromes, as well as in the preoperative and perioperative evaluation of valvular heart disease. 1 The value of TEE must of course be balanced against the risk of performing the procedure. The insertion and manipulation of a transesophagealechocardiographic probemay infrequentlycausepharyngeal, esophageal, or gastric trauma. Screening for esophageal pathology by history and review of the medical record is an essential component of evaluation before performing TEE. Patients with esophageal stricture, esophageal cancer, esophageal diverticulum, and recent esophageal surgery are generally considered to have near absolute contraindications for TEE. Esophageal varices have been considered an absolute as well as a relative contraindication to TEE, depending on the center and/or operator. Esophageal varices develop to decompress the hypertensive portal veincirculationthatresultsfromobstructiontoportalvenousoutflow; cirrhosis is the most common cause. In prospective studies using fiber optic endoscopy, new varices develop at a rate of 5% in thefirst year. 2 Twenty-eight percent of patients with cirrhosis have varices at 3 years. 2 It is clear that variceal bleeding carries significant morbidity in patients with cirrhosis. A number of factors have been demonstrated on esophagogastroendoscopy to predict the likelihood of variceal hemorrhage, including the location, size, and appearance of the varices. In addition, several clinical features of individual patients portend a greater variceal bleeding risk. Experienced echocardiography laboratories usually do not consider esophageal varices an absolute contraindication to TEE, but the potential added information should be weighed against the risk for provoking a major upper gastroesophageal bleed. In this issue of the Journal of American Society of Echocardiography, Spier et al 3 report a retrospective analysis of the complications of performing TEE in a series of patients with known gastroesophageal varices. Physicians who perform TEE need to make individualized decisions on the risk/benefit ratio of performing TEE in patients with known or suspected varices. When evaluating the risk, a number of issues should be considered, including the grade of the varices, clinical history of gastroesophageal bleeding, and evidence of coagulopathy (platelet count and international normalized ratio [INR] for prothrombin time). The fact that no reported case of upper variceal
Rolling deformation of two-ductile-phase AgNi alloys

Abstract The AgNi alloy system is a model system for the investigation of two-ductile-phase deformation, due to its simplicity. Alloys are composed of ductile Ag and Ni phases. Three AgNi alloys were examined: 25 vol.% Ni phase, 50% Ni, and 75% Ni. These alloys were cold rolled to an 80% reduction in thickness. The 50% Ni alloy was cold rolled to reductions in thickness of 20, 40, 60, 80, and 90%. Phase boundary surface area per unit volume and Ni phase dimensions were measured quantitatively. Using a quantitative microscopy approach, phase strains resultant in the Ni phase were defined and measured as a function of cold rolling reduction and phase volume fraction. Comparison with the overall strain indicated that the harder Ni phase strained less than the overall strain. This is suggestive of the occurrence of phase strain partitioning in the two-ductile-phase alloy.
Myocardial ischemia associated with clenbuterol abuse: report of two cases.

Abstract Background Clenbuterol is an orally administered long-acting beta-2 adrenergic agonist closely related to albuterol that, in recent years, has become a substance of abuse in the bodybuilding and athletic community. Objectives We report two cases of acute myocardial ischemia associated with clenbuterol abuse in two healthy young male body builders. Case Report Two male bodybuilders, ages 18 and 22 years, presented to the Emergency Department with palpitations, nausea, vomiting, chest pain, diaphoresis, and tachycardia shortly after ingesting clenbuterol. Both patients experienced prolonged sinus tachycardia that, in one patient, was relatively resistant to both beta- and calcium channel blockade. Both patients were found to have elevated troponin levels, the first patient as high as 4.71 ng/mL (normal Conclusions Emergency physicians should be aware of the clinical presentation of clenbuterol abuse and overdose, and the possibility of related cardiac ischemia and rhythm disturbances. Suggested treatment includes intravenous fluids, oxygen, aspirin, beta-blockers, and benzodiazepines, although efficacy remains unproven.
Guest Editor's Introduction: Visualization for Cybersecurity

The guest editor introduces this special issue. The five theme articles highlight the latest development and practice for visualization for cybersecurity.
Why the Southern Hemisphere ENSO responses lead ENSO

[1] Analysis of observational estimates indicates that the El Nino–Southern Oscillation (ENSO) forced pattern in the extratropical Southern Hemisphere (SH), somewhat surprisingly, leads the peak phase of ENSO by one season. A Rossby wave source (RWS) analysis indicates that the tropical and extratropical RWS in the SH develops before the ENSO peak season and abruptly weakens thereafter. Further analysis shows that anomalous divergence/convergence and corresponding irrotational wind anomalies are sensitive to local seasonality. Numerical experiments in which the tropical Pacific is prescribed with perfectly periodic ENSO while all other oceans are simulated as a slab mixed layer model coupled to AGCM also show similar features. Additional numerical experiments in which ENSO forcing is shifted by 6 months (i.e., the ENSO peak in the southern winter season) indicate that the Northern Hemisphere atmosphere rather than the SH atmosphere precedes ENSO. This result supports the hypothesis that the ENSO forced pattern in the extratropics is strongly limited by local seasonality, rather than by the temporal phase of tropical remote forcing.
A proposed test of two hypotheses related to concentration fluctuations and residence times

An experimental test is proposed of the hypotheses behind 2 models of Junge's empirical result relating fluctuations in concentrations of atmospheric trace constituents to their residence times. DOI: 10.1034/j.1600-0889.1990.t01-1-00009.x
Breath testing and highway fatality rates

This paper presents an empirical investigation of the effect of a preliminary breath test law on highway fatality rates. A preliminary breath test law reduces the procedural problems associated with obtaining evidence of drunk driving and thus increases the probability that a drunk driver will be arrested. According to the theory of deterrence, increasing the probability of arrest for drunk driving will reduce the occurrence of this behaviour. The data set employed to test the theory is a time series from 1980 to 1985 of cross sections of the 48 contiguous states of the United States. Four highway fatality rates are used as measures of drunk driving. The effect of the breath test law was estimated using four independent variable models and 12 dummy variable models. The four independent variable models were also estimated using Learner's specification test. The purpose of using these alternative specifications and Learner's specification test was to examine the breath test coefficients for specification bi...
Activation of Ionotropic Glutamate Receptors using Tethered Photoswitchable Ligands

Ionotropic glutamate receptors (iGluRs) are ligand-gated ion channels, which mediate and modulate excitatory neurotransmission in the central nervous system. iGluRs are tetramers that are formed by identical or homologous subunits, but little is known about how ligand binding at individual subunits contributes to gating. Here we address this question using photoswitchable ligands that are tethered to specifically introduced cysteine residues. The ligand, termed MAG, consists of a cysteine-reactive maleimide group, an azobenzene photoswitch, and a glutamate analogue as head group. After coupling to an attachment site close to the binding cleft, light of specific wavelengths can be used to switch MAG between its cis and trans form, which allows to control ligand binding and unbinding with high temporal precision. We combined photoswitching with voltage-clamp recordings to measure the effect of partial receptor occupation on the extent and time course of activation and desensitization in GluK2, a member of the kainate receptor family. Extending these experiments to heteromeric complexes and complexes of defined subunit stochiometry will provide further information on how individual subunits contribute to the activation, deactivation and desensitization of this important class of signaling molecules.
Fluorescent paint for measurement of heat transfer in shock - turbulent boundary layer interaction

Abstract The principles of the fluorescent paint technique for surface heat transfer measurement are presented. This technique allows determination of the heat transfer from a surface with good accuracy and high spatial resolution. To examine the capabilities of this technique, the temperature-sensitive paint is used to visualize and measure heat transfer in several typical shock-turbulent boundary layer interactions. Quantitative comparison of the measured heat transfer with existing data obtained using conventional methods is discussed.
On the performance and parameter problems of approximate molecular orbital theory, with comparative calculations on the carbon monoxide molecule

A theoretically correct breakdown of the molecular wave function into Hartree-Fock and electron correlation components leads to the identification of four parameter problems important in approximate molecular orbital theory. The effects of the intramolecular environment on isolated atom optimized atomic orbitals, the deviation of simple basis atomic orbitals from true Hartree-Fock atomic orbitals, differences made in transforming to a basis of orthogonal atomic orbitals, and the estimation of the molecular electron correlation energy are considered. Order-of-magnitude corrections are suggested for each of these problems. Comparative NDDO all electron calculations on the carbon monoxide molecule illustrate the improved results obtained. Additional information on the performance of methods more approximate than the NDDO all electron one indicates that quantitatively they leave much to be desired.
Vanadium alloys for fusion reactor applications

Fusion reactors will produce a severe operating environment for structural materials. The material should have good mechanical strength and ductility to high temperature, be corrosion resistant to the local environment, have attractive thermophysical properties to accommodate high heat loads, and be resistant to neutron damage. Vanadium alloys are being developed for such applications, and they exhibit desirable properties in many areas. Recent progress in vanadium alloy development indicates good strength and ductility to 700°C, minimal degradation by neutron irradiation, and reduced radioactivity compared with other candidate alloy systems.
A combinatorial proof of Cayley's theorem on Pfaffians*

Abstract Cayley's theorem, published in 1847, asserts that any skew-symmetric determinant of even order is equal to the square of its Pfaffian. A proof of this result, depending on the combinatorial structures of determinants and Pfaffians, is presented here. It emerges that the theorem holds, essentially because the representation of a permutation of [1, 2,…, 2 m] as a product of disjoint cycles of odd parity relates it biuniquely to two independent partitions of the same set into pairs, while a permutation whose cyclic representation contains cycles of even parity corresponds to a term of the determinant which is eliminated by skew-symmetry.
Neuroimaging of Nicotine Dependence: Key Findings and Application to the Study of Smoking–Mental Illness Co-morbidity

Modern neuroimaging techniques offer the opportunity to noninvasively study neuroanatomical and neurofunctional correlates of nicotine dependence and its treatment. In the present review, the most widely used neuroimaging techniques—magnetic resonance imaging (MRI), positron emission tomography, and functional MRI—are briefly described and their strengths and limitations discussed. The use of these techniques has resulted in new insights into the neuropharmacology of tobacco addiction. Studies comparing smokers and nonsmokers have shown that smokers have less grey matter density in frontal brain regions and greater concentrations of nicotinic receptors. Research on the effects of smoking a cigarette confirms that smoking leads to the release of dopamine in brain reward areas and to nicotinic receptor binding. Studies of smoking abstinence have identified functional brain correlates of increased reactivity to smoking-related cues, and worsening of concentration. To date, neuroimaging studies of nicotine de...
The full multi-state vector error covariance matrix: why needed and its practical representation

Whether statistically representing the errors in the estimates of sensor metadata associated with a set of images, or statistically representing the errors in the estimates of 3D location associated with a set of ground points, the corresponding “full” multi-state vector error covariance matrix is critical to exploitation of the data. For sensor metadata, the individual state vectors typically correspond to sensor position and attitude of an image. These state vectors, along with their corresponding full error covariance matrix, are required for optimal down-stream exploitation of the image(s), such as for the stereo extraction of a 3D target location and its corresponding predicted accuracy. In this example, the full error covariance matrix statistically represents the sensor errors for each of the two images as well as the correlation (similarity) of errors between the two images. For ground locations, the individual state vectors typically correspond to 3D location. The corresponding full error covariance matrix statistically represents the location errors in each of the ground points as well as the correlation (similarity) of errors between any pair of the ground points. It is required in order to compute reliable estimates of relative accuracy between arbitrary ground point pairs, and for the proper weighting of the ground points when used as control, in for example, a fusion process. This paper details the above, and presents practical methods for the representation of the full error covariance matrix, ranging from direct representation with large bandwidth requirements, to high-fidelity approximation methods with small bandwidth requirements.
Organization of crustacean epizoan communities in a chain of subalpine ponds

Crustacean zooplankton in high altitude ponds in Colorado support two suites of epizoans. Epizoans on Daphnia consisted of Colacium calvum, Characium gracilipes, and peritrich ciliates. Epizoans on Ceriodaphnia, Scapholeberis, and Eucyclops involved Colacium vesiculosum and the peritrich ciliates. Frequent, regular molting of most of the substrate organisms keeps attachment surfaces unoccupied. Epizoan attachment is site-specific rather than a function of epizoan-epizoan interaction. The presence of phototrophic epizoans may contribute to increased susceptibility of their substrate organisms to fish predation.
RESTful Massively Multi-user Virtual Environments: A feasibility study

The increased bandwidth made available to consumers in the past decade has enabled the spread of Massively Multi-user Virtual Environments (MMVEs). MMVEs require fast and frequent updates to be delivered to a considerable number of users. To address these difficult requirements, developers resort to network architectures tightly coupling clients and servers. While providing a good enough quality of experience, these architectures often compromise scalability and fault tolerance, and limit the design of user interactions and gameplay. To gain scalability and fault tolerance back, we investigate the possibility of developing MMVEs using the REST principles. Our theoretical and experimental results show that MMVEs can be built in a REST style, providing that new data management systems are developed.
Contingent discrimination in humans.

Six groups of 10 human Ss, 14- to 18-yr.-old, performed 4-display contingent discrimination tasks in which reinforcement was governed by 1 of 2 possible extra stimuli added to otherwise conventional discrimination displays. Each extra stimulus was related either to the identity or the position of the correct choice. Few errors occurred when identity of correct choice was relevant, but many more errors and some failures to reach criterion occurred when position of correct choice was relevant for some or all of the displays.
Sirt1 as a key regulator orchestrating the response to caloric restriction

Although it was discovered more than 70 years ago that caloric restriction (CR) extends the life span of rodents, the molecular basis of CR has remained obscure. Recently, NAD-dependent Sir2 deacetylases have emerged as key regulators that mediate the adaptive response to CR. Here, we describe the tissue-dependent functions of the mammalian Sir2 ortholog, Sirt1/Sir2α and present a molecular framework in which Sirt1 orchestrates multiple physiological changes into a coordinated response to CR in mammals.
Attenuation of iNOS in an LPS-Stimulated Macrophage Model by Omega-3 Fatty Acids is Independent of COX-2 Derived PGE2

Background Omega-3 fatty acids (n-3 FA) demonstrate significant anti-inflammatory properties thought to occur through three principal mechanisms; (1) displacement of arachidonic acid from the cellular membrane, (2) differential prostaglandin E 2 (PGE 2 ) and LTB 4 production, and (3) molecular level alterations such as diminished nuclear factor kappa B and AP-1 activation. Recently, n-3 FA have been demonstrated to significantly decrease nitric oxide (NO) production in a lipopolysaccharide (LPS)-stimulated MΦ model. We hypothesized that decreased NO production by n-3 FA occurs through inhibition of cyclooxygenase-2 (COX-2) derived PGE 2 and that repletion of the system with PGE 2 would obliterate these effects. Selective COX-2 inhibitor (L-748,731) experiments and separate PGE 2 repletion studies were used to test this hypothesis. Methods NO production was assessed following 24 h with or without LPS/PGE 2 in the presence of n-3 FA, L-748,731 (a selective COX-2 inhibitor), or combination (n-3 FA + L-748,731) treatment. Western blots were used to assess inducible NO synthase protein expression. Results Independently or in the presence of LPS, treatment with a COX-2 inhibitor significantly increased NO production compared with control, n-3 FA, and combination treatment. NO production in combination treatment is slightly increased compared to n-3 FA treatment. In control cells treated with LPS, PGE 2 repletion resulted in a significant decrease in NO. All other treatment groups repleted with PGE 2 demonstrated no significant alterations in NO production. Inducible NO synthase protein expression levels were similar to NO production across all treatments. Conclusion These experiments disproved our original hypothesis that the decrease in NO production associated with n-3 FA treatment occurs through a COX-2 derived PGE 2 dependent mechanism. Eliminating COX-2 derived PGE 2 by a selective inhibitor actually increased NO production. Exogenous PGE 2 repletion did not restore the system. Therefore, mechanisms other than n-3 FA associated alterations in COX-2 derived PGE 2 are likely involved in decreasing NO production in LPS stimulated MΦ.
Thought Control: Is It Ability, Strategies, or Both That Predicts Posttraumatic Symptomatology in Victims of Interpersonal Trauma?

Cognitive models of PTSD have implicated thought control in the development, maintenance, and recovery from PTSD. The present study extends previous research on thought control (ability and strategies) and it’s relation to posttraumatic stress symptoms (PTSS) in a sample of interpersonal trauma (IPT) survivors. Results revealed that weak thought control ability mediated the relationship between accumulated discrete IPT experiences and PTSS severity. Weak thought control ability was associated with greater use of thought control strategies, and thought control strategies of punishment and suppression added significant variance over and above the effects of accumulated IPT experiences and thought control ability in predicting PTSS severity. Furthermore, weak thought control ability was related to greater PTSS severity through the use of punishment and suppression thought control strategies. The present findings extend previous research and provide further support for theoretical assumptions of current treatment approaches for PTSD.
Homogeneous doping of ceramics by infiltration–gelation

Abstract Advanced ceramics require small amounts of cation dopants to improve the sintering process or achieve certain properties. Dopant precursors are often dissolved in initial processing liquids, which may adversely affect ceramic colloidal stability, and dopant transport during drying. This would lead to chemical and microstructural inhomogeniety in the eventual ceramics. Here we present a method that circumvents these problems using the example of Al3+-doped TiO2 ceramics. Homogeneous TiO2 compacts with 34% porosity are first prepared by colloidal casting and calcined at 700 °C. The obtained compacts are infiltrated with an aqueous solution of Al(NO3)3, citric acid and ethylene glycol. The solution composition is adjusted such that during drying, a gel forms that covers the internal pore surface. Subsequent decomposition of organics results in a homogeneous dopant distribution in the porous and then dense-sintered TiO2 compacts. This is verified with SEM-EDX, and laser ablation coupled ICP-MS on dense compacts sintered at 1100 °C.
Studying Polymer-Dispersed Liquid-Crystal Formation by FTIR Spectroscopy. 1. Monitoring Curing Reactions

UV-induced matrix cross-linking is the method of choice to form polymer-dispersed liquid crystals (PDLCs). In this paper, real-time FTIR spectroscopy is applied to study the curing of a model systema thiolene-chemistry-based prepolymer (NOA65) and its mixtures with liquid crystals. Curing reactions of NOA65 were examined as a function of the film thickness, temperature, and liquid-crystal content. While there was little dependence of the curing behavior on the thickness of the film, the effect of temperature was strong. Curing rates exhibit a maximum around 325 K, while conversions reach a plateau about 20 K higher. The effect of liquid-crystal addition reveals a depression in the conversion. However, compared to the neat matrix, the final conversion was found to be significantly lower only for phase-separating concentrations. The rate of reaction decreased, and the induction period for the onset of polymerizing reactions increased with increasing liquid-crystal concentration. Real-time FTIR spectroscopy ...
The Impact of the Ford Fellowship Program in the Creation of Latina/o Academic Generations

This article presents preliminary data to examine the manner in which the Ford Fellows Program intellectually and academically affects American higher education and especially those awards afforded...
Novel ultrasonic dynamic focusing system with reduced hardware complexity

Dynamic focusing is known to be the best way to improve image resolution, but it needs very complex and bulky hardware for an array transducer with a large number of elements, such as a sector phased array with 128 elements or a two-dimensional array with more elements. We describe an efficient architecture for ultrasonic dynamic focusing using both analog and digital processing techniques to minimize the hardware complexity. This new focusing hardware consists of a specially designed analog first-in-first-out (AFIFO) device, one for each element, a sampling clock generator (SCG), and a simple multi-input analog adder for a whole system. The SCG generates nonuniform sampling clocks to adjust the sampling instances of the input pulse echo of each AFIFO corresponding to the propagation times between the array element and each imaging point. The AFIFO stores and outputs analog values of these samples on a first-in first-out basis. Finally, the outputs of AFIFOs are summed together by the analog adder. We discuss the hardware reduction ratio of the proposed architecture compared with conventional ones. Preliminary experimental results also are presented.
Foreign Language Programmed Materials: 1966*

like "sleep learning" or, worse, if it actually enables a student to learn anything, it will dehumanize the school and the student in the process. To believers, programmed instruction is the democratic analog of the personal tutor in a mass society. To this group it is a technological panacea in pedagogy based on the crux of the teaching situation, viz., the nature of the learning process. As a potential user of programs, in a teacher or student capacity, one need not espouse either extreme position. Language teachers and students should, however, know what programmed instruction is, and what it has to offer in the foreign language field. Briefly, the essence of this new educational technology is that: (1) course objectives are specified in advance, in detail, and in behavioral terms; (2) the material is presented as a graduated sequence of small items (called frames) leading to the desired terminal behavior; (3) the individual student actively responds at his own pace to each frame (with low probability of error); (4) the student receives immediate reinforcement after each response (principally by finding out whether his previous response was correct). Detailed descriptions of the application of programmed instruction to foreign languages exist1 so as to make an additional one here superfluous. Instead, this article's main intent is to list available programmed materials along with certain items of information about each.
Acetyltransfer Precedes Uridylyltransfer in the Formation of UDP-N-acetylglucosamine in Separable Active Sites of the Bifunctional GlmU Protein of Escherichia Coli

The GlmU protein is a bifunctional enzyme with both acetyltransferase and uridylyltransferase (pyrophosphorylase) activities which catalyzes the transformation of glucosamine-1-P, UTP, and acetyl-CoA to UDP-N-acetylglucosamine [Mengin-Lecreulx, D., & van Heijenoort, J. (1994) J. Bacteriol. 176, 5788−5795], a fundamental precursor in bacterial peptidoglycan biosynthesis and the source of activated N-acetylglucosamine in lipopolysaccharide biosynthesis in Gram-negative bacteria. In the work described here, the GlmU protein and truncation variants of GlmU (N- and C-terminal) were purified and kinetically characterized for substrate specificity and reaction order. It was determined that the GlmU protein first catalyzed acetyltransfer followed by uridylyltransfer. The N-terminal portion of the enzyme was capable of only uridylyltransfer, and the C-terminus catalyzed only acetyltransfer. GlmU demonstrated a 12-fold kinetic preference (kcat/Km, 3.1 × 105 versus 2.5 × 104 L·mol-1·s-1) for acetyltransfer from acet...
Photonic Crystal Waveguides: From Passive to Active, Even to Odd, and Rough to Fine

This talk will review our recent work on photonic crystal waveguide structures and devices including: active slow-light structures/devices, new opportunities in odd modes, and theory and insight on roughness-induced scattering loss. Future opportunities will be discussed.
Individual differences in the improvement of cocaine-induced place preference response by the 5-HT2C receptor antagonist SB242084 in rats

Rationale and objectives The 5-HT2A and 5-HT2C receptors have been shown to be differentially involved in modulating cocaine-induced behaviors. In this study we investigated the effects of the 5-HT2A antagonist MDL100907 (0.3 mg/kg, i.p.) and the 5-HT2C antagonist SB242084 (0.5 mg/kg, i.p.) on development, expression, and recall of cocaine-induced conditioned place preference (CPP) in high- (HR) and low-responder (LR) rats to novelty.
Walking for exercise testing and training.

Le but de cet article est de presenter la marche a pied comme une modalite pour tester l'exercice physique, de fournir un guide pour prescrire des programmes de marche et de recapituler la sante potentielle et les benefices de la marche
Professional development of women and the executive MBA

This study demonstrated that women EMBA graduates experience broadened perspectives. They “think more broadly”, “understand more comprehensively” and report the “life changing” outcomes expected by their sponsoring organizations. The focus was on the development of women managers from specialist perspectives to a more integrated generalist perspective. Personal development, and career development literatures provided the theoretical basis for this study. Data were collected using invited essays, and semi‐structured interviews. Evidence of change appeared in the essays and the interviews. The essays indicated graduates experienced increased confidence, cognitive flexibility, and broadened perspectives. The interviews indicated: greater self‐determination, more flexible approaches to roles, greater value of self and time, more process‐oriented, increased understanding of self and others, the meaning of success was competence, and that competence was valued over political gamesmanship.