cssi/SciSciGPT-SciSciNet huggingface dataset:
Separation of acetanilide and its hydroxylated metabolites and quantitative determination of “acetanilide 4-hydroxylase activity” by high-pressure liquid chromatography

Abstract A simple and very sensitive method for the separation of 4-hydroxyacetanilide, 3-hydroxyacetanilide, 2-hydroxyacetanilide, and acetanilide was developed with the use of high-pressure liquid chromagraphy. Each of these phenolic derivatives can be separated completely from acetanilide and from one another. A simple assay for “acetanilide 4-hydroxylase activity” is thus described. The limit of sensitivity for cytochrome P-450-mediated acetanilide 4-hydroxylase activity is estimated to be 1.0 pmol/min/mg microsomal protein, thereby allowing this assay to be useful in detecting monooxygenase activity in “low level” nonhepatic tissues. Hepatic acetanilide 4-hydroxylase activity is induced about fourfold in C57BL 6N mice by 3-methylcholanthrene. Although acetanilide 2-hydroxylase activity is about seven times lower than the 4-hydroxylase activity, the 2-hydroxylase is also induced about three- or fourfold in C57BL 6N mice by 3-methylcholanthrene. The “2-hydroxylase activity” cannot, however, be strictly quantitated under the conditions described herein. The Km values of both the 3-methylcholanthrene-induced and control 4-hydroxylase activity are about 0.55 m m ; Vmax values for 3-methylcholanthrene-treated and control mice, respectively, are 4.9 ± 1.1 and 1.1 ± 0.31 nmol/min/mg microsomal protein. The 4-hydroxylase in the liver of both 3-methylcholanthrene-treated and control mice appears to represent two or more catalytic activities, i.e., two or more forms of P-450 having widely differing affinities for the substrate acetanilide.
ATSDR's information databases to support human health risk assessment of hazardous substances

The American public, like persons in many other nations, is concerned about the potential adverse impacts of uncontrolled hazardous wastes. The concerns are often predicated on the fear that adverse health effects will occur because of releases of hazardous substances into community environments. To respond to these concerns, government agencies and private sector organizations must rely on credible, accessible, up-to-date information databases. These databases should be relevant to the needs of the people who respond to uncontrolled releases of hazardous substances. Of particular importance are databases that profile the toxicity of hazardous substances and other information useful to physicians and other health care providers. This paper describes how the federal Agency for Toxic Substances and Disease Registry (ATSDR) has developed several toxicologic and human health information databases under mandates in the Superfund statute for responding to the public's concerns about hazardous substances.
Conditional dynamic equivalence of free Yang-Mills fields and free gravitational fields

Abstract It is found that free Yang-Mills fields operating either on Dirac spin space or on the Lie algebra space of local homogeneous Lorentz transformations are dynamically equivalent to free Einstein gravitational fields, if the mapping between Riemannian event space and the Yang-Mills potentials is one to one, up to uniform scale transformations.
Blood and pituitary prolactin levels in tilapia (Sarotherodon mossambicus; Teleostei) from different salinities as measured by a homologous radioimmunoassay.

Highly purified prolactin (PRL) of the tilapia (t), Sarotherodon mossambicus, was injected into rats to produce antibodies. A satisfactory antiserum to the tPRL was used to develop a homologous radioimmunoassay (RIA) in which 125I-tPRL was used as the label. The RIA sensitivity (minimal detectable dose) was 0.8 ng of tPRL standard per milliliter. Specificity of the assay was established by demonstrating negligible cross-reactivity of the antiserum with highly purified tilapia growth hormone, a gonadotropin fraction from tilapia pituitaries, and serum from hypophysectomized Sarotherodon. Furthermore, the RIA disclosed that tPRL is highly concentrated in the rostral pars distalis of tilapia kept in either fresh water (FW) or artificial seawater (ASW). The content of immunoreactive tPRL was 6–10 times greater in pituitaries of FW-adapted fish than in glands of those kept in ASW. Serum levels of tPRL were low in fish kept in 100% ASW and they increased 7- to 12-fold with adaptation to FW. Lowering the environmental salinity from 100 to 30% ASW increased the serum level of tPRL only slightly; the major increase in serum PRL concentration in response to hypotonic medium occurs when the environmental salinity is lowered below 10% ASW. Fish adapted to 100% ASW lacking either CaCl2 or MgCl2 did not show elevated serum PRL levels. These results indicated that in tilapia a major stimulus for prolactin secretion is reduced environmental NaCl and/or osmolarity.
Acute cardiovascular autonomic responses to inhaled particulates.

Harmful effects of inhaled particulates have been established in epidemiologic studies of ambient air pollution. In particular, heart rate variability responses to high levels of environmental tobacco smoke (ETS), similar to responses observed during direct smoking, have been reported. We sought to determine whether such responses could be observed at lower particulate concentrations. We monitored cardiovascular responses of non-smoking 21 women and 19 men to work-place-relevant levels of: ETS, cooking oil fumes (Coil), wood smoke (WS), and water vapor as sham control. Responses, tested on three consecutive days (random order of aerosol presentation), were averaged for each subject. Low frequency spectral powers of heart rate and blood pressure rose during recovery from exposure to particulate, but not to sham exposures. At breathing frequencies, spectral power of men’s systolic pressure doubled, and baroreflex effectiveness increased, following ETS exposure. An index of sympathetic control of heart rate was more pronounced in men than women, in response to ETS and Coil, compared to WS and sham. When measured under controlled conditions, autonomic activities in non-smoking men and women exposed to low level, short term, particulate concentrations were similar to those observed during longer term, higher level exposures to ETS and to direct smoking. These increased indexes of sympathetic control of heart rate and peripheral vasomotion followed introduction of particulates by about 15 min. Finally, coupling of heart rate and systolic pressure indicated an increase in baroreflex activity in the response to breathing ETS that was less effective in men than women.
Synthesis of unattainable ion implantation profiles — ‘Pseudo-implantation’

Abstract Metal implantation provides a powerful tool for the formation of non-equilibrium alloy layers for a wide variety of basic and applied materials applications, but the technique is fundamentally limited in two important ways: (i) the implanted species concentration is limited by sputtering of the modified layer by the incident ion beam itself, and the sputter-limited retained dose is often disappointingly low; (ii) the thickness of the modified layer is limited by the maximum ion energy available, and for practical reasons (implanter voltage) the layer thickness is often just a few hundred angstroms. We describe here a metal-plasma-immersion-based method for synthesizing non-equilibrium alloy layers of arbitrarily high dopant concentration and of arbitrary thickness. By repetitively pulse biasing the substrate to high negative voltage while it is immersed in the metal plasma from a vacuum arc plasma gun, a layer can be synthesized that is atomically mixed into the substrate with an interface width determined by the early-time bias voltage and with a thickness determined by the overall duration of the process. The species is that of the vacuum arc cathode material, which for this purpose can be a mixture of the substrate metal and the wanted dopant metal. We have used the method to form a high concentration Ta layer on the copper rails of an electromagnetic rail gun, with total surface area treated about 3000 cm2; the Ta depth profile was flat at about 50 at.% Ta in Cu to a depth of about 1000 A.
Trade Integration and Business Cycle Comovement: Evidence from the U.S.

This article evaluates the impact of bilateral trade integration on business cycle comovements of the U.S. by distinguishing intra-industry from inter-industry trade flows. We first discuss the conditions for different impacts of trade intensity on the output correlation of two trading partners. The patterns of output correlation between two economies are associated with their economic structures and the nature of economic shocks. Regression analysis with bilateral interstate trade data further confirms the conventional wisdom that business cycles are more synchronized between economies with deeper trade linkages. Disaggregate trade data further suggest that much of the observed effect from trade arises from intra-industry trade flows. There is scant evidence to support the conjecture that inter-industry trade, which likely raises sectoral specialization, causes divergence in business cycles.
The Shadow Economy in German Regions: An Empirical Assessment

Despite the increasing number of contributions to the literature, regional variations of the shadow economy have been hardly studied. This article analyses the determinants and derives the size of the shadow economy on the district level in Germany. I find that an inferior local labour market and the burden of taxation significantly contribute to the existence of the shadow economy, while a better enforcement of tax rules and regulations has the potential to deter such activities. Districts in the affluent south of Germany experience on average smaller shadow economies.
Economics, politics, and foreigners: Populist party support in Denmark and Norway

Abstract This paper investigates the dynamics of vote intention for the Danish and Norwegian Progress Parties. It shows that support patterns for these populist parties can be explained with similar independent variables. These include national economic conditions and political events. Empirical support for the usefulness of these variables is stronger in the case of the Danish Progress party. The analysis also suggests that increases in support for both parties during the 1980s was to a significant extent driven by the increase in the number of foreigners entering these countries.
Implications of sterile neutrinos for medium/long-baseline neutrino experiments and the determination of θ 13

We revisit some of the recent neutrino observations and anomalies in the context of sterile neutrinos. Among our aims is to understand more clearly some of the analytic implications of the current global neutrino fits from short-baseline experiments. Of particular interest to us are the neutrino disappearance measurements from MINOS and the recent indications of a possibly nonvanishing angle, ${\ensuremath{\theta}}_{13}$, from T2K, MINOS and Double CHOOZ. Based on a general parametrization motivated in the presence of sterile neutrinos, the consistency of the MINOS disappearance data with additional sterile neutrinos is discussed. We also explore the implications of sterile neutrinos for the measurement of $|{U}_{\ensuremath{\mu}3}|$ in this case. We then turn our attention to the study of $|{U}_{e3}|$ extraction in electron neutrino disappearance and appearance measurements. In particular, we study the effects of some of the additional $CP$ phases that appear when there are sterile neutrinos. We observe that the existence of sterile neutrinos may induce a significant modification of the ${\ensuremath{\theta}}_{13}$ angle in neutrino appearance experiments like T2K and MINOS, over and above the ambiguities and degeneracies that are already present in three-neutrino parameter extractions. There are reactor experiments, for instance those measuring ${\ensuremath{\nu}}_{e}$ disappearance like Double CHOOZ, Daya Bay and RENO, where this modification is less significant and therefore the extracted $|{U}_{e3}|$ value when sterile neutrinos are present is close to the one that would be obtained in the three-neutrino case. Based on our study, we also conclude that the results from T2K imply a 90% C.L. lower bound on $|{U}_{e3}|$, in the ``$3+2$'' neutrino case, which is still within the sensitivity of future reactor neutrino experiments like Daya Bay, and consistent with the one-$\ensuremath{\sigma}$ range of ${sin﻿}^{2}2{\ensuremath{\theta}}_{13}$ recently reported by the Double CHOOZ experiment. Finally, we argue that for the recently determined best-fit parameters, the results in the ``$3+1$'' scenario would be very close to the medium/long-baseline results obtained in the ``$3+2$'' case analyzed in this work.
Various aspects of enantiomeric recognition of (S,S)-dimethylpyridino-18-crown-6 by several organic ammonium salts

Abstract Factors responsible for complex stability and enantiomeric recognition for the interactions of (S,S)-dimethylpyridino-18-crown-6 with several organic ammonium salts were examined using an 1H NMR technique. The results indicate that cation structures have a significant effect on enantiomeric recognition; solvents play a very important role in the stability of the complexes, and anions can compete with ligands for the ammonium cations.
The Myth of the Taj Mahal and a New Theory of its Symbolic Meaning

The Nobel Prize-winning poet Rabindranath Tagore called it a “teardrop on the cheek of time”; world-traveler Eleanor Roosevelt felt that its white marble “symbolizes the purity of real love.” Both writers shared the rather widespread romantic notion that the Taj Mahal (Fig. 1), the vast mausoleum built by the Mughal emperor Shah Jahan (1592–1666) for his wife Mumtaz Mahal (1593–1631), is a noble embodiment of unparalleled marital devotion, a monument to undying love.1 The aesthetic qualities of the tomb are popularly believed to furnish proof of its builder's intense feeling: what else but great Love could have inspired such great Beauty? In fact, this “explanation” of the tomb can be shown to be essentially a myth—a myth which ignores a great deal of evidence to the contrary, that Shah Jahan was less noble and romantically devoted than we thought, and that the Taj Mahal is not purely and simply a memorial to a beloved wife. A serious reassessment of this important monument is long overdue; and in the fol...
The emergence of biomedical anthropology and its implications for the future

Primarily during the past 15 years a distinct new area within physical anthropology has emerged, biomedical anthropology. Physical anthropologists have become heavily involved in studying problems of relevance to the health and illness patterns of living humans. There has been a proportionate increase in biomedically focused papers published in the American Journal of Physical Anthropology, in biomedically focused papers presented at annual meetings of the American Association of Physical Anthropologists, and in physical anthropology doctoral dissertations oriented toward modern biomedical phenomena. Proportionately more physical anthropologists are now employed in medical schools and there has been recent growth in the proportion of physical anthropologists in anthropology departments who claim some aspect of biomedical anthropology as a research interest. Increasingly, physical anthropologists are focusing their research on cardiovascular disease, the leading cause of death in America. These distinct trends are partially a result of the nature of physical anthropology and its unique biocultural perspective. However the growth of applied anthropology, the present academic marketplace, and the availability of research funds are probably also contributing factors. The emergency of biomedical anthropology holds promise for the future of physical anthropology and for its current employment crisis. Careers with academic and nonacademic organizations engaged in biomedical research appear to be a viable alternative to careers in departments of anthropology, for biomedical anthropologists. This will entail some reorientation of graduate training for physical anthropologists. More emphasis will have to be placed on substantive biomedical subjects, research methods, and data management and analysis.
An improved formulation for the maximum coverage patrol routing problem

Abstract We present an improved formulation for the maximum coverage patrol routing problem (MCPRP). The main goal of the patrol routing problem is to maximize the coverage of critical highway stretches while ensuring the feasibility of routes and considering the availability of resources. By investigating the structural properties of the optimal solution, we formulate a new, improved mixed integer program that can solve real life instances to optimality within seconds, where methods proposed in prior literature fail to find a provably optimal solution within an hour. The improved formulation provides enhanced highway coverage for both randomly generated and real life instances. We show an average increase in coverage of nearly 20% for the randomly generated instances provided in the literature, with a best case increase over 46%. Similarly, for the real life instances, we close the optimality gap within seconds and demonstrate an additional coverage of over 13% in the best case. The improved formulation also allows for testing a number of real life scenarios related to multi-start routes, delayed starts at the beginning of the shifts, and taking a planned break during the shift. Being able to solve these scenarios in short durations help decision and policy makers to better evaluate resource allocation options while serving public.
The pseudopapilledema of neonatal-onset multisystem inflammatory disease.

Purpose To report a rare case of neonatal-onset multisystem inflammatory disease with serial photographs to characterize the optic nerve findings. Design Observational case report. Methods A 6-year-old girl with neonatal-onset multisystem inflammatory disease, who had received systemic corticosteroid therapy for 5 years, had bilateral fibrillar opacities that surrounded the optic disks and extended into the peripapillary nerve fiber layer and vessels. A magnetic resonance imaging examination and lumbar puncture revealed elevated intracranial pressure. Results The elevated intracranial pressure returned to normal following a corticosteroid taper. Optic disk photographs, taken 4 years earlier, were subsequently obtained. The optic disk appearance had remained unchanged over the 4-year period, consistent with a pseudopapilledema. Conclusion The optic disk appearance is not consistent with papilledema from increased intracranial pressure. The optic disk findings, in conjunction with the underlying inflammatory syndrome, suggest an infiltrative etiology for the atypical optic nerve findings in neonatal-onset multisystem inflammatory disease.
The design and synthesis of novel dinucleating macrocycles derived from cyclam

Abstract The preparation of two new polypyrazole ligands based on the cyclam macrocycle is described. The molecules each contain four pyrazole and four aliphatic nitrogen donor atoms and are capable of simultaneously binding to two metal ions in an unsymmetrical dinucleating fashion.
Consistent chromosomal losses in head and neck squamous cell carcinoma cell lines

Clonal chromosomal abnormalities were characterized in nine cell lines established from squamous cell carcinomas of the head and neck. Aneuploidy was a common feature; one cell line was near-diploid, three were near-triploid, four were near-tetraploid, and one cell line showed extensive variation in chromosome numbers. Consistent numerical abnormalities included loss of the sex chromosomes in six cell lines, losses of chromosomes 2 and 21 in six and five cell lines, respectively, and gain of chromosome 20 in five cell lines. Recurrent structural rearrangements included del(10)(q22-q26) (seven cell lines), i(5)(p10) (six cell lines), i(8)(q10) (six cell lines), add(19)(q13) (six cell lines), del(4)(q21-q31.3) (five cell lines), i(3)(q10) (four cell lines), del(12)(p11.1-p12) (four cell lines), and add (18)(q21-q23) (four cell lines). Other changes were noted in lower frequencies. Loss of specific regions on chromosomes 2, 3p, 4q, 5q, 8p, 10q, 12p, 18q, 19q, and 21 suggests that they may represent sites of putative tumor suppressor genes, loss of which may play a role in the pathogenesis of squamous cell carcinomas of the head and neck. Alternatively, gain of chromosomal region 3q, 5p, and 8q due to isochromosome formation suggests that more than one mechanism is involved in malignant transformation. Cytogenetic evidence of gene amplification was found in two cell lines; as an hsr(11)(q 13) in one and as dmins in the other. The clonal karyotypes of four cell lines were compared with those of their respective primary tumors. In all cell lines, clonal evolution had occurred, with loss of some rearrangements present in the primary tumors or the gain of additional abnormalities.
Managing quality uncertainty through contingency pricing

We analyze quality-contingent prices as a mechanism for mitigating the effects of quality uncertainly in e-commerce and IT goods services. A contingency pricing contract specifies a sequence of possible quality levels and corresponding prices. When the public performance probabilities differ from the firm's private (and true) probabilities, contingency pricing can expand market size and the likelihood of market existence. When the market underestimates the firm's ability to deliver quality, contingent price contracts are strictly optimal and increase the fraction of buyers. The optimal pricing scheme has a full-price rebate for mis-performance. These results have actionable value in IT-intensive contexts such as electronic retailing, application service providers, telecommunications services, business exchanges, and on line financial trading services where the information infrastructure allows easy capture, quantification, verifiability and dissemination of quality and performance information.
Triethylcholine inhibition of phosphatidylcholine synthesis in synaptosomes and mouse leukemic cells L1210 and accelerated synaptosomal uptake of choline and triethylcholine in the presence of acetylcholine.

Abstract Triethycholine and choline were incorporated into lipid fractions of L1210 mouse leukemic cells or isolated guinea pig cerebral cortex synaptosomes. Chromatography revealed that the incorporations were between 50 and 70 per cent into phosphatidyl triethylcholine or phosphatidylcholine respectively. Triethylcholine was a potent inhibitor of choline incorporation into lipid in either the L1210 cells or synaptosomes, while choline severely inhibited triethylcholine incorporation. Acetylcholine in the presence of 10 −5 M eserine increased synaptosome lipid incorporation of choline 170 per cent and triethylcholine 200 per cent. It is suggested that the lipid choline of synaptosomes represents a storage pool of choline for acetylcholine synthesis.
Alanine Scanning Mutagenesis of Aβ(1-40) Amyloid Fibril Stability

We describe here an alanine scanning mutational analysis of the Aβ(1-40) amyloid fibril monitored by fibril elongation thermodynamics derived from critical concentration values for fibril growth. Alanine replacement of most residues in the amyloid core region, residues 15–36, leads to destabilization of the elongation step, compared to wild-type, by about 1 kcal/mol, consistent with a major role for hydrophobic packing in Aβ(1-40) fibril assembly. Where comparisons are possible, the destabilizing effects of Ala replacements are generally in very good agreement with the effects of Ala replacements of the same amino acid residues in an element of parallel β-sheet in the small, globular protein Gβ1. We utilize these Ala-WT ΔΔG values to filter previously described Pro-WT ΔΔG values, creating Pro-Ala ΔΔG values that specifically assess the sensitivity of a sequence position, in the structural context of the Aβ fibril, to replacement by proline. The results provide a conservative view of the energetics of Aβ(1-40) fibril structure, indicating that positions 18–21, 25–26, and 32–33 within amyloid structure are particularly sensitive to the main-chain disrupting effects of Pro replacements. In contrast, residues 14–17, 22, 24, 27–31, and 34–39 are relatively insensitive to Pro replacements; most N-terminal residues were not tested. The results are discussed in terms of amyloid fibril structure and folding energetics, in particular focusing on how the data compare to those from other structural studies of Aβ(1-40) amyloid fibrils grown in phosphate-buffered saline at 37 °C under unstirred (“quiescent”) conditions.
Valiron's theorem in the unit ball and spectra of composition operators

Abstract We prove a version of Valiron's conjugacy theorem for Schur class mappings of the unit ball of C N . As an application we obtain a formula for the spectral radius of composition operators on the ball with Schur class symbols.
Large deviations for trajectories of sums of independent random variables

Given a sequence of independent, but not necessarily identically distributed random variables,Yi, letSk denote thekth partial sum. Define a function\(\tilde S:[0,\infty ) \to \mathbb{R}\) by taking\(\tilde S(t)\) to be the piecewise linear interpolant of the points (k, Sk), evaluated att, whereS0=0, andk=0, 1, 2,... Fort∈[0, 1], let\(\tilde S_n (t)\mathop = \limits^{def} \tilde S(nt)\). The\(\tilde S_n \) are called trajectories. With regularity and moment conditions on theYi, a large deviation principle is proved for the\(\tilde S_n \).
High-temperature creep of NaCl-KCl solid- solution alloys

Polycrystalline NaCl-KCl solid solution alloy, considering high temperature creep under constant compression stress
Learning to teach Sport Education in Russia: factors affecting model understanding and intentions to teach

While remarkably positive findings have been presented in research focusing on Sport Education in school settings, investigations on how preservice teachers learn to teach a new curriculum in physical education have been described as ‘the missing link’ in curriculum research. The purpose of this study was to introduce Sport Education to students in a Russian physical education pedagogical college, and to track their understanding of the model through a series of learning experiences. An action research methodology was employed as the main design of this study, which included four experience steps: lecturing, participating, planning and teaching. The most significant finding related to the knowledge that preservice teachers received during their intensive participation. In particular, this cohort of preservice teachers began with the misconception that Sport Education is a model where the teacher is essentially substituted by the students in terms of the operation of the class. However, by the end of the e...
Spatial and temporal properties of a tunable picosecond dye-laser oscillator-amplifier system

In this paper, we describe a high-power picosecond dye-laser system providing tunable 1.5-mJ pulses with a uniform wave front and Gaussian spatial profile. With the aid of a computer-controlled data acquisition system, we have analyzed for the first time the temporal coherence properties of such a system.
A probabilistic approach to acoustic echo clustering and suppression

This paper introduces an approach to cluster and suppress acoustic echo signals in hands-free, full-duplex speech communication systems. We employ the instantaneous recursive estimate of the magnitude squared coherence (MSC) of the echo line signal and the microphone signal, and model it with a two-component Beta mixture distribution. Since we consider the case of multiple microphone pickup, we further integrate the normalized recording vector as location feature into the proposed approach to achieve reliable soft decisions on the echo presence. The location information has been widely used for clustering-based blind source separation, and can be modeled using a Watson mixture distribution. Simulation evaluations of the proposed method show that it can achieve significant echo suppression performance.
The empathy cycle: Refinement of a nuclear concept.

Delineates a sequence of distinct stages involved in empathic interaction and describes conditions that initiate this sequence, which has 3 main interior phases: (Phase 1) empathic resonation by Person A in response to B (who is personally expressive in some way), (Phase 2) A's attempt to convey responsive understanding to B, and (Phase 3) B's actual reception/awareness of A's communication. When the process continues, Phase 1 is again the core feature, and 2 and 3 follow in cyclical mode. There is room for considerable slippage between the inner resonation, communication, and reception levels, and measures based on data from different phases would at best be moderately associated. Principal existing (state) scales are located in reference to the model, and illustrative results take on new meaning not involving contradiction.
Enzyme changes during development of holo- and hemi-metabolic insects

Abstract 1. 1. Several carbohydrate metabolizing enzymes were examined spectrophotometrically and electrophoretically in four life stages of the holometabolic fruit fly, Drosophila pseudoobscura , and in three life stages of the hemimetabolic pea aphid, Acyrthosiphon pisum . 2. 2. Drosophila pupae exhibit significantly lower enzyme activities than third instar larvae. Most enzymes recover to larval levels or higher in adults, but some continue to decrease following eclosion. 3. 3. Enzyme activities remain relatively unchanged during development of Acyrthosiphon . 4. 4. The same isozymic forms of each enzyme are usually represented in all life stages of Drosophila , and in all life stages of Acyrthosiphon . 5. 5. Enzyme levels parallel the distinct morphological and physiological changes characterizing development of representative holo- and hemi-metabolic insects.
An iterative Newton-Raphson method to solve the inverse admittivity problem

By applying electrical currents to the exterior of a body using electrodes and measuring the voltages developed on these electrodes, it is possible to reconstruct the electrical properties inside the body. This technique is known as electrical impedance tomography. The problem is nonlinear and ill conditioned meaning that a large perturbation in the electrical properties far away from the electrodes produces a small voltage change on the boundary of the body. This paper describes an iterative reconstruction algorithm that yields approximate solutions of the inverse admittivity problem in two dimensions. By performing multiple iterations, errors in the conductivity and permittivity reconstructions that result from a linearized solution to the problem are decreased. A finite-element forward-solver, which predicts voltages on the boundary of the body given knowledge of the applied current on the boundary and the electrical properties within the body, is required at each step of the reconstruction algorithm. Reconstructions generated from numerical data are presented that demonstrate the capabilities of this algorithm.
Why do so many drug users smoke

To better understand why most persons in drug treatment smoke, we explored patients' views of the relationship between their smoking, methadone, and drug use. Recruiting from four methadone clinics, we held seven focus groups with 68 current smokers, and 10 individual interviews with former smokers. Sessions were audio-taped, transcribed, and coded. Participants were > or =18 years old, smoked > or =5 cigarettes per day, and had used prescription methadone for > or =2 years. Most patients linked smoking, methadone, and drug use in three ways. First, patients said smoking and drug use were complementary. Examples included smoking to reduce methadone after taste and using drugs to reduce smoking-related throat pain. Second, smoking and drug use were similar because they shared cues and withdrawal symptoms. Third, smoking differed from drug use because it had fewer acute consequences. Because smoking, methadone, and drug use are closely interrelated, future addictions research and treatment protocols should address them in combination.
Characterization of a mediated amperometric biosensor for hypoxanthine using deflavo xanthine oxidase

Deflavo xanthine oxidase was prepared by removing the flavine adenine dinucleotide (FAD) group from the native enzyme using 2 M CaCl2. The deflavo enzyme was effectively stabilized by 5 mM EDTA in Tris buffer solution, pH 8, and retained about 80% of its activity after several days when stored in this medium at 4°C. The deflavo enzyme was then used for the development of a mediated amperometric electrode for hypoxanthine/xanthine using 1,1′-dimethylferricinium as mediator, and its performance characteristics were compared to a native enzyme electrode. The resulting deflavo xanthine oxidase electrode was not noticeably sensitive to oxygen in the presence of hypoxanthin while its capability to interact with ferricinium remained intact. The electrode sensor with immobilized deflavo enzyme showed high operational and storage stabilities with a detection limit of about 0.1 μM. No significant sensitivity loss was observed on the enzyme electrode after 150 repeated analyses during a 7.5 hour operation. The deflavo enzyme electrode retained 80% of its sensitivity when stored at 4°C after a month.
Network design arc set with variable upper bounds

In this paper we study the network design arc set with variable upper bounds. This set appears as a common substructure of many network design problems and is a relaxation of several fundamental mixed-integer sets studied earlier independently. In particular, the splittable flow arc set, the unsplittable flow arc set, the single node fixed-charge flow set, and the binary knapsack set are facial restrictions of the network design arc set with variable upper bounds. Here we describe families of strong valid inequalities that cut off all fractional extreme points of the continuous relaxation of the network design arc set with variable upper bounds. Interestingly, some of these inequalities are also new even for the aforementioned restrictions studied earlier. © 2007 Wiley Periodicals, Inc. NETWORKS, Vol. 50(1), 17–28 2007
A tension observer for nonlinear web-winding systems with air entrainment

This paper presents a tension observer for web-winding systems such as tape drives, using a nonlinear model where reel radii vary with time. The observer is unique in a certain sense, and when the spring and damping parameters of the system are known the observed tension converges exponentially to the true tension. In practice, air entertainment makes the spring and damping parameters difficult to know, and in this case the observer uses estimates. Assuming only that the unknown parameters satisfy certain bounds (but may vary in time), the maximum observer error is derived via an interesting and exactly solvable problem in variational calculus. This error depends upon the quality of the spring and damping parameter estimates. A simulation shows observer performance.
Protection mechanisms of freely suspended animal cells (CRL 8018) from fluid‐mechanical injury. Viscometric and bioreactor studies using serum, pluronic F68 and polyethylene glycol

We use bioreactor and viscometric studies to examine the mechanism by which three additives, fetal bovine serum (FBS), pluronic F68, and polyethylene glycol (PEG), protect the freely suspend CRL-8018 cells from damage due to interactions with bubbles in agitated bioreactors. In bioreactor studies, the protective effect of an addictive could be due to either changes in the ability of the cell resist shear (biological mechanism) or to changes in the medium properties that effect the level or frequency of forces experienced by the cells (physical mechanism). Bioreactor studies show that protection by all three addictives occurs whether the cells are grown in the presence of the addictives (long exposure) or the addictives are added to medium after the cells were exposed to detrimental agitation intensity (short exposure). In the viscometric studies, exposure of cells to laminar shear in the absence of gas-liquid interfaces assesses only the ability of the cells to resist a constant level of shear in a medium with or without an additive. Viscometric studies show that prolonged exposure to FBS makes the cells more shera tolerant, but that short (30-120 min) exposure to FBS does not affect their shear tolerance. We thus conclude that the protective effect of FBS in bioreactors id of both physical and biological nature. The biological contribution is metabolic in nature rather than fast acting. Viscometric studies show that either long or short exposure of the cells to either F68 or PEG does not make the cells more shear tolerant. WE therefore conclude that the protective effect of F68 and PEG does not make the cells more shear tolerant. We therefore conclude that the protective effect of F68 and PEG in bioreactors is physical in nature.
Response of flooded rice to various sources of zinc

Zinc deficiency has been one of the major micronutrient disorders of flooded rice. Several researchers have reported that Zn deficiency could be corrected by the application of various Zn fertilizers to soil (Mikkelsen & Brandon, 1975), to seedling root (Yoshida et al. 1970; Katyal & Ponnamperuma, 1975) or to plants as foliar spray. Also there has been much speculation about the most suitable form of Zn fertilizer for correcting Zn deficiency of flooded rice. A glasshouse study was conducted to compare the effectiveness of various Zn fertilizers for rice grown under flooded conditions.
Psychological Interventions in the Pre-Surgical Period

The literature on pre-surgical psychological interventions designed to improve psychological adjustment to and recovery from surgery, as well as increase cost-effectiveness, is reviewed. Three broad classifications of interventions (information-based interventions, behaviorally-oriented interventions, and insight-oriented interventions) are discussed based on previous studies aimed at demonstrating the utility of each approach. Limitations of the research in this area are presented and recommendations are made for effective implementation of pre-surgical interventions.
Parenting and Academic Achievement Intergenerational Transmission of Educational Advantage

A growing body of research has examined how cultural capital, recently broadened to include not only high-status cultural activities but also a range of different parenting practices, influences ch...
FORAMINIFERAL DENSITIES OVER FIVE YEARS IN THE INDIAN RIVER LAGOON, FLORIDA: A MODEL OF PULSATING PATCHES

Densities of 5 taxa along with 7 environmental variables were measured monthly with 4 replicates at each of 3 stations over a period of 5 years. The 720 observations of density for each taxon were analyzed by General Linear Models with density as the dependent variable. Differences among stations, years, seasons and their interactions are all significant. When treated as covariates environmental variables contributed little to explaining the observed variability in densities. However, the observed densities of the taxa are highly correlated and when a single taxon is treated as a covariate most of the variability in the density of a related taxon is explained. There are no significant differences among replicates (taken within a square meter) or their interactions. Consequently, the biotic or abiotic factor(s), although unknown, responsible for the simultaneous density variation of the taxa operate on a relatively small spatial scale. Based on these observations and previous studies, we propose a model wherein individual foraminifers are spatially distributed as a heterogeneous continuum forming patches with different densities that are only meters apart; reproduction is asynchronous causing pulsating patches that vary in space and time. Thus, we would expect significant differences among stations, years, seasons and their interaction. At the same time, no long-term increase or decrease in density for any of the taxa is observed. Evidently, long-term stability is achieved through considerable short-term variability in space and time. Although observations at a single station are not indicative of a larger area at any particular time, the concept of pulsating patches indicates that observations at a station will in the long-term give an assessment of a larger area.
Implementation of near Shannon limit error-correcting codes using reconfigurable hardware

Error correcting codes (ECCs) are widely used in digital communications. New types of ECCs have been proposed which permit error-free data transmission over noisy channels at rates which approach the Shannon capacity. For wireless communication, these new codes allow more data to be carried in the same spectrum, lower transmission power, and higher data security and compression. One new type of ECC, referred to as Turbo Codes, has received a lot of attention, but is computationally expensive to decode and difficult to realize in hardware. Low density parity check codes (LDPCs), another ECC, also provide near Shannon limit error correction ability. However, LDPCs use a decoding scheme which is much more amenable to hardware implementation. This paper first presents an overview of these coding schemes, then discusses the issues involved in building an LDPC decoder using reconfigurable hardware. It presents a hypothetical LDPC implementation using a commercial FPGA, which will give an idea of future research issues and performance gains.
System interconnections and combinatorial integer sequences

Given two nonlinear input-output systems which are analytic in the sense that they have convergent Fliess operator representations, it is known that their interconnection in almost any fashion will produce another system in this same class. Recent work has focused on characterizing the radius of convergence for a variety of such interconnections. A key observation in this analysis was that certain combinatorial integer sequences naturally appear. The first goal of this paper is to gather from the literature all the known relationships between system interconnections and such sequences and organize them in a coherent manner. In the process it becomes clear that Stirling numbers play a central role in the most nontrivial types of system interconnections, namely, cascade and feedback connections. The second goal is to describe these relationships.
Linguistic Ability in Early Life and the Neuropathology of Alzheimer's Disease and Cerebrovascular Disease: Findings from the Nun Study

Findings from the Nun Study indicate that low linguistic ability in early life has a strong association with dementia and premature death in late life. In the present study, we investigated the relationship of linguistic ability in early life to the neuropathology of Alzheimer's disease and cerebrovascular disease. The analyses were done on a subset of 74 participants in the Nun Study for whom we had handwritten autobiographies completed some time between the ages of 19 and 37 (mean = 23 years). An average of 62 years after writing the autobiographies, when the participants were 78 to 97 years old, they died and their brains were removed for our neuropathologic studies. Linguistic ability in early life was measured by the idea (proposition) density of the autobiographies, i.e., a standard measure of the content of ideas in text samples. Idea density scores from early life had strong inverse correlations with the severity of Alzheimer's disease pathology in the neocortex: Correlations between idea density scores and neurofibrillary tangle counts were -0.59 for the frontal lobe, -0.48 for the temporal lobe, and -0.49 for the parietal lobe (all p values < 0.0001). Idea density scores were unrelated to the severity of atherosclerosis of the major arteries at the base of the brain and to the presence of lacunar and large brain infarcts. Low linguistic ability in early life may reflect suboptimal neurological and cognitive development, which might increase susceptibility to the development of Alzheimer's disease pathology in late life.
The New Look in Political Ideology Research

Over 50 years of research into American political ideology have left scholars with a contested paradigm. One side argues that the mass public is distinctly nonideological. The other side argues that ideological thinking is not beyond the public. The way forward for research in political ideology does not lie in rehashing this debate but in advancing two new areas of work. The first considers the role that values and principles play in determining the political and ideological thinking of individuals. The second questions the current conception and measurement standards of political ideology. This research argues that ideology among the American mass public is formed by positions along two related but separate dimensions. In this article, we summarize the major arguments of and criticisms of current ideology research. Then we discuss recent research on principles and values and the measurement of ideology.
Measuring the Comparative Advantage of Agricultural Activities: Domestic Resource Costs and the Social Cost-Benefit Ratio

The Domestic Resource Cost (DRC) indicator is widely used in developing countries to measure comparative advantage and guide policy reforms. In this paper we demonstrate that the DRC formula is biased against activities that rely heavily on domestic factors (land and labor), and that a simple Social Cost-Benefit (SCB) ratio is a generally superior measure of social profitability. The SCB uses the same data as the DRC in a formula which does not distort profitability rankings. The policy significance of improved measurement is shown using data from Kenya, where the DRC overstates the relative profitability of activities using large amounts of tradable inputs.
Social Security privatization and older women: A feminist political economy perspective

Gender is a crucial organizing principle in society that profoundly shapes the experience of old age and aging and the distribution of resources to older women. Using a critical feminist perspective, this paper looks at privatization in the context of the state, the capital, and the sex and gender system that conjointly reproduce the dominant institutions that render women, and particularly women of color, vulnerable and dependent throughout their life courses. The substantial dependency of older women on the state and its reasons are described. The proposed privatization of Social Security is examined in terms of its gender-biased ideological underpinnings and assumptions about the nature and norms of work, productivity, individualism, interdependence, and exchange. Negative effects are particularly harsh for those older women who do not conform to the model of family status as married with male breadwinner and for those already disadvantaged by race, ethnicity, and class.