cssi/SciSciGPT-SciSciNet huggingface dataset:
Irradiated polyethylene IV — Free radical decay☆

Abstract Free radical decay was measured in linear polyethylene over the temperature range of 50° to 125°C. The radicals were formed by β- and γ-ray irradiation and their concentrations determined by e.s.r. techniques. Decay rates were measured in nitrogen, air, oxygen, and vacuum environments. The decay reaction which takes place by radical recombination can be resolved into two parts, one more rapid than the other. The rapid reaction takes place in an amorphous region or in a metastable crystalline one which is formed during irradiation; the latter region can become amorphous following a melting—solidification excursion and is, therefore, latently amorphous. The kinetics for the rapid reaction is second order, but tends toward first order as the dose and temperature are increased. The decay-rate constant values are dependent on the total radical concentration and the amount of metastable material. The slow decay reaction takes place in the crystalline region. Its rate-constant values can be related to vinyl-group decay and to the metastable material content. The effects of dose and temperature on the activation energies indicate that these energies can also be correlated with the metastable material. Variations in reaction order for the rapid decay reaction are accounted for with the aid of relationships in which the second-order decay constant is dependent on the decay time and the diffusion coefficient.
Evaluating an ambient display for the home

We present our experiences with evaluating an ambient display for the home using two different evaluation techniques: the recently proposed 'Heuristic Evaluation of Ambient Displays' and an in situ, 3-week long, Wizard of Oz evaluation. We compare the list of usability violations found in the heuristic evaluation to the set of problems that were discovered in the in situ evaluation. Overall, the 'Heuristic Evaluation of Ambient Displays' was effective - 75% of known usability problems were found by eight evaluators (39-55% were found by 3-5 evaluators). However, the most severe usability problem found in the in situ evaluation was not identified in the heuristic evaluation. Because the problem directly violated one of the heuristics, we believe that the problem is not with the heuristics, but rather that evaluators have minimal experience with ambient displays for the home.
Pathway engineering strategies for production of beneficial carotenoids in microbial hosts

Carotenoids, such as lycopene, β-carotene, zeaxanthin, canthaxanthin and astaxanthin have many benefits for human health. In addition to the functional role of carotenoids as vitamin A precursors, adequate consumption of carotenoids prevents the development of a variety of serious diseases. Biosynthesis of carotenoids is a complex process and it starts with the common isoprene precursors. Condensation of these precursors and subsequent modifications, by introducing hydroxyl- and keto-groups, leads to the generation of diversified carotenoid structures. To improve carotenoid production, metabolic engineering has been explored in bacteria, yeast, and algae. The success of the pathway engineering effort depends on the host metabolism, specific enzymes used, the enzyme expression levels, and the strategies employed. Despite the difficulty of pathway engineering for carotenoid production, great progress has been made over the past decade. We review metabolic engineering approaches used in a variety of microbial hosts for carotenoid biosynthesis. These advances will greatly expedite our efforts to bring the health benefits of carotenoids and other nutritional compounds to our diet.
Doing justice to court interpreting

With its catchy title, Doing Justice to Court Interpreting, this book is a collection of eight articles by nine authors who explore the multifaceted world of court interpreting. It was first publis...
Mechanical behavior of calcified plaques: a summary of compression and stress-relaxation experiments.

This paper summarizes the results from mechanical testing of atherosclerotic plaques performed in the Cardiovascular Mechanics Laboratory and the Laboratory for Implantable Materials at UMBC. The motivation for our work is that balloon angioplasty, stenting, and roto-ablation are mechanical processes that are designed to permanently alter the shape of an occluded arterial lumen. The mechanisms of permanent plaque deformation are not known. Therefore, to study the mechanical behavior of plaques, we performed mechanical tests on atherosclerotic lesions with different compositions and investigated differences in the materials' mechanical responses. Atherosclerotic plaque specimens were subjected to two main types of loading: multiple cyclic compression and stress-relaxation. The multiple-cycle test protocol was two fifteen-cycle loading phases that were separated by a 10–15 minute unloaded “rest” period. The compressive stress-relaxation test protocol was a series of three consecutive loadings (called phases I, II, and III). Each phase consisted of a 25% compression that was achieved in less than 1 second, a 10 minute relaxation period, and a 10 minute unloaded “rest” period between loadings. In the multiple cycle compressive loading, plaques exhibited three distinct types of behavior, which corresponded to the plaque compositions. Calcified plaques showed behaviors distinct from other plaque types and healthy vessels. In contrast to the cyclic compression results, plaque types could not be distinguished solely on the basis of stress relaxation behavior. Calcified and fibrous plaques had similar behavior, and therefore histology was used for definite identification. Calcified plaques have unique mechanical properties, and therefore interventions like angioplasty, roto-ablation, and stenting may require protocols specific for calcified lesions. The optimum protocols for calcified plaques may be quite different from plaques with other compositions. It is essential to learn more about the mechanical behavior of all plaque types to increase the success rate of occlusive atherosclerosis treatments.
Theoretical exploration of hydrogen loss from AlH3 and Al2 H6

Quantum chemistry calculations are used to explore H2 loss from AlH3 and Al2 H6 and provide insight into the hydrogen production mechanism from polyalanes, a candidate material for energy storage. We present optimized structures for AlH3, Al2H4, Al2H5, and Al2H6 and some reaction pathways for their interconversion. We have found two pathways for the reaction Al2H6 → Al2H4 + H2, which have activation barriers lower in energy than for the removal of H2 from AlH3. However, the low-energy H2 loss pathway from Al2H6 suggests that the noninteracting Al–H bonds in the transition state structure favor having bonding similar to that occurring in AlH3. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Crystal Structure of an Anti-anti-idiotype Shows it to be Self-complementary

Abstract The structure of the Fab fragment of the mouse anti-anti-idiotypic monoclonal antibody (mAb) GH1002 was solved by X-ray crystallography. mAb GH1002 was elicited with the syngeneic anti-idiotype mAb MK2-23 which mimics the determinant defined by anti-human high molecular weight-melanoma associated antigen (HMW-MAA) mAb 763.74. The Fab fragments of mAb GH1002 exist in the crystal as dimers related by crystallographic 2-fold axes. The interface between dyad-related Fab fragments is formed primarily by interaction of the hypervariable loops of one with the other. The self-interaction of Fab fragments of anti-anti- idiotypic mAb GH1002 through their combining sites is extremely tight and intricate, closely resembling that observed in structures of id-anti-id complexes, and comparable in terms of total contact area, charge com- plementarity, and number of hydrogen bonds. The self-complementarity of the antibody observed here could be coincidental and thus reflect some non-specific binding capability. It might, on the other hand, be immunologically relevant and exemplify a certain degree of evolved self complementarity characteristic of antibodies participating in idiotypic cascades.
Tardive dyskinesia in children treated with atypical antipsychotic medications.

Recent years have witnessed increased antipsychotic treatment of children despite limited long-term safety data in children. In this study, motor side effects associated with the use of antipsychotic drugs in children were examined in a sample of pediatric psychiatric patients. Child and adolescent psychiatric patients receiving antipsychotics (most were on atypicals) for 6 months or longer (n = 118) were compared with antipsychotic-naive patients (n = 80) with similar age, sex ratio, and diagnoses. Only 19% of patients on antipsychotics had ever experienced psychotic symptoms. Eleven children (9%) on antipsychotics exhibited dyskinesia, when compared with 0 in the naive group (P = 0.003, Fisher's exact test). Nine of 62 African-American children (15%) on antipsychotics exhibited dyskinesia, when compared with only 4% (2 of 52) of European-American children (P = 0.003, Fisher's exact test). Children treated with antipsychotic drugs might experience a significant risk of dyskinesia even when treated only with atypical antipsychotics. Ethnicity might also be a risk factor for dyskinesia in children. Side-effect profile of the atypical antipsychotic drugs in children may be much different than that in adults.
Can positron emission tomography (PET) or PET/Computed Tomography (CT) acquired in a nontreatment position be accurately registered to a head-and-neck radiotherapy planning CT?

Purpose To quantify the uncertainties associated with incorporating diagnostic positron emission tomography/CT (PET/CT) and PET into the radiotherapy treatment-planning process using different image registration tools, including automated and manual rigid body registration methods, as well as deformable image registration. Methods and Materials The PET/CTs and treatment-planning CTs from 12 patients were used to evaluate image registration accuracy. The PET/CTs also were used without the contemporaneously acquired CTs to evaluate the registration accuracy of stand-alone PET. Registration accuracy for relevant normal structures was quantified using an overlap index and differences in the center of mass (COM) positions. For tumor volumes, the registration accuracy was measured using COM positions only. Results Registration accuracy was better with PET/CT than with PET alone. The COM displacements ranged from 3.2 ± 0.6 mm (mean ± 95% confidence interval, for brain) to 8.4 ± 2.6 mm (spinal cord) for registration with PET/CT data, compared with 4.8 ± 1.7 mm (brain) and 9.9 ± 3.1 mm (spinal cord) with PET alone. Deformable registration improved accuracy, with minimum and maximum errors of 1.1 ± 0.8 mm (brain) and 5.4 ± 1.4 mm (mandible), respectively. Conclusions It is possible to incorporate PET and/or PET/CT acquired in diagnostic positions into the treatment-planning process through the use of advanced image registration algorithms, but precautions must be taken, particularly when delineating tumor volumes in the neck. Acquisition of PET/CT in the treatment-planning position would be the ideal method to minimize registration errors.
Optimization of Dielectric Cap Adhesion to Ultra-Low-k Dielectrics

In this work, the adhesion of CVD dielectric caps to ULK MSQ spin-on dielectric materials with k values of 2.2 and 2.0, and a ULK CVD material with a k value of 2.7 is presented. A substantial improvement in cap adhesion to both the k2.2 ULK MSQ and the k2.7 ULK CVD material is demonstrated. The improvement is obtained using a low-k CVD glue material between the ULK dielectric and the subsequent cap material and/or by optimizing the CVD cap film deposition. Four-point bend measurement of adhesion strength is used to quantify the improvement in interface adhesion. The improvement in CVD cap adhesion is demonstrated to be strongly dependent upon both the glue layer film and the cap deposition conditions. While optimization of the CVD cap materials results in adequate adhesion for the k2.2 ULK MSQ, these improvements are demonstrated not to extend to the k2.0 ULK MSQ film.
Comparative studies on adrenal iron-sulfur protein and its selenium derivatives by electron nuclear double resonance

Abstract Reduced adrenal ferredoxin from beef adrenal glands has been studied by electron nuclear double resonance (ENDOR) spectroscopy in frozen 2H2O matrices near 20°K. Five proton hyperfine couplings for observation at the g∥ position of the EPR spectrum have been found in native adrenal ferredoxin and in adrenal selenaferredoxin in which 80S has been substituted for the two labile sulfurs (S∗). These couplings are attributed to five of the eight possible inequivalent β-CH2 protons in four cysteinyl residues attached to the two irons. ENDOR indicates at least three proton couplings for observation at the g∥ position. The proton couplings are all smaller in the adrenal selena-ferredoxin compared to native adrenal ferredoxin which indicates a smaller unpaired spin density on the sulfur atoms of the cysteine residues attached to the irons in the adrenal selena-ferredoxin. This may be associated with increased covalency of the FeSe bonds relative to FeS∗ bonds. 57Fe derivatives of adrenal ferredoxin and selena-ferredoxin were also prepared and 57Fe ENDOR was observed at the g∥ and g positions of the EPR spectra. The two irons at the active site were verified to be inequivalent in both derivatives. The 57Fe parallel and perpendicular hyperfine constants were decreased for one iron (probably the Fe(III) site) and unchanged or perhaps slightly increased for the other inequivalent iron (probably the Fe(II) site) in the selena-ferredoxin compared to the ferredoxin. It seems clear that the unpaired spin density at the active site is significantly changed by selenium substitution for sulfur, although these changes do not affect the biological activity. Also the inequivalence of the two irons in adrenal ferredoxin is again demonstrated.
A Summary of Michael Ruse's Darwin and Design

Michael Ruse's Darwin and Design : Science, Philosophy, Religion explains the history and philosophical arguments of the design metaphor of evolution. It recounts the historical uses of the metaphor from Plato to twentieth-century American science. Ruse explores the criticisms of the design metaphor and ultimately concludes that it is a beneficial term. The chief contribution of Darwin and Design is that it offers a clear understanding and comparison of the argument from design and the argument to design.
Wavenumber selection and Eckhaus instability in Couette-Taylor flow

Abstract We review a number of experimental results which pertain to pattern selection in Couette-Taylor flow. They include measurements of the harmonic contents of Taylor vortices, of the location of the Eckhaus boundary, of wavenumber selection by a spatial ramp of the Reynolds number, and of the axial variation of the wavenumber in the finite system. We show that many of the results can be understood quantitatively in terms of the Ginzburg-Landau amplitude equation.
Women, Sexual Asymmetry & Catholic Teaching

Women and men are biologically and reproductively dissimilar. This sexual distinctiveness gives rise to a “sexual asymmetry” -- the fundamental reality that the potential consequences of sexual intercourse are far more immediate and serious for women than for men. Advocates of contraception and abortion have sought to cure sexual asymmetry by decoupling sex from procreation, relieving women from the consequences of sex, and thus equalizing the sexual experiences of men and women. But efforts to suppress or reject biological difference have not relieved women of the consequences of sex and the vulnerabilities of pregnancy, even as they have further relieved men. With reference to trends in sexual economics, I argue in this paper that secular feminist responses to biological difference have actually served to exacerbate sexual asymmetry. I then conclude by showing how Catholic teaching on abortion, sex, marriage -- and even contraception -- provides an authentically pro-woman cultural response.
Is Department-Based Strategic Planning more Effective than Organization-Wide Strategic Planning?: Empirical Evidence from Senior Managers

This study examines the differences in department-level and organization-wide strategic planning efforts. Although much has been written about organization-wide planning, little empirical data exist on similar efforts at the departmental level. Although some research suggests that unit-level planning may allow departments to establish more appropriate priorities or create effective solutions that then percolate up to higher levels of the organization, other studies have argued that the lack of centralized, organization-wide coordination may actually result in suboptimal planning outcomes. This study addresses this paradox by using data collected from a national mail survey and personal interviews of senior managers. It suggests that although some aspects of strategic planning are perceived similarly at both levels, differences exist in relation to perceived levels of (a) conflict and cooperation, (b) innovation and empowerment, (c) support for the planning effort, and (d) change created through strategic ...
Laser-induced desorption of H2 from Si(111) 7 × 7

Laser excitation can lead to desorption when silicon surfaces are exposed to laser pulses at a frequency above the band gap. To determine whether a thermal or a photochemical desorption mechanism is operative, this study compared experimental measurements and numerical calculations for the laser-induced desorption (LID) of H2 from Si(111)7 × 7. The surface-temperature rise on Si(111)7 × 7 produced by laser pulses from a TEM-00 Q-switched ruby laser at λ = 694 nm was calculated using temperature-dependent physical and optical parameters and a finite penetration depth. The laser-induced surface heating results were then used to calculate laser-induced thermal desorption (LITD) yields for H2 from Si(111)7 × 7. The calculated H2 LITD yields as a function of laser energy, surface temperature, and hydrogen coverage were compared with the corresponding experimental H2 LID measurements. The excellent agreement between the calculated and measured LID results indicated that a thermal desorption mechanism can describe the LID of H2 from Si(111)7 × 7. Photochemical LID was also considered as an alternative desorption mechanism. Although significant electron-hole pair densities were estimated at the silicon surface following laser excitation, an unambiguous distinction between thermal and photochemical desorption mechanisms was difficult because the optical properties of silicon vary dramatically with temperature. In addition, the surface heating calculations indicated that silicon surface melting can occur given typical experimental conditions used for LID from silicon surfaces.
Inertial microfluidics for flow cytometry

Inertial components of the Navier-Stokes equations are usually not considered in microfluidic flows but have recently been shown to be of great practical use for continuous manipulation of particles and cells. After introducing the physical basis of the counter-intuitive self focusing of particles in a single inlet flow, I will discuss our current best focusing systems, and I will present results on using inertial focusing to create an extreme throughput flow cytometer for blood analysis. This system is an imaging cytometer implementation that can image 1 million focused blood cells per second, with the capability to increase to 20 million cells per second with appropriate wide-field of view imaging systems. The microfluidic device consists of 256 parallel high-aspect ratio microchannels in each of which two streams of focused cells assemble. These cells also form regular trains in the direction of flow such that cell coincidence is a rare occurrence, far below Poisson statistics suggest. Controlled inertially focused streams of particles are poised to provide next-generation filter-less filters and simplified flow cytometry instruments which ultimately may aid in water treatment environmental cleanup and cost-effective medical diagnostics.
Racial characteristics of women undergoing surgery for pelvic organ prolapse in the United States

Objective This study was undertaken to compare the prevalence, demographics, and complications of pelvic organ prolapse surgery across races in the United States. Study Design Data from the 2003 National Census and the 2003 National Hospital Discharge Survey were used to determine rates of prolapse surgery, demographic characteristics, morbidity, and mortality across races. Results In 2003, 199,698 women underwent prolapse surgery. Rates of prolapse surgery per 10,000 women were 14.8, 5.6, and 8.7 in women of white, black, and other races. By geographic region, surgical rates per 10,000 white vs black women differed most in the West (16.0 vs 0.8). Of black women, 27% were on public assistance, compared with 5.9% and 9.6% women of white and other races. Complications occurred in 19.4%, 34.1%, and 27.4% of women of white, black, other races. Mortality was uncommon for all races Conclusion Racial disparities between white and black women undergoing prolapse surgery appear to exist.
Modeling of pulse compressors using Kostenbauder matrices

In this paper we present a method for modeling ultrashort-laser-pulse compressors/stretchers using Kostenbauder matrices. In this method, a Gaussian pulse is represented by a 2×2 complex Q-matrix and an optical element is represented by a 4×4 real K-matrix. This formalism models pulse compressors and performs full spatio-temporal analysis. Additionally, this formalism allows for uncertainty and sensitivity analyses of the compressors/stretchers. While being simple to implement numerically, this method is computationally much faster than the other equivalent approaches, such as use of Wigner matrices and Wigner functions.
Interactions of dietary fat and 2,5-anhydro-d-mannitol on energy metabolism in isolated rat hepatocytes

The fructose analog 2,5-anhydro-d-mannitol (2,5-AM) stimulates feeding in rats by reducing ATP content in the liver. These behavioral and metabolic effects occur with rats fed a high-carbohydrate/l...
Adaptation Dynamics Measures in Simultaneously Recorded Pattern Electroretinograms and Visual Evoked Responses

In this study a new methodology to measure adaptation dynamics of simultaneously recorded Pattern ElectroRetinoGrams (PERG) and Visual Evoked Potentials (PVEP) were developed. Monocular PERGs and VEPs were recorded in response to randomly delivered bursts (1 through 8) of visual reversal displays in ten adult normal subjects. Reversals were 102ms apart and reversal bursts were separated with 510ms intervals. Stimuli were horizontal gratings presented on a custom made display designed using fast onset/offset white LEDs. Responses to individual reversals were obtained by simultaneous two channel continuous recordings. Data were processed offline by selective averaging based on burst size followed by subtraction and shifting of the previous consecutive burst responses from the last consecutive burst response. The results showed that PERG (N35-P50) component showed little change (no adaptation) while (P50-N95) reduced 20% in the second reversal (adaptation <;200ms). VEP (N75P100) and (P100-N135) components, on the other hand, exhibited dramatic reduction (35%) in the first four reversals (adaptation<;500ms) before it stabilized. The methodology presented provides rapidly acquired and repeatable quantitative measures of visual adaptation dynamics for different structures of the visual pathway and may be useful in early detection of various neuroophthalmic diseases.
Regional differences in high affinity choline transport velocity in guinea-pig brain.

— The kinetic parameters of choline accumulation by synaptosomes prepared from different regions of guinea-pig brain (cortex, brainstem, and cerebellum) were determined. Choline was accumulated by a high affinity transport process for all regions tested and the apparent Michaelis constants were similar. However, the apparent maximal velocities of choline accumulation for the brain regions differed; the differences were related to the amount of acetylcholine formed by the respective regions. The results suggested that the maximal velocity of the high affinity transport process may reflect the density of cholinergic nerve endings within brain regions.
Predator stimuli and calling behavior of Carolina chickadees (Poecile carolinensis), tufted titmice (Baeolophus bicolor), and white-breasted nuthatches (Sitta carolinensis)

Evidence from different chickadee species (Poecile genus) indicates that birds can modify the note composition of their “chick-a-dee” calls in the presence of predator stimuli. Here, we tested the effects of predator models and the distance of those models on calls of three species foraging together at feeding stations: Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor), both members of the Paridae family, and white-breasted nuthatches (Sitta carolinensis), a member of the Sittidae family. Model and distance affected seed-taking rates in all three species. “Chick-a-dee” calling rates were higher in the predator context for both chickadees and titmice, but we detected no predator context effects on “quank” call rates for nuthatches. Predator and distance contexts affected acoustic parameters of notes of the “chick-a-dee” calls of chickadees and titmice; no such effects were detected for nuthatch “quank” calls. These results suggest species differences in encoding of information in the primary social calls of these three species that commonly occur in multi-species flocks. Chickadees and titmice are “nuclear” species and nuthatches are “satellite” species, and these different roles might be related to the differences in vocal signaling that we detected.
Usefulness of frataxin immunoassays for the diagnosis of Friedreich ataxia

Background Friedreich ataxia (FRDA) is a neurodegenerative disease caused by mutations in the frataxin (FXN) gene, resulting in reduced expression of the mitochondrial protein frataxin. Improved understanding of the pathophysiology of the disease has led to a growing need for informative biomarkers to assess disease progression and response to therapeutic intervention. Objective To evaluate the performance of frataxin measurements as a diagnostic tool using two different immunoassays. Methods Clinical and demographic information was provided through an ongoing longitudinal natural history study on FRDA. Frataxin protein levels from multiple cell types in controls, carriers and FRDA patients were measured and compared using a lateral flow immunoassay and a Luminex xMAP-based immunoassay. Receiver operating characteristic curve analyses were then performed to evaluate the sensitivity, specificity, and positive and negative predictive values for each immunoassay. Results For whole blood and buccal cells, analysing FRDA patients and carriers together in a cohort resulted in higher sensitivities and positive predictive values compared with analyzing controls and carriers together, with similar results between each tissue type. We then compared the usefulness of a lateral flow immunoassay with a multianalyte Luminex xMAP-based immunoassay, and showed that both assays demonstrate high positive predictive values with low rates of false negatives and false positives. Conclusions Frataxin measurements from peripheral tissues can be used to identify FRDA patients and carriers. While multiple cell types and assays may be useful for diagnostic purposes, each assay and cell type used has its advantages and disadvantages depending on study design and scope.
Low energy, variable angle electron-impact excitation of 1,3,5-hexatriene☆

Abstract A mixture of cis and trans 1,3,5-hexatriene has been studied by electron impact at incident electron energies of 20 eV, 40 eV, 50 eV, and 70 eV, at scattering angles from 0° to 80°, and with effective energy resolutions in the range from 0.05 eV to 0.15 eV. Singlet → triplet transitions with maximum intensities at 2.61 eV and 4.11 eV are observed. The lowest energy spin-allowed excitation which can be detected is the electric dipole-allowed X 1 Ag → 1 1Bu transition (in the notation appropriate for the trans isomer). No evidence has been found for a spin-allowed but symmetry-forbidden X 1 Ag → 2 1Ag excitation in the vicinity of 4.4 eV transition energy. Many other spin-allowed excitations are observed in the 6–11 eV energy-loss region, and the correlation between these features and those observed in high resolution ultraviolet absorption spectra and other electron-impact spectra is discussed.
ALTERATION IN THE RATIO OF α‐ TO β‐LACTOSE CO‐CRYSTALLIZED FROM ORGANIC SOLVENTS

Crystallization of lactose from alcohols and mixtures with dimethyl sulfoxide (DMSO) was studied. The effect of solvents, moisture, pH and temperature on the mutarotation equilibrium of lactose also was investigated. Equilibrium was attained in supersaturated alcoholic solutions in a reasonable period of time when solutions were prepared at refluxing temperatures or where acid or basic medium was present. Quantitative measurement of the anomers produced by these treatments was by GLC. The α/β ratio in the crystals obtained from the solutions in most cases approximated 3α-lactose/2βlactose which was shown by infrared spectra to be equivalent to a simple mixture of the two anomers.
Modelling Stochastic Clonal Interference

We study the competition between several advantageous mutants in an asexual population (clonal interference) as a function of the time between the appearance of the mutants ∆t, their selective advantages, and the rate of deleterious mutations. We find that the overall probability of fixation (the probability that at least one of the mutants becomes the ancestor of the entire population) does not depend on the time interval between the appearance of these mutants, and equals the probability that a genotype bearing all of these mutations reaches fixation. This result holds also in the presence of deleterious mutations, and for an arbitrary number of competing mutants. We also show that if mutations interfere, an increase in the mean number of fixation events is associated with a decrease in the expected fitness gain of the population.
Tissue-specific ontogenic expression of prostaglandin H synthase 2 in the ovine myometrium, endometrium, and placenta during late gestation and at spontaneous term labor.

Abstract Objective: The purposes of this study were to determine (1) whether uterine tissues as well as the fetal placenta are involved in the development of prostaglandin-synthesizing capacity associated with impending labor in pregnant sheep and (2) whether the key enzyme of prostaglandin synthesis, prostaglandin H synthase 2, is differentially expressed in the different intrauterine tissues during late gestation and in association with labor. Study Design: Myometrium, endometrium, and fetal placenta were removed from ewes at 95 days' gestation, (n = 3), 101 to 110 days' gestation (n = 3), 111 to 120 days' gestation (n = 3), 121 to 130 days' gestation (n = 3), 131 to 140 days' gestation (n = 3), and 141 to 145 days' gestation (n = 4) and from ewes in spontaneous term labor at 143 to 147 days' gestation (n = 4). Expressions of prostaglandin H synthase 2 messenger ribonucleic acid and protein were determined by Northern blot and Western blot analyses. Prostaglandin H synthase 2 was localized in the fetal placenta by immunohistochemical means. Results: Levels of both prostaglandin H synthase 2 messenger ribonucleic acid and protein increased gradually from 115 days' gestation in the fetal placenta and from 131 days' gestation in the endometrium. A further and more significant increase in prostaglandin H synthase 2 concentration occurred in the placenta and endometrium during spontaneous term labor. In contrast, myometrial concentrations of prostaglandin H synthase 2 messenger ribonucleic acid and protein remained at steady basal levels during the course of pregnancy and increased only during labor. Prostaglandin H synthase 2 was localized in the trophoblast cells of the fetal placenta. Conclusions: Tissue-specific ontogenic expression of prostaglandin H synthase 2 was observed in myometrium, endometrium, and placenta during late ovine gestation and spontaneous term labor. Fetal placenta and endometrium showed increased expression of prostaglandin H synthase 2 messenger ribonucleic acid and protein during late ovine gestation, whereas myometrial prostaglandin H synthase 2 concentration remained low throughout late gestation. Prostaglandin H synthase 2 concentrations in the myometrium, endometrium, and placenta are all upwardly regulated during labor. (Am J Obstet Gynecol 1999;181:1512-9.)
Extractive partition of L-aspartase and fumarase from Escherichia coli using aqueous polyethylene glycol-ammonium sulfate systems

Inorganic sulfate salts are used to form aqueous two-phase systems with polyethylene glycol (PEG) for enzyme purification. Two enzymes, L-aspartase and fumarase produced byEscherichia coli are efficiently separated into different phases in spite of the high degree of similarity in molecular weight and amino acid sequence between them. The ratio of L-aspartase to fumarase in the PEG-rich phase is more than sixty (60) times the ratio before extraction. A high degree of purification in a single extraction step can be achieved by careful selections of PEG molecular weight, pH, cation of the salts, and sodium chloride levels. Cations of sulfate-containing salts in the following order: NH 4 + >Na+>Mg2+ tend to increase the partition of L-aspartase in the PEG-rich phase. The maximal degree of enzyme purification is obtained by using PEG 4000 and ammonium sulfate as a phase system at a stable pH for both enzymes.
Attended Home Titration of Nasal Continuous Positive Airway Pressure Therapy for Obstructive Sleep Apnea

Nasal continuous positive airway pressure (CPAP) therapy for obstructive sleep apnea (OSA) is usually titrated in a sleep laboratory with full polysomnographic monitoring until apneas, nonapneic desaturation, snoring, and microarousals are eliminated. This titration is sometimes done in the second half of the diagnostic sleep study or commonly on a separate second full night in the sleep laboratory. We performed NCPAP titration in the home in 17 patients with OSA previously documented by full polysomnography. Nasal CPAP was titrated at night in the patient's home by a registered nurse or polysomnography technician monitoring real-time recordings of heart rate, thoracic impedance, oxygen saturation, and pressure at the nasal mask on a four-channel recorder (EdenTec, Eden Prairie, Minn). Recordings of the nasal CPAP titration night were reviewed later by a physician. Apneas, hypopneas, and snoring were successfully eliminated in all patients. Mean nasal CPAP pressure was 10.3 ±3.2 cm H 2 O. At the time of a follow-up interview, 13 of 17 patients continued to be compliant with nasal CPAP therapy. The mean duration of therapy was 13.4 ±11.7 months with 7.23 mean hours of use for 6.76 nights per week. This compliance compares favorably with long-term home nasal CPAP compliance previously reported in patients titrated in our sleep laboratory. Home nasal CPAP titration resulted in about a $600 savings per patient.
Initial Management of Rheumatoid Arthritis

The prognosis for the patient with newly diagnosed rheumatoid arthritis (RA) has dramatically changed over the last two decades. If a patient is diagnosed and treated early by a rheumatologist with the goal of remission or low disease activity, half of patients can expect to achieve remission while taking their disease-modifying antirheumatic drugs. This article discusses the initial therapy in early RA and reviews the studies and trials available in the literature.
Novel approaches to the determination of polychlorinated biphenyls

Abstract A modified injection port is described that can be backflushed to prevent that either the solvent is introduced into the column or that high-boiling compounds can contaminate the capillary. Computer-aided recognition of chromatographic fingerprints is applied to identify samples. The performance of the system is demonstrated by analysing technical mixtures of polychlorinated biphenyls.
Studies on the macro-molecular organization of microbial cells.

Five different methods of preparing extracts from bacterial cells yielded similar distributions of macromolecular constituents as indicated by ultracentrifugal patterns. Extracts from a number of different bacteria showed essentially similar patterns. Three principal components were found, with sedimentation constants of approximately 40, 29, and 5 S. In many extracts, it was evident that the most slowly moving peak consisted of two components, a broad diffuse boundary and a sharp spike containing desoxypentose nucleic acid. Extracts from the photosynthetic bacterium Rhodospirillum rubrum contained, in addition to the above-mentioned components, a component of very large size (sedimentation constant approximately 190 S), with which the entire pigment complement of the cells was associated. Chemical analyses of crudely fractionated extracts showed that the bulk of the pentose nucleic acid of the cells was associated with the particles of sedimentation constants from 20 to 40 S, while the desoxypentose nucleic acid was almost all present in the fraction of lower sedimentation rate.
Are patient information materials too difficult to read

This article describes a study that found much of the written patient information materials used during home visits may be too difficult for patients and caregivers to read and comprehend. A discussion of literacy and suggestions for selecting, developing, and analyzing health education and information materials that are easy-to-read and culturally appropriate are provided.
Lunar surface: Dust dynamics and regolith mechanics

[1] The lunar surface is characterized by a collisionally evolved regolith resulting from meteoroid bombardment. This lunar soil consists of highly angular particles in a broad, approximately power law size distribution, with impact-generated glasses. The regolith becomes densified and difficult to excavate when subjected to lunar quakes or, eventually, manned and unmanned activity on the surface. Solar radiation and the solar wind produce a plasma sheath near the lunar surface. Lunar grains acquire charge in this environment and can exhibit unusual behavior, including levitation and transport across the surface because of electric fields in the plasma sheath. The fine component of the lunar regolith contributes to the operational and health hazards posed to planned lunar expeditions. In this paper we discuss the mechanical response of the regolith to anticipated exploration activities and review the plasma environment near the lunar surface and the observations, models, and dynamics of charged lunar dust.
Parallel higher-order boundary integral electrostatics computation on molecular surfaces with curved triangulation

In this paper, we present a parallel higher-order boundary integral method to solve the linear Poisson-Boltzmann (PB) equation. In our method, a well-posed boundary integral formulation is used to ensure the fast convergence of Krylov subspace linear solver such as GMRES. The molecular surfaces are first discretized with flat triangles and then converted to curved triangles with the assistance of normal information at vertices. To maintain the desired accuracy, four-point Gauss-Radau quadratures are used on regular triangles and sixteen-point Gauss-Legendre quadratures together with regularization transformations are applied on singular triangles. To speed up our method, we take advantage of the embarrassingly parallel feature of boundary integral formulation, and parallelize the schemes with the message passing interface (MPI) implementation. Numerical tests show significantly improved accuracy and convergence of the proposed higher-order boundary integral Poisson-Boltzmann (HOBI-PB) solver compared with boundary integral PB solver using often-seen centroid collocation on flat triangles. The higher-order accuracy results achieved by present method are important to sensitive solvation analysis of biomolecules, particularly when accurate electrostatic surface potentials are critical in the molecular simulation. In addition, the higher-order boundary integral schemes presented here and their associated parallelization potentially can be applied to solving boundary integral equations in a general sense.
Some Puzzles and Unresolved Issues About Quantum Entanglement

Schrodinger (Proc Camb Philos Soc 31:555–563, 1935) averred that entanglement is the characteristic trait of quantum mechanics. The first part of this paper is simultaneously an exploration of Schrodinger’s claim and an investigation into the distinction between mere entanglement and genuine quantum entanglement. The typical discussion of these matters in the philosophical literature neglects the structure of the algebra of observables, implicitly assuming a tensor product structure of the simple Type I factor algebras used in ordinary Quantum Mechanics (QM). This limitation is overcome by adopting the algebraic approach to quantum physics, which allows a uniform treatment of ordinary QM, relativistic quantum field theory, and quantum statistical mechanics. The algebraic apparatus helps to distinguish several different criteria of quantum entanglement and to prove results about the relation of quantum entanglement to two additional ways of characterizing the classical versus quantum divide, viz. abelian versus non-abelian algebras of observables, and the ability versus inability to interrogate the system without disturbing it. Schrodinger’s claim is reassessed in the light of this discussion. The second part of the paper deals with the relativity-to-ambiguity threat: the entanglement of a state on a system algebra is entanglement of the state relative to a decomposition of the system algebra into subsystem algebras; a state may be entangled with respect to one decomposition but not another; hence, unless there is some principled way to choose a decomposition, entanglement is a radically ambiguous notion. The problem is illustrated in terms a Realist versus Pragmatist debate, the former claiming that the decomposition must correspond to real as opposed to virtual subsystems, while the latter claims that the real versus virtual distinction is bogus and that practical considerations can steer the choice of decomposition. This debate is applied to the fraught problem of measuring entanglement for indistinguishable particles. The paper ends with some (intentionally inflammatory) remarks about claims in the philosophical literature that entanglement undermines the separability or independence of subsystems while promoting holism.
Monte Carlo Simulations of Disjoining-Pressure Isotherms for Lennard−Jones Surfactant-Stabilized Free Thin Films

We present Monte Carlo simulations of disjoining-pressure isotherms for soluble-surfactant-stabilized free thin films. To mimic actual experiments, we define a disjoining-pressure isotherm such that films of all thicknesses on that isotherm are in equilibrium with the same infinite reservoir of surfactant and solvent. This necessitates use of inert-gas molecules to vary the film thicknesses while still maintaining equilibrium with the reservoir. All types of molecules in the system (solvent, surfactant, and inert gas) are defined by using Lennard−Jones (LJ) based potentials. For thick films, the center of the film is sufficiently far away from the interface for the surfactant orientation to be random, whereas at the interface, the surfactant molecules are elongated and oriented roughly perpendicular to the interface. As the films are thinned, the disjoining pressure (Π) is positive and increases monotonically. Two bulk surfactant concentrations are considered that differ by a factor of about 2. For the is...
Influence of laser fluence on the synthesis of carbon nitride thin films by nitrogen-ion-assisted pulsed-laser deposition

Carbon nitride films were deposited by pulsed Nd:YAG laser ablation of graphite with assistance of nitrogen ion beam bombardment. The nitrogen to carbon (N/C) atomic ratio, surface morphology and bonding state of the deposited carbon nitride films were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM). The influence of laser fluence on the synthesis of carbon nitride films was investigated. The N/C atomic ratio of the carbon nitride films can reach the maximum at the highest laser fluence. XPS and FTIR analyses indicated that the bonding state between the carbon and nitrogen in the deposited films was influenced by the laser fluence during deposition. The carbon-nitrogen bonding of C-N, C=N together with very few CequalsVN were found in the films. Results indicated that the laser fluence also had critical effect on the surface morphologies of the carbon nitride films.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Dyadic adjustment and sensation seeking compatibility

Abstract The purpose of the present study was to investigate individual differences in sensation seeking and dyadic adjustment. One hundred and two married and unmarried couples, of different ages, served as subjects. They were administered the Sensation Seeking Scale V and the Dyadic Adjustment Scale, which is designed to measure the quality of relationships. The data reveal that a disparity in sensation seeking needs among couples correlates negatively with relationship satisfaction regardless of the specific nature of their relationship (married, cohabiting or dating) and number of years they have been together. It is proposed that a match in optimal arousal motivation is an important variable that attracts partners to each other and also a major determinant of long term relationship satisfaction.
Age-related differences in the control of spatial aiming movements.

Abstract The experiment was designed to (a) examine age-related differences in the control of aiming movements, and (b) determine the locus of slowing in movement execution of older adults. Fitts's (1954) index of difficulty (ID) was used to manipulate movement execution demands, and kinematics were used to examine the response characteristics. Twelve young and 12 older adults performed simple aiming movements 10 cm or 20 cm in amplitude to targets of 0.5 cm, 1.0 cm, or 2.0 cm in width, resulting in IDs ranging from 3.32 to 6.32. The results for both young and older subjects support the prediction that movement time (MT) increases as a function of ID and that older adults are significantly slower and more affected by increases in ID than the young adults. Velocity and acceleration profiles of the older adults' movements displayed very different response characteristics than those of the young adults. The results suggest that older adults emphasize accuracy of response and are concerned with the latter pha...