cssi/SciSciGPT-SciSciNet huggingface dataset:
The use of an on-line computer to divide signals from a position-sensitive detector

Abstract The x·E-signals and the E-signals from a position-sensitive detector in the focal plane of a magnetic spectrometer were divided with the aid of a CDC 3100 computer, to cancel the appreciable energy spread in both signals when the incident particles were passing through the detector. A momentum resolution p Δp = 4200 was obtained.
Using eggshell membranes as a non-invasive tool to investigate the source of nutrients in avian eggs

Development of minimally invasive techniques to collect nutritional information from free-living birds is desirable for both ethical and conservation reasons. Here, we explore the utility of waterfowl eggshell membranes to determine the nutrient source of egg formation by using stable isotope ratios. We compared δ13C and δ15N of membranes from complete king eider (Somateria spectabilis) eggs to membranes of hatched or depredated eggs of the same clutch remaining after incubation. Despite large variation among membranes (δ13C: −26 to −14‰) we found a highly predictable relationship between δ13C of complete egg membranes and remaining (hatched or depredated) membranes from the same clutch. We did not find a consistent change in either δ13C or δ15N of eggshell membranes during incubation. We suggest that isotope ratios of membranes can be used to determine the source of exogenous nutrients for egg production in income breeders, and that membranes may offer a clutch-specific reference point for dietary nutrients (‘income endpoint’) in isotopic mixing models quantifying nutrient allocation in capital or mixed-strategy breeders.
Genesis of the Anti-Plague System: The Tsarist Period

Although the anti-plague system of the former Soviet Union developed fully during the Soviet era, its foundations were laid long before the Bolshevik Revolution of 1917. This article traces the evolution of the anti-plague measures from imposition of temporary quarantine in affected areas to the creation of the standard response system and the establishment of permanent anti-plague organizations. The purpose of this article is to demonstrate that by the end of the nineteenth century and the beginning of the twentieth century, despite numerous setbacks, the Russian imperial authorities succeeded in creating a nascent system of disease surveillance dedicated to protecting the population from especially dangerous infectious diseases such as plague.
High-Mobility Stable 4H-SiC MOSFETs Using a Thin PSG Interfacial Passivation Layer

Phosphorous from P2O5 is more effective than nitrogen for passivating the 4H-SiC/SiO2 interface. The peak value of the field-effect mobility for 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) after phosphorus passivation is approximately 80 cm2/V·s. However, P2O5 converts the SiO2 layer to phosphosilicate glass (PSG)-a polar material that introduces voltage instabilities which negate the benefits of lower interface trap density and higher mobility. We report a significant improvement in voltage stability with mobilities as high as 72 cm2/V·s for MOSFETs fabricated with a thin PSG gate layer ( ~ 10 nm) capped with a deposited oxide.
A note on time, intelligence, and Rorschach movement responses.

Once in each of the last three decades, at least one personality theorist has colnmenced on psychology's general indifference to cognition concerned with the f~~cure (Murphy, 1936; Rapaporc, 1946; Allporr, 1955). In this paper I should like to suggest that the picture is changing-that there is in progress a redefinition of intelligence to include foresight and planning. I should especially like to suggest in addition chat the Rorschach test has from its inception provided us with a crude measure of apric~tde in this area. Much of the paper will deal with cognitive attributes of individuals scoring high in Rorschach movement categories. Porteus, of course, has long used the words foresight and planning in connection with his Maze Test. But since his 1950 pronouncement chat "it is time to come out boldly for the inclusion of planning in OLI~ statement of the nature of intelligence" (p. lo), he has been echoed, intentionally or not, by workers in diverse areas. Singer and Herman, for example, suggest that "the ability to defer immediate motor response . . . with the consequent resort to . . . fantasy gives man a control of his future through imagery and planning" (1954, p. 329). Shoben has included "the capacity for foresight and the self-imposed control of behavior through the anticipation of its ouccorne" within his "basic
A review of the application of chemical decontamination technology in the United States

Abstract This review provides information on the chemical decontamination of nuclear power plants. An overview of the current status of the technology is given, including a brief description of commercially-available processes. BWR recirculation piping and PWR steam generator decontaminations are described, with a comparison of the two types of operation. Corrosion data, methods of reducing recontamination rates, and waste issues are discussed. Future developments, including full-system decontaminations, are reviewed.
Speech-like vocalizations in infancy: an evaluation of potential risk factors*

This work reports longitudinal evaluation of the speech-like vocal development of infants born at risk due to prematurity or low socio-economic status (SES) and infants not subject to such risk. Twenty infants were preterm (10 of low SES) and 33 were full term (16 of low SES), and all were studied from 0;4 through 1;6. The study provides the indication that at-risk infants are not generally delayed in the ability to produce well-formed speech-like sounds as indicated in tape-recorded vocal samples. At the same time, premature infants show a tendency to produce well-formed syllables less consistently than full terms after the point at which parents and laboratory personnel note the onset of the canonical babbling stage (the point after which well-formed syllables are well established in the infant vocal repertoires). Further, even though low SES infants produce well-formed speech-like structures on schedule, they show a reliably lower tendency to vocalize in general, as reflected by fewer utterances per minute in recorded samples.
Green's-function self-energies in the two-dimensional Holstein model.

We examine the behavior of the electron and phonon self-energies obtained from quantum Monte Carlo simulations of the two-dimensional Holstein model as a function of Matsubara frequency and momentum. For the half-filled system, there is a finite-temperature phase transition to an insulating charge-density-wave state, and the electron self-energy develops a distinctive divergence. The renormalized phonon frequency softens strongly with temperature at the commensurate wave vector. Away from half-filling, the electron self-energy behaves in a manner consistent with that of a Fermi liquid.
An improved batchwise chromatographic procedure for creatine phosphokinase (CPK) isoenzyme separation.

Abstract A batchwise column chromatographic procedure for the determination of CPK isoenzymes has been developed based on the experience of column chromatography by linear salt gradient. Various steps involved in this procedure have also been shown to improve the speed, simplicity, and sensitivity of the test: (i) Serum samples should be diluted 20-fold with the equilibration buffer just prior to sample loading in order to minimize serum salt effect on recovery of isoenzyme and to allow application of a large aliquot of serum to increase test sensitivity. (ii) We have determined which fraction of eluate contained the majority of the MB or BB isoenzyme, and only that fraction of eluate should be collected for enzyme assay. (iii) We have modified the enzyme assay system allowing use of a much larger aliquot of eluate thus improving the test sensitivity. (iv) By using 3-ml disposable JELCO syringes and cellex D for column preparation the procedure becomes simplified for routine clinical use.
Positional isomers of monoene and diene fatty acids of human skin epidermal cells.

Abstract Trypsin-released epidermal cells from human skin were incubated in a tissue culture medium containing acetate-1- 14 C, and their lipids subsequently extracted and converted to methyl esters. The patterns of positional isomers present in the principal even-carbon monoenoic acids, and in octadecadienoic acid were examined after oxidative cleavage of individual esters, and GLC of the fragments. In the case of the C 18 species, the radioactivity of the fragments was assayed. It was found that Δ9 acids predominated, and that cleavage products of 18: Δ9,12 contained radioactivity. Thus epidermal cells apparently have the ability to synthesize linoleic acid.
Techniques of modeling spatial phenomena of background radiation in terrain geometric cluttering

This study is focused on electro-optical imaging techniques and analysis that support warning receiver systems in detecting threats. These systems were enabled to receive threat signals, which are generalized to be additive in nature (signal + noise) [1]. The sources of the noise were identified as man-made noise. This, include the humming of the system's power supply in a radio receiver, feedback oscillation noise, or ignition radiation, including terrain noise that affects global positioning systems (GPS) noise angle. However, this study is restricted to random noise signals that composite terrain phenomena. A model of modules (M2) was use to evaluate a characteristic of microwave communication signals, clutter. This noise phenomenon of radiation in the radio frequency has gained attention in communication marketing and advertising. The results of the evaluation show that terrain geometric cluttering can significantly affect the distribution of this marketable radio frequency. This consideration could be applied to improve future regional and urban planning using radiophysical orientation for subdivision development.
Lock-in and the Costs of Switching Mainframe Computer Vendors: What Do Buyers See?

This paper closely studies the historical experiences of computer users faced with incompatibility problems. One key point throughout the discussion is that operating system compatibilities and application software were the principal source of switching costs. The larger point here is that vendor specificity is partially a choice-variable for the buyer. It influences many facets of an organization, as well as management and employee behavior. Foresighted users anticipate that daily decisions regarding programming practices and equipment maintenance influence the costs of switching during a later vendor decision. Buyers take a wide variety of actions, both simple and complex. Most of the paper is concerned with documenting and analyzing how buyers change investments, collect information, manipulate bidding procedures and change managements practices--either in anticipation of, or in response to, incompatibility problems. Copyright 1997 by Oxford University Press.
Biotransformation of 2,4,6-trinitrotoluene (TNT) by enchytraeids (Enchytraeus albidus) in vivo and in vitro

2,4,6-Trinitrotoluene (TNT) is toxic to soil invertebrates, but little is known about its toxicokinetic behavior in soil. Tissue residue analysis was used to evaluate whether the presence of TNT and its reduced metabolites in soil invertebrates was due to uptake of these compounds from the soil into the organism, or due to microbial transformation of TNT associated with the organism followed by uptake. Adult white potworms (Enchytraeus albidus) were exposed to non-lethal concentrations of TNT in amended artificial soil for 21 d, or to TNT in solution for 20 h. Soil exposure studies confirmed earlier reports that TNT was transformed in enchytraeids in vivo to 2- and 4-aminodinitrotoluenes. However, enchytraeid exposure to TNT in solution led to the additional presence of 2,4-diaminonitrotoluene as well as 2- and 4- hydroxyamino-dinitrotoluenes and azoxy-compounds, suggesting that TNT can be metabolized in vivo in the absence of soil. Incubation of unexposed enchytraeid homogenates with TNT led to a protein-dependent appearance of these metabolites in vitro after > or =16 h incubation. Cellular fractionation studies indicated that most of this activity resided in the 8000 x g pellet, and was completely inhibited by broad-spectrum antibiotics. These studies demonstrate that enchytraeids can transform TNT in vivo and in vitro, at least in part, by bacteria associated with the host organism.
Heavy-Ion Elemental Abundances in Large Solar Energetic Particle Events and Their Implications for the Seed Population

We have surveyed the ~0.1–10 MeV nucleon to the -1 abundances of heavy ions from 3He through Fe in 64 large solar energetic particle (LSEP) events observed on board the Advanced Composition Explorer from 1997 November through 2005 January. Our main results are (1) the 0.5–2.0 MeV nucleon to the -1 3He/ 4He ratio is enhanced between factors of ~2–150 over the solar wind value in 29 (~46%) events. (2) The Fe/O ratio in most LSEP events decreases with increasing energy up to ~60 MeV nucleon to the -1. (3) The Fe/O ratio is independent of CME speed, flare longitude, event size, the 3He/4He ratio, the pre-event Fe/O ratio, and solar activity. (4) The LSEP abundances exhibit unsystematic behavior as a function of M/Q ratio when compared with average solar wind values. (5) The survey-averaged abundances are enhanced with increasing M/Q ratio when compared with quiet coronal values and with average gradual SEP abundances obtained at 5–12 MeV nucleon to the -1. (6) The event-to-event variations in LSEP events are remarkably similar to those seen in CME-driven IP shocks and in 3He-rich SEP events. The above results cannot be explained by simply invoking the current paradigm for large gradual SEP events, i.e., that CME-driven shocks accelerate a seed population dominated by ambient coronal or solar wind ions. Instead, we suggest that the systematic M/Q-dependent enhancements in LSEP events are an inherent property of a highly variable suprathermal seed population, most of which is accelerated by mechanisms that produce heavy-ion abundances similar to those observed in impulsive SEP events. This heavy-ion-enriched material is subsequently accelerated at CME-driven shocks near the Sun by processes in which ions with higher M/Q ratios are accelerated less efficiently, thus causing the Fe/O ratios to decrease with increasing energy.
In-situ Fiberoptic Thermometry Measurements of Wafer Temperature During Plasma Etching Using an Electron Cyclotron Resonance Source

The increase in wafer temperature due to plasma heating during etching has been studied. Si and InP were etched using a high ion density discharge generated by an electron cyclotron resonance source. The wafer temperature was measured in-situ using fiberoptic thermometry as microwave power, rf power, chamber pressure, and gas flow were varied. Wafer temperatures increased with both microwave and rf power, and decreased with chamber pressure. For rf power of 50 W, chamber pressure of 1 mTorr, a source distance of 13 cm, and 10 sccm Ar flow, an increase in microwave power from 50 to 500 W caused the temperature to increase from 62 to 186 °C. Additionally, the use of He flowing at the backside of the wafer for temperature control was analyzed. By setting the backside He pressure at 3 Torr, the temperature increased from 20 °C at the beginning of the etch to only 29 °C after 12 min. Time dependent etch characteristics of InP were studied and related to the wafer temperature measurements. At 100 W microwave power, the InP etch rate increased from 100 to 400 nm/min as the wafer temperature rose from 20 to 150 °C. As the temperature increased above 150 °C, the profile became more undercut and the surface morphology improved. By setting the stage temperature to -100 °C and using 3 Torr He pressure at the backside of the wafer, the InP etch rate remained constant during etching and undercutting was suppressed. For 500 W microwave power, a fast InP etch rate of 2 μm/min was obtained when the wafer temperature was 150 °C.
Salt effect on heat-induced physical and chemical changes of salmon fillet (O. gorbuscha)

This research studied the effect of salt on kinetics for quality changes in pink salmon fillet, during commercial sterilisation. Sample cuts from salmon fillets were placed in sealed aluminum containers and heated at 121.1 °C for 10, 30 and 60 min. Samples with 1.5% (w/w) salt addition were compared with those without added salt. Salt addition reduced cook loss, area shrinkage and shear force of the heated fillet and resulted in a slightly darker colour. Effect of salt addition in thiamin loss, degree of lipid oxidation and fatty acid profile was not significant. Peroxide (PV) and thiobarbituric acid (TBA) values slightly increased within the first 10 min of heating, followed by a significant reduction as heating progressed. No measurable loss of polyunsaturated fatty acids (PUFA) was observed. Thermally processed shelf-stable salmon investigated should be a valuable source of ω-3 PUFA, with EPA values ranging from 52 to 71 mg/100 g product and DHA ranging from 258 to 340 mg/100 g of product.
Demonstration of systematic improvements in the application of the variational method to anharmonic oscillator potentials

Three sets of trial wave functions were applied to calculate the ground state and first excited state energies of the x 4 and x 6 anharmonic oscillator potentials. We demonstrate that, even with a rather crude initial guess, results can be improved by proper adjustment of the trial wave functions after careful study of their general features. Meanwhile, we found some interesting and unexpected results when applying the second set of trial wave functions. Once again, we suggest using together with computer algebra software packages, these examples when teaching the variational method in a quantum mechanics course.
How do side chains orient globally in protein structures

An angle Ω is defined to serve as a metric for global side-chain orientations, which reflects the orientation of the side chain relative to the radial vector from the center of the protein to an amino acid. The side-chain orientations of buried residues exhibit characteristically different orientations than do exposed residues, in both monomeric and dimeric structures. Overall, buried side chains point mostly inward, whereas surface side chains tend to point outward from the surface. This difference in behavior also correlates well with the residue hydrophobicity; so a global side-chain orientation can be viewed as a direct structural manifestation of hydrophobicity. When various solvent-accessible layers are considered, the behavior is relatively continuous between centrally located and exposed residues. In the case of interfacial residues between subunits, there are statistically significant differences between exposed residues and interface residues for ALA, ARG, ASN, ASP, GLU, HIS, LYS, THR, VAL, MET, PRO, and overall the interface residues have an increased tendency to point inward. Presumably, these substantial differences in orientations of side chains may be a manifestation of hydrophobic forces.
Modeling uncertainties in advanced technologies: Application to a coal gasification system with hot-gas cleanup

Uncertainties in the performance, emissions, and cost of advanced process technologies in early stages of development pose a challenge to process evaluation. Failure to account properly for uncertainties may result in misleading estimates that are then used for making decisions about technology selection and research planning. A new stochastic modeling capability has been developed for the ASPEN chemical process simulator that allows uncertainties in any process technology to be represented using probability distributions. This capability is briefly described. A detailed case study of an advanced integrated coal gasification combined cycle (IGCC) system is presented to illustrate the application of this capability. The case study involves identification and characterization of uncertainties in model inputs, propagation of uncertainties through the model, and interpretation of model results. The value of stochastic modeling is in the ability to evaluate the simultaneous effect of multiple uncertainties in a process technology and to develop more realistic estimates of process performance and cost than would otherwise be obtained from deterministic (point-estimate) analysis.
Convergence of local atomistic stress based on periodic lattice

Abstract Local stress in an atomic system, which provides an average stress measurement within a spatial volume containing a collection of atoms, is essential for determining the mechanical properties of a nanoscale structure as well as developing a proper multiscale modeling technique. Theoretically, the smaller averaging volume where a local stress can converge, the closer this atomistic stress definition can approach the ideal continuum stress. As a result, the more accurate stress concentration can be evaluated for the inhomogeneous case. With reference to the previous studies focusing on the spherical averaging volume, dependent on the type of crystals, the convergent radius of the virial stress or Hardy stress usually spans the size of several lattice constants. In this paper, we find that, once the averaging volume is periodic, the convergence of the virial stress and Hardy stress can be accomplished within one single lattice, which is much smaller than what is required by other non-periodic volumes such as a sphere. In the final section, a cracked sodium chloride crystal is considered to demonstrate that the crack opening stress described by the periodic lattices captures the stress concentration near the crack tip.
Meeting report for molecular psychiatry, 2005

The 2005 Molecular Psychiatry Meeting was held from 6 to 8 February 2005 at the Treasure Mountain Inn in Park City, Utah.
Disease outcome in patients with low stage renal cell carcinoma treated with nephron sparing or radical surgery

AbstractPurpose: We investigated the outcome of nephron sparing surgery in patients with low grade and low stage (Robson stage II or less) renal cell carcinoma.Materials and Methods: We retrospectively reviewed the records of 185 patients treated with nephron sparing surgery and 209 matched for patient age and sex, and tumor stage and grade who were treated with radical nephrectomy. Kaplan-Meier survival curves were constructed for progression and survival end points. Multivariate analysis was performed to determine the tumor characteristics independently correlated with progression and cancer death.Results: No significant difference was observed with respect to progression-free, crude or cancer specific survival between the nephron sparing surgery and radical nephrectomy groups. Less than 5% of the patients treated with conservative nephron sparing surgery had local recurrence. Tumor size was a strong independent predictor of outcome, whereas Robson stage was not. Patients treated with radical nephrectom...
Levels of immunoreactive dynorphin in brain and pituitary of hyperthyroid and hypothyroid rats

Dynorphin is a potent opioid peptide. Using a highly sensitive radioimmunoassay we have measured the levels of immunoreactive (ir) dynorphin in the cortex, hypothalamus, anterior and posterior pituitary in hyperthyroid and hypothyroid rats. Ir dynorphin levels were increased in the cortex of hypothyroid animals and decreased in the hypothalamus of hyperthyroid rats.
Regulation of NaCl transport: relation to chloride conductance.

Abstract Preconditioning of frogs in high salinity environment produced a suppression of skin Cl − conductance as well as active Na + transport. The Cl − transport effect is not readily explained by alteration in the known humoral substances vasopressin and aldosterone and could reflect a heretofore undescribed mechanism of NaCl transport regulation. A spontaneous time-dependent decrease in Cl − conductance occurred in isolated skin of unconditioned animals, possibly from inactivation or loss of an endogenous factor(s) which increases Cl − conductance. This spontaneous decrease was inhibited for two successive 0.5-h periods by plasma from non-conditioned animals placed in the inside chamber. The decrease was prevented only in the second 0.5-h period by addition of plasma from animals conditioned to high salinity. The spontaneous decrease in Cl − permeability in isolated skin and reversal by frog plasma are compatible with the presence of a humoral substance which regulates Cl − conductance.
Pharmacology of Cinoxacin in Humans

Cinoxacin was almost completely absorbed when given orally and was found to be approximately 60 to 70% protein bound. Peak serum concentrations were reached within 2 h, and detectable serum concentrations persisted up to 12 h after administration of 0.25-, 0.5-, and 1-g multiple oral doses. Although food delayed the absorption and caused a 30% reduction in mean peak serum concentrations, the overall 24-h urinary recovery was not significantly altered. Approximately 50 to 55% of the drug was excreted in the urine as unchanged drug. At 12 h, urine concentrations were still above the minimal inhibitory concentration for most common gram-negative urinary pathogens. Cinoxacin was well tolerated when administered to 23 volunteers from 10 to 28 days. Resistance among fecal isolates initially susceptible to cinoxacin was not observed in nine volunteers who were administered 0.5 g every 12 h for 4 to 28 days.
Understanding Family Roles and Ethics in Working with First-Generation College Students and Their Families.

This article examines the family roles and ethics of first-generation college students and their families through discussion of a case vignette. London's family roles applied to first-generation college students are discussed. Narrative therapy practices and an ethical model that examines the value process of counselors are explored as possible solutions.
An overview of conservative treatment options for diabetic Charcot foot neuroarthropathy

Conservative management of Charcot foot neuroarthropathy remains efficacious for certain clinical scenarios. Treatment of the patient should take into account the stage of the Charcot neuroarthopathy, site(s) of involvement, presence or absence of ulceration, presence or absence of infection, overall medical status, and level of compliance. The authors present an overview of evidence-based non-operative treatment for diabetic Charcot neuroarthropathy with an emphasis on the most recent developments in therapy.
Bone Morphogenetic Protein for Pseudarthrosis Repair in Revision Cervical Spine Surgery

Recombinant human bone morphogenetic proteins (rhBMPs) are potent osteoinductive factors that are being considered as bone graft alternatives. Well-performed prospective clinical studies have demonstrated the efficacy of such products for defined indications. This technology may be appropriate for challenging fusion scenarios, such as revision cervical spine surgery. There are recent reports of rhBMPs being used for primary anterior cervical spine surgery and rhBMPs have been demonstrated to overcome posterolateral lumbar pseudarthroses in animal models. Recently, complications have been reported with the off-label use of rhBMPs in anterior cervical spine surgery. In considering rhBMP for revision cervical surgery, the appropriate dose, carrier, and surgical techniques should be further defined and optimized.
T-independent type II immune responses generate memory B cells

Unlike T-dependent immune responses against protein antigens, T-independent responses against polysaccharides confer long-lasting humoral immunity in the absence of recall responses and are not known to generate memory B cells. Here we report that polysaccharide antigens elicit memory B cells that are phenotypically distinct from those elicited by protein antigens. Furthermore, memory B cell responses against polysaccharides are regulated by antigen-specific immunoglobulin G antibodies. As the generation and regulation of immunologic memory is central to vaccination, our findings help explain the mode of action of the few existing polysaccharide vaccines and provide a rationale for a wider application of polysaccharide-based strategies in vaccination.
Two Cultures, One Epidemic

HIV infection is a global epidemic, and health care providers involved in HIV/AIDS care must be aware of how communities with different cultures, values, beliefs, and resources are coping. This article describes a 3-month volunteer experience with the Shona people of Zimbabwe, Africa. Similarities and uniqueness between an urban setting in an industrial country and a rural environment in a developing country are explored.
Are physicians aware of which of their patients have indwelling urinary catheters

Abstract PURPOSE: Although infections associated with indwelling urinary catheters are common, costly, and morbid, the use of these catheters is unnecessary in more than one-third of patients. We sought to assess whether attending physicians, medical residents, and medical students are aware if their hospitalized patients have an indwelling urinary catheter, and whether physician awareness is associated with appropriate use of these catheters. METHODS: The physicians and medical students responsible for patients admitted to the medical services at four university-affiliated hospitals were given a list of the patients on their service. For each patient, the provider was asked: "As of yesterday afternoon, did this patient have an indwelling urethral catheter?" Respondents' answers were compared with the results of examining the patient. RESULTS: Among 288 physicians and students on 56 medical teams, 256 (89%) completed the survey. Of 469 patients, 117 (25%) had an indwelling catheter. There were a total of 319 provider-patient observations among these 117 patients. Overall, providers were unaware of catheterization for 88 (28%) of the 319 provider-patient observations. Unawareness rates by level of training were 21% for students, 22% for interns, 27% for residents, and 38% for attending physicians ( P = 0.06). Catheter use was inappropriate in 36 (31%) of the 117 patients with a catheter. Providers were unaware of catheter use for 44 (41%) of the 108 provider-patient observations of patients who were inappropriately catheterized. Catheterization was more likely to be appropriate if respondents were aware of the catheter (odds ratio=3.7; 95% confidence interval, 2.1 to 6.7, P CONCLUSION: Physicians are commonly unaware that their patients have an indwelling urinary catheter. Inappropriate catheters are more often "forgotten" than appropriate ones. System-wide interventions aimed at discontinuing unnecessary catheterization seem warranted.
Approximate invariants and Lagrangians for autonomous, weakly non-linear systems—II. Linear friction

In a previous paper, a procedure was given for the calculation of approximate, time-independent invariants for autonomous, weakly-non-linear systems with one degree of freedom, based on an expansion in linear and non-linear parameters. Such an invariant generates an approximate, time-independent Lagrangian and Hamiltonian describing the system. An extension of this procedure is given here for non-linear systems with dominant linear friction (or anti-friction). For the damped harmonic oscillator, this method yields an exact invariant, as well as a Lagrangian and Hamiltonian, in simple closed forms. In damped (anti-damped), non-linear systems, a series solution for an invariant (and Lagrangian and Hamiltonian) can be obtained by quadratures. This latter treatment is applied to the damped Duffing and van der Pol equations.
Calcium homeostasis in pregnant rats treated with ethylene glycol monomethyl ether (EGME)

Abstract The industrial solvent ethylene glycol monomethyl ether (EGME) is a known teratogen that has been reported to alter calcium metabolism in guinea pigs during chronic exposure. Because of the tremendous demand of reproduction on maternal calcium stores, the effects of EGME on calcium and vitamin D metabolism during gestation were examined. Timed pregnant rats were treated by gavage with 0, 50, or 100 mg/kg EGME in 10 ml/kg distilled water on Days 9–15 of gestation (sperm = Day 1) and examined on Days 16 and 21. Virgin rats were treated for 7 days with 0 or 100 mg/kg EGME and examined 5 days later. EGME exposure did not affect body or kidney weight in virgin or pregnant rats, but liver weight was reduced in near-term pregnant rats treated with 100 mg/kg EGME. EGME (50 mg/kg) reduced litter size and fetal body weight and caused a significant number of live fetuses to have visceral abnormalities. EGME (100 mg/kg) caused all fetuses to be resorbed. In nonpregnant rats, 100 mg/kg did not affect serum 1,25-dihydroxyvitamin D (1,25(OH) 2 D 3 ) 25-hydroxyvitamin D, ionic calcium, total calcium, or parathyroid hormone. EGME appeared to have a dose-dependent effect on calcium and vitamin D metabolism during gestation. On Day 21 of gestation, total calcium and ionic calcium were increased and 1,25(OH) 2 D 3 was reduced in rats treated with EGME compared with nontreated controls. However, significant alterations in calcium homeostasis were evident only in dams that completely resorbed their litters. The changes in calcium and vitamin D metabolism during gestation appear to be secondary to the EGME-induced loss of litters.
Slow variable dominance and phase resetting in phantom bursting.

Bursting oscillations are common in neurons and endocrine cells. One type of bursting model with two slow variables has been called ‘phantom bursting’ since the burst period is a blend of the time constants of the slow variables. A phantom bursting model can produce bursting with a wide range of periods: fast (short period), medium, and slow (long period). We describe a measure, which we call the ‘dominance factor’, of the relative contributions of the two slow variables to the bursting produced by a simple phantom bursting model. Using this tool, we demonstrate how the control of different phases of the burst can be shifted from one slow variable to another by changing a model parameter. We then show that the dominance curves obtained as a parameter is varied can be useful in making predictions about the resetting properties of the model cells. Finally, we demonstrate two mechanisms by which phase-independent resetting of a burst can be achieved, as has been shown to occur in the electrical activity of pancreatic islets.
Peak flow responses to landscape disturbances caused by the cataclysmic 1980 eruption of Mount St. Helens, Washington

Years of discharge measurements that precede and follow the cataclysmic 1980 eruption of Mount St. Helens, Washington, provide an exceptional opportunity to examine the responses of peak fl ows to abrupt, widespread, devastating landscape disturbance. Multiple basins surrounding Mount St. Helens (300‐1300 km 2 drainage areas) were variously disturbed by: (1) a debris avalanche that buried 60 km 2 of valley; (2) a lateral volcanic blast and associated pyroclastic fl ow that destroyed 550 km 2 of mature forest and blanketed the landscape with silt-capped lithic tephra; (3) debris fl ows that reamed riparian corridors and deposited tens to hundreds of centimeters of gravelly sand on valley fl oors; and (4) a Plinian tephra fall that blanketed areas proximal to the volcano with up to tens of centimeters of pumiceous silt, sand, and gravel. The spatially complex disturbances produced a variety of potentially compensating effects that interacted with and infl uenced hydrological responses. Changes to water transfer on hillslopes and to fl storage and routing along channels both enhanced and retarded runoff. Rapid posteruption modifi cations of hillslope surface textures, adjustments of channel networks, and vegetation recovery, in conjunction with the complex nature of the eruptive impacts and strong seasonal variability in regional climate hindered a consistent or persistent shift in peak discharges. Overall, we detected a short-lived (5‐10 yr) increase in the magnitudes of autumn and winter peak fl ows. In general, peak fl ows were larger, and moderate to large fl ows (>Q 2 yr ) were more substantively affected than predicted by early modeling efforts. Proportional increases in the magnitudes of both small and large fl ows in basins subject to severe channel disturbances, but not in basins subject solely to hillslope disturbances, suggest that eruptioninduced modifi cations to fleffi ciency along alluvial channels that have very mobile beds differentially affected fl ows of various magnitudes and likely played a prominent, and additional, role affecting the nature of the hydrological response.
A lead bromide laser operating at 722.9 and 406.2 nm

A self-heated laser, operating on the atomic lead transitions at 722.9 and 406.2 nm is reported. The free lead atoms were produced by electric-discharge dissociation of lead bromide which was generated in situ by flowing a Ne-HBr gas mixture over molten Pb in the laser tube. The experimental technique may be applied readily to a number of metal-vapor lasers. Also reported is stable high-PRF operation on the 406.2 nm transition of lead. >
Direct retrieval of wind from total ozone mapping spectrometer (TOMS) data: Examples from FASTEX

The quantitative relationship between ozone and potential vorticity, and hence balanced wind and temperature, is examined using observations collected for a one-month period by the total ozone mapping spectrometer (TOMS). Ozone data are compared with Ertel potential vorticity (PV) integrated vertically from 500 to 50 mb, obtained from the NCEP/NCAR (National Centers for Environmental Prediction/National Center for Atmospheric Research) reanalysis archive. By performing a simple time filtering we isolate synoptic-scale transients in the ozone and PV. We show that the previously reported high correlation between PV and ozone is actually variable from day to day. the correlation also shows strong latitudinal dependence, with essentially no correlation in the tropics and high correlation in middle latitudes. A method is introduced to derive a three-dimensional PV representation from ozone data and a background field taken from the reanalysis data. PV-inversion methods are then used to recover balanced winds and temperatures and geopotential heights which may be compared to the analysed fields. Results suggest that many of the upper-tropospheric synoptic-scale wind perturbations may be recovered from the ozone data. A systematic error in the retrieval method used here is the understimation of the strength of upper-level ridges, corresponding to an excess of vertically integrated ozone compared with integrated PV. We discuss reasons for this difference.
Deprotonations and Charges of Well-Defined {Mo72Fe30} Nanoacids Simply Stepwise Tuned by pH Allow Control/Variation of Related Self-Assembly Processes

The solution behavior of the largest inorganic acid known thus far, the neutral, spherical iron/molybdenum/oxide nanocluster {Mo72Fe30} ([triple bond{(MoVI) MoVI5}12FeIII30 1a), including the pH-controlled deprotonation, is reported. The acidic properties are due to the 30 peripheral, weakly acidic FeIII(H2O) groups that form a unique Archimedean solid with all edges and dihedral angles being equal, the icosidodecahedron, and therefore an "isotropic" surface. Interestingly, the aqueous solutions are stable even for months because of the inertness of the spherical solutes and the presence of the hard FeIII and MoVI centers. The stability can be nicely proven by the very characteristic Raman spectrum showing, because of the (approximately) icosahedral symmetry, only a few lines. Whereas the {Mo72Fe30} clusters exist as discrete, almost neutral, molecules in aqueous solution at pH < 2.9, they get deprotonated and self-associate into single-layer blackberry-type structures at higher pH while the assembly process (i.e., the size of the final species) can be controlled by the pH values; this allows the deliberate generation of differently sized nanoparticles, a long-term goal in nanoscience. The average hydrodynamic radius (Rh) of the self-assembled structures decreases monotonically with increasing number of charges on the {Mo72Fe30} macroanions (from approximately 45 nm at pH approximately 3.0 to approximately 15 nm at pH approximately 6.6), as studied by laser light scattering and TEM techniques. The {Mo72Fe30} macroions with high-stability tunable charges/surfaces, equal shape, and masses provide models for the understanding of more complex polyelectrolyte solutions while the controllable association and dissociation reported here of the assembled soft magnetic materials with tuneable sizes could be interesting for practical applications.
Polo-like kinase-1 regulates kinetochore-microtubule dynamics and spindle checkpoint silencing.

Polo-like kinase-1 (Plk1) is a highly conserved kinase with multiple mitotic functions. Plk1 localizes to prometaphase kinetochores and is reduced at metaphase kinetochores, similar to many checkpoint signaling proteins, but Plk1 is not required for spindle checkpoint function. Plk1 is also implicated in stabilizing kinetochore–microtubule attachments, but these attachments are most stable when kinetochore Plk1 levels are low at metaphase. Therefore, it is unclear how Plk1 function at kinetochores can be understood in the context of its dynamic localization. In this paper, we show that Plk1 activity suppresses kinetochore–microtubule dynamics to stabilize initial attachments in prometaphase, and Plk1 removal from kinetochores is necessary to maintain dynamic microtubules in metaphase. Constitutively targeting Plk1 to kinetochores maintained high activity at metaphase, leading to reduced interkinetochore tension and intrakinetochore stretch, a checkpoint-dependent mitotic arrest, and accumulation of microtubule attachment errors. Together, our data show that Plk1 dynamics at kinetochores control two critical mitotic processes: initially establishing correct kinetochore–microtubule attachments and subsequently silencing the spindle checkpoint.
Class-based n -gram models of natural language

We address the problem of predicting a word from previous words in a sample of text. In particular, we discuss n-gram models based on classes of words. We also discuss several statistical algorithms for assigning words to classes based on the frequency of their co-occurrence with other words. We find that we are able to extract classes that have the flavor of either syntactically based groupings or semantically based groupings, depending on the nature of the underlying statistics.
Quantifying the benefits of ultrahigh energy resolution for gamma-ray spectrometry

Cryogenic Gamma-ray spectrometers operating at temperatures of ∼0.1 K provide an order of magnitude better energy resolution than conventional germanium detectors. Ultra-high energy resolution improves the accuracy of non-destructive analysis of nuclear materials, since a better separation of lines reduces statistical errors as well as systematic errors from background subtraction and efficiency correction. We are developing cryogenic Gamma-spectrometers based on bulk tin absorbers and superconducting molybdenum-copper sensors for nuclear forensics and non-proliferation applications. Here we quantify the improvements in accuracy for isotope analysis with cryogenic detectors in terms of detector performance for different cases of line separation, line intensity ratios and background levels. Precise measurements of isotope ratios are crucial in the context of nuclear attribution, since they provide signatures of composition, age, origin, intended purpose and processing history of illicit nuclear materials. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical Evaluation of P-multigrid Method for the Solution of Discontinuous Galerkin Discretizations of Diffusive Equations

This paper describes numerical experiments with P-multigrid to corroborate analysis, validate the present implementation, and to examine issues that arise in the implementations of the various combinations of relaxation schemes, discretizations and P-multigrid methods. The two approaches to implement P-multigrid presented here are equivalent for most high-order discretization methods such as spectral element, SUPG, and discontinuous Galerkin applied to advection; however it is discovered that the approach that mimics the common geometric multigrid implementation is less robust, and frequently unstable when applied to discontinuous Galerkin discretizations of di usion. Gauss-Seidel relaxation converges 40% faster than block Jacobi, as predicted by analysis; however, the implementation of Gauss-Seidel is considerably more expensive that one would expect because gradients in most neighboring elements must be updated. A compromise quasi Gauss-Seidel relaxation method that evaluates the gradient in each element twice per iteration converges at rates similar to those predicted for true Gauss-Seidel.
Identification of ribosomal RNA genes in metagenomic fragments

Motivation: Identification of genes coding for ribosomal RNA (rRNA) is considered an important goal in the analysis of data from metagenomics projects. Here, we report the development of a software program designed for the identification of rRNA genes from metagenomic fragments based on hidden Markov models (HMMs). This program provides rRNA gene predictions with high sensitivity and specificity on artificially fragmented genomic DNAs. Availability: Supplementary files, scripts and sample data are available at http://tools.camera.calit2.net/camera/meta_rna. Contact: liwz@sdsc.edu Supplementary information:Supplementary Data are available at Bioinformatics online.
A Laboratory-intensive Course on RNA Interference and Model Organisms

RNA interference (RNAi) is a powerful method to silence gene expression in a variety of organisms and is generating interest not only as a useful tool for research scientists but also as a novel class of therapeutics in clinical trials. Here, we report that undergraduate and graduate students with a basic molecular biology background were able to demonstrate conceptual knowledge and technical skills for using RNAi as a research tool upon completion of an intensive 8-wk RNAi course with a 2-h lecture and 5-h laboratory per week. Students were instructed on design of RNAi experiments in model organisms and perform multiweek laboratory sessions based on journal articles read and discussed in class. Using Nicotiana benthamiana, Caenorhabditis elegans, and mammalian cell culture, students analyzed the extent of silencing using both qualitative assessment of phenotypic variations and quantitative measurements of RNA levels or protein levels. We evaluated the course over two semesters, each with a separate instructor. In both semesters, we show students met expected learning outcomes as demonstrated by successful laboratory experiment results, as well as positive instructor assessments of exams and lab reports. Student self-assessments revealed increased confidence in conceptual knowledge and practical skills. Our data also suggest that the course is adaptable to different instructors with varying expertise.