cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling-Error-Driven Performance-Seeking Direct Adaptive Control

This paper presents a stable discrete-time adaptive law that targets modeling errors in a direct adaptive control framework. The update law was developed in our previous work for the adaptive disturbance rejection application. The approach is based on the philosophy that without modeling errors, the original control design has been tuned to achieve the desired performance. The adaptive control should, therefore, work towards getting this performance even in the face of modeling uncertainties/errors. In this work, the baseline controller uses dynamic inversion with proportional-integral augmentation. Dynamic inversion is carried out using the assumed system model. On-line adaptation of this control law is achieved by providing a parameterized augmentation signal to the dynamic inversion block. The parameters of this augmentation signal are updated to achieve the nominal desired error dynamics. Contrary to the typical Lyapunov-based adaptive approaches that guarantee only stability, the current approach investigates conditions for stability as well as performance. A high-fidelity F-15 model is used to illustrate the overall approach.
Colonic myoelectric activity in persons with spinal cord injury.

Colonic myoelectric activity was recorded from six para- or quadriplegic subjects with spinal cord injury and seven normal controls via bipolar electrodes in contact with the rectal mucosa. Recordings were carried out in the fasting (basal) state and after stimulation by a standard meal and by 1.0 mg neostigmine intramuscularly. The recordings were visually analyzed for spike activity, average slow wave frequency, and percentage occurrence of subsets of slow wave frequency (2–4 and 5–12 cycles/min). The spinal-cord-injured subjects had significantly more spike wave activity in the basal state than did the controls (12.6 spikes per 10 min vs 3.3). However, meal stimulation did not lead to an increase in spike activity in the spinal-cord-injured subjects (13.7 spikes per 10 min vs 12.6) while it did in the controls (6.4 vs 3.3 spikes per 10 min). Neostigmine significantly increased spike activity in both groups. There was no difference in average slow wave frequency nor any slow wave subsets between the two groups studied. Thus persons with spinal cord injuries have higher basal colonic myoelectric activity than normals but lack a demonstrable gastrocolic reflex. We conclude that the central nervous system exerts a tonic inhibitory influence on basal colonic motility and appears to participate in the gastrocolic reflex.
The rapid placement of jejunal feeding tubes: the Setdinger technique applied to the gut

The jejunal placement of enteral feeding tubes can be quite difficult. There are three methods for positioning naso-enteral tubes or tubes placed through a gastrostomy. These require blind passage of a weighted tube into the stomach allowing peristalsis to propel the tube into the small intestine, radiographic placement with fluoroscopic manipulation, or endoscopic placement of the tube with direct vision techniques. 9 All methods have limitations. With duodenal placement, backwash of fluid or retrograde movement of the weighted feeding tube into the stomach can occur. Weighted tubes may require a few days to pass out of the stomach and placement beyond the ligament of Treitz is often not accomplished. Endoscopic placement often fails due to friction between the feeding tube and the endoscope as the latter is withdrawn. Placement of the feeding ports beyond the ligament of Treitz is the only method that will ensure that the tube will not fall back toward the stomach and that feeding will not reflux into the stomach. We have applied a guide wire technique to insert a 12 French feeding tube to achieve a rapid and reliable placement of jejunal tubes both naso-enterally and through pre-existing gastrostomies.
Damping Shaft Torsional Oscillations Using a Dynamically Controlled Resistor Bank

The technical feasibility of using a dynamically controlled, three phase resistor bank to damp shaft torsional oscillations in large steam turbo-generators is examined. Torsional damping is achieved using a straightforward control strategy based on generator speed. A study system is defined and the shaft torques following various electrical system disturbances are computed and analyzed. It is shown that substantial damping can be achieved with a relatively small resistor bank, thus reducing the risk of significant shaft damage due to electrical disturbances.
Simulations of allosteric motions in the zinc sensor CzrA.

The zinc sensing transcriptional repressor Staphylococcus aureus CzrA represents an excellent model system to understand how metal sensor proteins maintain cellular metal homeostasis. Zn(II) binding induces a quaternary structural switch from a “closed” conformation to a more “open” conformation, reducing the DNA binding affinity by 4 orders of magnitude. In this study, we use classical molecular dynamics and quantum mechanical/molecular mechanical molecular dynamics simulations to investigate the molecular basis for the large conformational motions and allosteric coupling free energy (∼6 kcal/mol) associated with Zn(II) binding. Our simulations successfully capture the closed to open allosteric switching in DNA bound CzrA on Zn(II) binding. They reveal that zinc binding quenches global conformational sampling by CzrA, whereas DNA binding enhances the mobility of residues in the allosteric metal binding sites. These findings are in close agreement with experiments. We also identify networks of residues in...
Geothermal Potential of Deep Sedimentary Basins in the United States

Geothermal energy development has a promising future as part of a broad energy supply mix to meet growing demand in the United States and globally. Currently developed hydrothermal systems are a significant energy source, but these systems have limited geographic extent. Research is underway, including ongoing pilot projects, to evaluate the potential for EGS, or Engineered Geothermal Systems, to drill into hot crystalline rock, and create fractured reservoirs suitable for water injection and production cycles. However, a challenge to the economics of these systems is the drilling and fracturing cost. Co-production of geothermal energy associated with oil operations has been demonstrated successfully at Teapot Dome, where produced water is of sufficient quantity and adequate temperature to generate electricity with binary/hybrid systems. However, this approach has yet to be embraced by the oil industry. A potential new path toward expanded geothermal energy production is to use known porous and permeable reservoir rocks in appropriate sedimentary basins, where those packages of rocks have sufficient temperature, thickness, porosity, and permeability, existing at depths that are not so great that drilling costs make the potential system uneconomic. This presentation describes a DOE-funded project to identify, screen, and model these potential systems, incorporating geology, engineering, and economic modeling disciplines. From a geologic perspective, 17 basins in the western U.S. have been examined. Stratigraphic columns were compiled, including unit depths and thicknesses, along with thermal profiles. Target reservoir sections at appropriate depths and temperatures have been evaluated with respect to porosity and permeability, primarily from available core data, supplemented with wire-line log analysis. For screening purposes, thresholds of 125 °C temperatures were applied to meet economic targets. Results indicate that many of those basins should be excluded, for example, the Bighorn Basin of Wyoming has favorable porous and permeable reservoir rocks and good temperatures for geothermal energy production, but these occur at nearly 6 km, too deep for economic drilling costs. The temperature at the 4 km threshold is only 100-110 °C, in the marginal range for binary geothermal power systems. Based on this work, basins meeting the criteria are the Williston, Denver, Great Basin, Fort Worth, Sacramento, Gulf Coast, and Imperial Valley.
Pathogenesis and treatment of growing skull fractures.

BACKGROUND Growing skull fractures are poorly understood complications of pediatric skull fractures. METHODS A retrospective review of skull fractures at our institution from 1980-1993 revealed 10 patients with growing skull fractures. The age at injury ranged from 1-144 months, with 9 of 10 patients being under one year of age. The etiology of these fractures included falls, motor vehicle accidents, and child abuse. On average, growth of the fracture was diagnosed 14 months after the initial injury. RESULTS Six patients have had magnetic resonance imaging (MRI) with one demonstrating leptomeningeal cyst herniation, two having brain herniation, and three having both brain parenchyma and leptomeningeal cyst herniation. All patients had malacic cortex underlying the fracture, but there was no evidence of intracranial hypertension. Nine patients have undergone craniotomy with excision of granulation tissue and gliotic brain, dural repair, and cranioplasty using surrounding normal skull. There were no surgical complications or recurrences. CONCLUSIONS Brain/leptomeningeal cyst herniation through a dural rent, without MRI evidence of increased intracranial pressure, implicates physiologic growth and brain cerebrospinal fluid (CSF) pulsations as the cause of fracture enlargement.
Community-acquired methicillin-resistant Staphylococcus aureus skin infection: a retrospective analysis of clinical presentation and treatment of a local outbreak.

Abstract Background Methicillin-resisant Staphylococcus aureus (MRSA), a well-known nosocomial pathogen, is now emerging as a prominent cause of community acquired infections. We have noted an increase in number of cutaneous infections in Los Angeles over the past 2 years. The objective of the current study is to evaluate the clinical presentation and treatment of community acquired MRSA skin infections. Methods A retrospective chart review of 39 patients with 46 involved sites was performed. The sites of infection, morphology, antimicrobial susceptibility, and definitive treatment were evaluated. Results Cutaneous abscesses were the most common presentation of cutaneous MRSA infection. Definitive treatment consisted of incision and drainage in combination with antimicrobial therapy. The most effective antibiotics were vancomycin, trimethoprim/sulfamethoxazole in combination with rifampin, and linezolid. Conclusion Community acquired MRSA infection appears to be a growing problem requiring prompt diagnosis and treatment. First line treatment is incision and drainage in combination with linezolid, vancomycin, or combination trimethoprim/sulfamethoxazole and rifampin.
Caffeine reduces resting-state BOLD functional connectivity in the motor cortex.

In resting-state functional magnetic resonance imaging (fMRI), correlations between spontaneous low-frequency fluctuations in the blood oxygenation level dependent (BOLD) signal are used to assess functional connectivity between different brain regions. Changes in resting-state BOLD connectivity measures are typically interpreted as changes in coherent neural activity across spatially distinct brain regions. However, this interpretation can be complicated by the complex dependence of the BOLD signal on both neural and vascular factors. For example, prior studies have shown that vasoactive agents that alter baseline cerebral blood flow, such as caffeine and carbon dioxide, can significantly alter the amplitude and dynamics of the task-related BOLD response. In this study, we examined the effect of caffeine (200 mg dose) on resting-state BOLD connectivity in the motor cortex across a sample of healthy young subjects (N = 9). We found that caffeine significantly (p < 0.05) reduced measures of resting-state BOLD connectivity in the motor cortex. Baseline cerebral blood flow and spectral energy in the low-frequency BOLD fluctuations were also significantly decreased by caffeine. These results suggest that caffeine usage should be carefully considered in the design and interpretation of resting-state BOLD fMRI studies.
On-sky demonstration of optimal control for adaptive optics at Palomar Observatory

High-order adaptive optics systems often suffer from significant computational latency, which ultimately limits the temporal error rejection bandwidth when classical controllers are employed. This Letter presents results from an on-sky, real-time implementation of an optimal controller on the PALM-3000 adaptive optics system at Palomar Observatory. The optimal controller is computed directly from open-loop wavefront measurements using a multichannel subspace system identification algorithm, and mitigates latency by explicitly predicting incident turbulence. Experimental results show a significant reduction in the residual wavefront error over the controlled spatial modes, illustrating the superior performance of the optimal control approach versus the nominal integral control architecture.
Studies of the mechanisms of metabolism of diethyl p-nitrophenyl phosphorothionate (parathion) by rabbit liver microsomes☆

Abstract Based on the protein content of microsomes, the administration of 3-methylcholanthrene (3-MC) and phenobarbital (PB) to adult rabbits leads to an increased rate of metabolism of parathion (diethyl 4-nitrophenyl phosphorothionate) by rough-surfaced and whole microsomes but not by smooth-surfaced microsomes. Although prior administration of both PB and 3-MC increased the cytochrome P-450 content of the microsomes, when the rate of metabolism of parathion was calculated on the basis of the concentration of cytochrome P-450 in these microsomes, there is no difference in the rate of metabolism of parathion by rough-surfaced and smooth-surfaced microsomes from the untreated, 3-MC-treated and PB-treated animals. However, based on the cytochrome P-450 concentration, the rate of metabolism of parathion by whole microsomes from 3-MC and PB-treated animals is less than the rate with whole microsomes from untreated animals. Further studies have shown there is no correlation between the concentration of high spin or low spin cytochrome P-450 in any of the microsomal fractions or subfractions and the rate of metabolism of parathion to paraoxon or diethyl phosphorothionate.
Surface structure of Si(111)-5 × 1-Au characterized by impact collision ion scattering spectroscopy

Abstract Impact collision ion scattering spectroscopy (ICISS) has been used to characterize the Si(111)−5 × 1-Au surface, which was prepared by depositing about 0.4 monolayer (ML) of Au on a 7 × 7 Si(111) surface and annealing at 700°C. The experimental data clearly showed that the Au atoms causing the 5×1 structure were at least 0.7 A above the outermost Si layer. A comparison of the ICISS results with computer simulations gave excellent agreement for a model of the Au-atom arrangement proposed by Le Lay that consisted of three domains with strings of Au atoms arranged along the [ 1 10 ]-type azimuths in the Si(111) plane.
Thermal fatigue life prediction of flip chip solder joints by fracture mechanics method

Abstract The J -integral and stress intensity factor around the crack tips of a self-stretching flip chip solder joint under thermal fatigue crack propagation are determined by the finite element method. A 5th order polynomial is used to best fit the J -integral and stress intensity factor as a function of the crack length in the solder joint. Thermal fatigue life of the solder joint is then estimated based on the calculated J -integral and stress intensity factor, Paris' law, and fatigue crack growth rate data on solders. A correlation between the analytical and experimental results is made.
The Illiberal Culture of E-Democracy

Abstract Efforts to create e-democracy do not necessarily enhance liberal democratic politics, tending instead toward illiberal polities because of the underlying technological culture of e-democracy. Technologies are not value-neutral artifacts but rather social practices in which values and meanings are central elements. The complex of values and meanings creates a culture to each technology that is implemented along with that technology. Implementing a technology thus moves society in the direction of the underlying culture of the technology. Electronic liberal democracy cannot be constructed by simply adapting Internet-based technologies as is because the underlying culture of those technologies, when implemented in specifically political practices, runs counter to the principles of liberal democracy. Three aspects of that culture in particular-that the Internet is a commodity, that direct democracy is the most preferable form of democracy, and that the Internet is an individualized public forumshape ...
Linear and non-linear filters for clutter cancellation in radar systems

Abstract The theme of this paper is the cancellation of clutter echoes in modern coherent radar systems. The receiver operating characteristics (ROC) of the following clutter filters are compared: (a) optimum linear filter, (b) the linear filter with Chebyshev tapering, and (c) the non-linear filter which takes the minimum between the outputs of few linear filters which process the same radar signals with properly selected weights. The non-linear filter offers a performance advantage, with respect to the widely used filter (b), in terms of detection capability of a target with Doppler frequency close to the clutter mean Doppler frequency. The non-linear filter requires, in general, five times the computation load of the linear filter (b) but is much less computationally expensive than the optimum linear filter (a).
Quantitative real-time PCR detection of adenovirus in clinical blood specimens: a comparison of plasma, whole blood and peripheral blood mononuclear cells

Abstract Background Detection and quantification of adenovirus (ADV) in peripheral blood specimens has become an increasingly important tool in the management of immunosuppressed patients. Investigators have described the use of whole blood (WB), peripheral blood mononuclear cells (PBMC), serum and plasma but no studies have compared the utility of these different sample types for use in a clinical diagnostic assay. Objectives To determine the optimal blood compartment for quantitative real-time measurement of adenovirus in peripheral blood specimens. Study design WB, PBMC, and plasma representing 338 samples from 148 patients were tested for ADV by quantitative real-time PCR (qrt-PCR) and the results compared for concordance of both qualitative sensitivity and viral load among positive specimens. Results There was no significant difference in qualitative sensitivity among the three tested specimen types. Quantitative values of WB and plasma were similar and tended to be greater than those found in PBMC samples. Comparison of consecutive positive samples within individual patients showed that viral loads tracked similarly over time, irrespective of the sample type tested. Conclusion While WB and plasma do not offer a significant increase in sensitivity over PBMC, they may offer benefits in terms of reduced processing costs and laboratory turn around time.
A Survey of Institutional Practices Concerning the MBA Integrating Experience

Abstract Current institutional practices associated with the design and implementation of the AACSB-required “integrating experience” for the master of business administration degree are reviewed. The authors surveyed 547 colleges and universities concerning practices with respect to the integrating experience. They examined alternative forms of integration and faculty attitudes toward their institutions' practices. Several implications for the authors' findings are discussed.
Microchip for subcellular mechanics study in living cells

This paper reports a PDMS microchip for subcellular mechanics study, which consists of micrometer scale polymeric pillars on a plain substrate for cellular force measurement. The chip reported here differs from those proposed in previous work in that a flexible polymer microfabrication technique was applied for manufacturing the polymeric microstructures with various aspect ratios. This allows for the measurement of a range of forces encountered at the subcellular level. The microchip was integrated with a perfusion chamber to allow for precise control of the extracellular environment, thus facilitating cellular mechanics studies under various physiological conditions. A biocompatibility test was carried out using two types of mammalian cells (fibroblasts and cardiac myocytes). The results show satisfactory abundances of both types of cells, with no adverse affect of the PDMS microchip on cell viability. A proof-of-concept force measurement was performed in single contracting cardiac myocytes. The force distribution with a subcellular resolution conforms to the physiologic behavior of cardiac myoctes, indicating the potential application of the reported microchip in subcellular mechanics study.
Real-time wavefront control for the PALM-3000 high order adaptive optics system

We present a cost-effective scalable real-time wavefront control architecture based on off-the-shelf graphics processing units hosted in an ultra-low latency, high-bandwidth interconnect PC cluster environment composed of modules written in the component-oriented language of nesC. The architecture enables full-matrix reconstruction of the wavefront at up to 2 KHz with latency under 250 us for the PALM-3000 adaptive optics systems, a state-of-the-art upgrade on the 5.1 meter Hale Telescope that consists of a 64 x 64 subaperture Shack-Hartmann wavefront sensor and a 3368 active actuator high order deformable mirror in series with a 241 active actuator tweeter DM. The architecture can easily scale up to support much larger AO systems at higher rates and lower latency.
On multiple objective programming problems with set functions

Abstract The convexity of a subset of a σ-algebra and the convexity of a set function on a convex subset are defined. Related properties are also examined. A Farkas-Minkowski theorem for set functions is then proved. These results are used to characterize properly efficient solutions for multiple objective programming problems with set functions by associated scalar problems.
The Facilitative Influence of Instructional Objectives

AbstractSeveral studies have failed to demonstrate an advantage for Ss who receive instructional objectives. However, no test for the efficacy of instructional objectives has occurred with Ss who have had experience using them. In the present study Ss were used who had been provided with objectives for each unit of instruction throughout a semester. They were randomly given one of two sets of objectives and later quizzed both with items which corresponded and which did not correspond to their objectives. Overall, Ss performed significantly better on items which corresponded to the objectives they had been provided. An item analysis comparing both groups is presented.
Thermal transformations in mechanically alloyed Fe-Zn-Si materials

The ball milling of elemental powders corresponding to Γ (Fe3Zn10)+0.12 wt pct Si; Γ1 (Fe5Zn21) + 0.12 wt pct Si; δ (FeZn7)+0.12 wt pct Si; and ζ (FeZn13)+0.12 wt pct Si composition ratios yields crystalline, mechanically alloyed phases. Differential scanning calorimetry (DSC) measurements of these materials show that they evolve differently, with well-defined characteristic stages. The activation energies for processes corresponding to these stages, based on kinetic analyses, are determined and correlated to microstructural evolvements. The processes occurring during the first stage below 250 °C, for all of the materials studied using X-ray diffraction (XRD) analysis, are associated with release of strain, recovery, and limited atomic diffusion. The activation energies for recovery processes are 120 kJ/mole for the Γ+0.12 wt pct Si, 131 kJ/mole for δ+0.12 wt pct Si, and 96 kJ/mole for ζ+0.12 wt pct Si alloys. At higher temperatures, recrystallization and other structural transformations occur with activation energies of 130 and 278 kJ/mole for Γ+0.12 wt % Si; of 161 kJ/mole for Γ1+0.12 wt pct Si; of 167 and 244 kJ/mole for δ+0.12 wt pct Si; and of 641 kJ/mole for the ζ+0.12 wt pct Si. In addition, a eutectic reaction at 420 °C±3 °C, corresponding to the Zn-Si system, and a melting of Zn in Fe-Zn systems are observed for the ζ+0.12 wt pct Si material. The relation of FeSi formation in the Sandelin process is discussed.
Isomeric Intraconversion among Penta- and Hexacoordinate Cyclic Oxyphosphoranes via Oxygen Atom Coordination1,2

The synthesis of a series of cyclic pentaoxyphosphoranes containing a sulfonyl group was carried out by the reaction of either P(OCH2CF3)3 or P(OPh)3 with the appropriate diol in an oxidative addit...
The PhyloCode and the Distinction between Taxonomy and Nomenclature

In a recent report on the First International Phylo genetic Nomenclature Meeting, Pickett (2005:81) con cluded that the "architects of the PhyloCode have reversed their positions on the three main points of contention that they have articulated for some 15 years? namely that taxonomy must be a monophyletic, rank less, system that rejects the type concept." Contrary to Pickett's interpretation, advocates of the PhyloCode have not reversed their positions on any of these is sues. The rejection of nomenclatural types (which should not be confused with typological or essentialist philoso phies) was never a fundamental principle of phylo genetic nomenclature (see de Queiroz and Gauthier, 1992:459-460), and the reason that the PhyloCode does not prohibit the recognition of nonmonophyletic taxa or the use categorical ranks is simply that it is a code of nomenclature rather than of taxonomy In this paper, I highlight the distinction between taxonomy and nomen clature and use it to explain two of Pickett's misunder standings about the PhyloCode. My purpose is to call attention to this important but under-appreciated dis tinction using Pickett's criticisms of the PhyloCode as examples; it is not intended to be a point-by-point rebut tal of his criticisms (for such a rebuttal, see Laurin et al., 2005).
In vivo proton magnetic resonance spectroscopy studies of human brain

In vivo localized proton magnetic resonance spectroscopy (MRS) studies of brain were performed on eighteen normal subjects using the stimulated echo (STE) sequence. The absolute concentrations and proton relaxation times of N-acetyl aspartate (NAA), total creatine (Cr) and choline (Cho) were estimated. The MRS data was quantitatively analyzed for repeatability and intersubject variability. Quantitative analysis indicates excellent spectral repeatability. Significant intersubject variations in [NAA] and [Cr] have been observed while the intersubject variability in [Cho] has been found to be fairly small. Significant intensity distortions have been observed for mixing times longer than 50 msec.
Oligonucleotide Phosphonates—Solid Phase Synthesis and Biochemical Characterization

Abstract A novel method for the automated synthesis of oligonucleotide-3′-phosphonates is described. Oligonucleotide analogs synthesized by this method exhibited appreciable stability to exonuclease digestion.
Measurement of activated carbon and other black carbons in sediments.

Black carbon in sediment, present natively or added as a treatment amendment in the form of activated carbon, reduces contaminant bioavailability. Field evaluation of activated carbon effectiveness in reducing contaminant bioavailability requires accurate methods to measure the amendment in sediments. The most commonly used method to separate black carbon from natural organic matter in soils and sediments is low temperature (375 °C) thermal oxidation which resulted in significant losses of activated carbons. A method was developed to isolate activated carbon using a solution of concentrated sulfuric acid and potassium dichromate to oxidize the natural organic matter while preserving the activated carbon. The chemical oxidation method was applied to assess the delivery of activated carbon to sediments in a pilot-scale demonstration project carried out in Grasse River, NY. Using this method on sediment from the Grasse River, over 98% of the natural organic matter was removed while preserving at least 95% of the activated carbon. The method was also demonstrated on other carbonaceous geosorbents and native black carbon in several sediment samples.
Flame propagation of butanol isomers/air mixtures

Abstract An experimental and computational study was conducted on the propagation of flames of saturated butanol isomers. The experiments were performed in the counterflow configuration under atmospheric pressure, unburned mixture temperature of 343 K, and for a wide range of equivalence ratios. The experiments were simulated using a recent kinetic model for the four isomers of butanol. Results indicate that n-butanol/air flames propagate somewhat faster than both sec-butanol/air and iso-butanol/air flames, and that tert-butanol/air flames propagate notably slower compared to the other three isomers. Reaction path analysis of tert-butanol/air flames revealed that iso-butene is a major intermediate, which subsequently reacts to form the resonantly stable iso-butenyl radical retarding thus the overall reactivity of tert-butanol/air flames relatively to the other three isomers. Through sensitivity analysis, it was determined that the mass burning rates of sec-butanol/air and iso-butanol/air flames are sensitive largely to hydrogen, carbon monoxide, and C1–C2 hydrocarbon kinetics and not to fuel-specific reactions similarly to n-butanol/air flames. However, for tert-butanol/air flames notable sensitivity to fuel-specific reactions exists. While the numerical results predicted closely the experimental data for n-butanol/air and sec-butanol/air flames, they overpredicted and underpredicted the laminar flame speeds for iso-butanol/air and tert-butanol/air flames respectively. It was demonstrated further that the underprediction of the laminar flame speeds of tert-butanol/air flames by the model was most likely due to deficiencies of the C4-alkene kinetics.
Use of Agency Staff in Nursing Homes

This article describes the extent and degree of use of agency staff by nursing homes and examines the relationship between agency staffing levels and quality of care in a large sample of nursing homes (N = 3,876). The quality indicators came from the Nursing Home Compare Web site. It was found that many nursing homes used agency staff (approximately 60% used at least some), and a strong association between better quality and lower agency use existed for both nurse aides and RNs. The influence on quality for the highest levels of agency use, compared with no agency use, was clinically significant. On the basis of these findings, facilities considering using high levels of agency staff should do so carefully.
Bactericidal Effect of Several Chemicals on Hatching Eggs Inoculated with Salmonella serovar Typhimurium

Abstract Breeder flocks and commercial hatcheries represent an early contamination point for Salmonella entry into commercial integrated poultry operations. Utilizing effective antimicrobial treatments for hatching eggs is a critical part of reducing the incidence of Salmonella-colonized chicks on the farm. The objective of this study was to evaluate the bactericidal effect of several chemicals on Salmonella-contaminated hatching eggs. Four replications (n = 10/treatment per replicate) were conducted to determine the efficacy of 7 commercially available compounds. The compounds tested were as follows: 1) hydrogen peroxide, 2) water-oil emulsion droplets stabilized by detergent, 3) peroxyacetic acid, 4) 4 quaternary ammonium compounds attached to a polymer, 5) 2 quaternary ammonium compounds, 1 biguanide compound and bronopol attached to a polymer, 6) N-alkyl dimethyl benzyl ammonium chloride and stabilized urea, and 7) polyhexamethylenebiguanide hydrochloride. A naladixic acid-resistant Salmonella serovar Typhimurium was inoculated (103 cfu/mL) onto fertile hatching eggs by drip-inoculation. Controls included a positive control (no spray application) and a water control (spray containing water to take into account rinsing effects). Compounds 5 and 7 had a 100% reduction, and both of these chemicals included a biguanide. Compounds 4 and 3 were also effective with a 95 and 93.5% reduction, respectively. Compounds 6 and 2 were the least effective of all chemicals, with a reduction of 47.5 and 40%, respectively. Hydrogen peroxide (compound 1), which has been used by the poultry industry, had a 70% reduction, and the water control produced a 10% reduction due to the rinsing effect. Several antimicrobials tested were more effective than hydrogen peroxide. More detailed studies will be required to adequately evaluate these antimicrobials.
The nonmetal-metal transition and phase separation in the europium-ammonia system

Abstract The coexistence curve of EuNH 3 solutions has been determined by visual observation and electron paramagnetic resonance (EPR). A nonmetal-metal transition is evident in EuNH 3 solutions, and the miscibility gap is the most pronounced among the metal-ammonia ( M NH 3 ) systems that have been studied. The critical concentration and temperature are 1.30 mole% metal and 321 K, respectively. The coexistence curve has a parabolic shape within close vicinity of the critical point, which strongly suggests the existence of long-range interactions and cluster formation. EPR spectra indicate that the cation-electron interactions in these solutions are weak, so that the valence-electron concentration in MNH 3 solutions is probably the primary factor in determining the nature of the nonmetal-metal transition. The coexistence curve and associated critical parameters for EuNH 3 solutions are compared to those obtained for other M NH 3 solutions.
Query processing and file management issues in partitioned databases (abstract)

This study reviews the database partitioning techniques and elaborates on features of storage organization from efficiency and query processing standpoints. Methods for static files have excellent utilization records but require variable number of disk accesses, are prone to overflows, and may need re-organization when changes are made. Dynamic file schemes with directories have good retrieval query performance but tend to achieve low storage utilization, suffer from growing directory, and may propagate the effects of an update to several regions and possibly all the way up to the highest level directory.Partitioning very large databases has become an intense research area over the last few years. The characteristics of partitioned file organizations have profound effects on the efficiency of query processing and database updates.We have identified two main partitioning methodologies: static and dynamic files. While with static files we can achieve good utilization, they result in variable disk accesses per query and need frequent file reorganizations due to updates. As with the dynamic files we can achieve constant number of disk accesses for all queries at the expense of relatively low utilization (for uniform as well as non-uniform data distributions), directory sizes may grow fast, and handling of updates efficiently in extreme cases may be difficult.To this date very few has been researched in the area of updates of partitioned file organizations. However, as can be seen in our discussions there are important problems awaiting to be tackled in this area especially with respect to directory structures.
Coding-Aware Scheduling for Reliable Many-to-One Flows

We revisit the problem of scheduling the sources transmissions in a many-to-one flow to provide reliable communication between n sources and a single destination. The performance of coding-aware scheduling is studied based on both digital network coding (DNC) and analog network coding (ANC). We discuss some special cases in which an optimal ANC-based schedule can be constructed efficiently. Finally, we show that the maximum gain from using ANC is theoretically bounded by n, where n is the number of sources.
Capital Structure in Transition: Financial Strategy in China's Emerging Economy

During economic transition, firms must dramatically reduce their financial dependence on the state and begin to borrow from non-state capital sources. This paper draws on organizational theory to examine this fundamental transformation of firm capital structure during China's transition. I propose that managers borrowed from external sources even when internal funds were available because retained earnings were considered state assets. Firms used retained earnings to signal financial health but borrowed externally to reduce dependence on the state. Uncertainty during transformation also produced interfirm imitation of borrowing strategies, particularly imitation of local and high status others. Finally, I argue that levels of market development and changes in development over time affected firm borrowing strategies and that these strategies are best viewed as trajectories over time. Analysis of survey data on the capital structure of formerly state-owned firms from 1980 through 1989 provides support for these arguments and highlights the importance of institutional context in understanding corporate borrowing and strategic decision making.
‘Racial differences have to be considered’: Lauretta Bender, Bellevue Hospital, and the African American psyche, 1936-52

This paper examines one US psychiatrist's engagement between 1936 and 1952 with a racialist strain of evolutionary thought. When Lauretta Bender began working with Bellevue Hospital's disproportionately black population, the psychiatric literature still circulated the crude evolutionary proposition that blacks remained stuck at a more primitive stage of development. In the 1930s, drawing insights from holistic, mechanistic and environmentalist thinking on the relationship between mind and body, Bender developed her own more circumspect racialist position. Although she largely abandoned her underdetermined version of racialism in the 1940s for an approach that left out race as an active factor of analysis, this paper contends that she probably never wrote off black primitivity as a theoretical possibility.
Mild Cognitive Impairment and Everyday Function: An Investigation of Driving Performance

Mild Cognitive Impairment (MCI) involves subtle functional losses that may include decrements in driving skills. We compared 46 participants with MCI to 59 cognitively normal controls on a driving evaluation conducted by a driving rehabilitation specialist who was blinded to participants' MCI classification. Participants with MCI demonstrated significantly lower performance than controls on ratings of global and discrete driving maneuvers, but these differences were not at the level of frank impairments. Rather, performance was simply less than optimal, which to a lesser degree was also characteristic of a subset of the cognitively normal control group. The finding of significantly lower global driving ratings, coupled with the increased incidence of dementia among people with MCI and the known impact of dementia on driving safety, suggests the need for increased vigilance among clinicians, family members, and individuals with MCI for initially benign changes in driving that may become increasingly problematic over time.
Feasibility of real-time three-dimensional transoesophageal echocardiography for guidance of percutaneous atrial septal defect closure.

Aims Intracardiac echocardiography (ICE) and two-dimensional transoesophageal echocardiography (2D TEE) are used in most centres for guiding transcatheter atrial septal defect (ASD) closure. ASDs have complex shapes that are not well characterized with 2D imaging. Real-time 3D TEE (RT3D TEE) provides en-face visualization of the ASD, allowing precise assessment of ASD dimensions. Accordingly, our aims were (i) to determine the feasibility of RT3D TEE to guide ASD closure and (ii) to compare ASD and balloon dimensions (BDs) using RT3D TEE vs. ICE and 2D TEE. Methods and Results Thirteen patients with ostium secundum ASD underwent transcatheter ASD closure. 2D TEE, RT3D TEE, and ICE images were acquired sequentially. RT3D TEE was feasible in all patients. Comparing RT3D TEE and 2D imaging, the mean difference in long-axis dimension was +0.5 mm ( P = NS for both), and −1.4 mm in short-axis (2D TEE, P < 0.05; ICE, P = 0.06). BD was greater with 3D TEE vs. ICE (+0.9 mm). Conclusion RT3D TEE can be used to guide transcatheter ASD closure with the advantages of lower cost than ICE, and ability to visualize en-face views of the ASD. ASD and BD as measured by RT3D TEE differ when compared with 2D imaging.
Attenuating primaries and free‐surface multiples of vertical cable (VC) data while preserving receiver ghosts of primaries

Marine vertical cable (VC) data contain primaries, receiver ghosts, free‐surface multiples, and internal multiples just like towed‐streamer data. However, the imaging of towed‐streamer data is based on primary reflections, while the emerging imaging algorithms of VC data tend to use the receiver ghosts of primary reflections instead of the primaries themselves. I present an algorithm for attenuating primaries, free‐surface multiples, and the receiver ghosts of free‐surface multiples while preserving the receiver ghosts of primaries. My multiple attenuation algorithm of VC data is based on an inverse scattering approach known, which is a predict‐then‐subtract method. It assumes that surface seismic data are available or that they can be computed from VC data after an up/down wavefield separation at the receiver locations (streamer data add to VC data some of the wave paths needed for multiple attenuation). The combination of surface seismic data with VC data allows one to predict free‐surface multiples and...
General Strain Theory and Substance Use among American Indian Adolescents

Despite the well-established finding that American Indian adolescents are at a greater risk of illicit substance use and abuse than the general population, few generalist explanations of deviance h...
Polygons in Arrangements Generated by n Points.

Abstract : Generalizing a result of Sklyarskii-Cencov-Yaglom concerning partitions of a convex polygon by its diagonals, the following theorem is established: If F is a polygonal face of the arrangement generated in the plane by m points, then the number of sides of F is at most m if m is odd, and at most m-1 if m is even; both bounds are best possible. (Author)
Cooperative Control of Water Volumes of Parallel Ponds Attached to An Open Channel Based on Information Consensus with Minimum Diversion Water Loss

Decision making through information sharing for a canal irrigation system is discussed in this paper. A consensus-based decision algorithm is used to manage water distribution into a parallel ponds network and achieve good quality of service and minimum water-loss. The algorithm is tested in a simulation software reproducing the major dynamics of the system for different scenarios. While not taking into account some of the non-linearities and focusing on feasibility, the algorithm shows interesting results under ideal flow control conditions especially regarding convergence. Robustness is estimated by Monte Carlo evaluation of the effects of delay uncertainty, and the strategy maintains convergence.
Quantitative comparison of myocardial fiber structure between mice, rabbit, and sheep using diffusion tensor cardiovascular magnetic resonance

Accurate interpretations of cardiac functions require precise structural models of the myocardium, but the latter is not available always and for all species. Although scaling or substitution of myocardial fiber information from alternate species has been used in cardiac functional modeling, the validity of such practice has not been tested. Fixed mouse (n = 10), rabbit (n = 6), and sheep (n = 5) hearts underwent diffusion tensor imaging (DTI). The myocardial structures in terms of the left ventricular fiber orientation helix angle index were quantitatively compared between the mouse rabbit and sheep hearts. The results show that significant fiber structural differences exist between any two of the three species. Specifically, the subepicardial fiber orientation, and the transmural range and linearity of fiber helix angles are significantly different between the mouse and either rabbit or sheep. Additionally, a significant difference was found between the transmural helix angle range between the rabbit and sheep. Across different circumferential regions of the heart, the fiber orientation was not found to be significantly different. The current study indicates that myocardial structural differences exist between different size hearts. An immediate implication of the present findings for myocardial structural or functional modeling studies is that caution must be exercised when extrapolating myocardial structures from one species to another.
p19ARF and RasV12 Offer Opposing Regulation of DHX33 Translation To Dictate Tumor Cell Fate

DHX33 is a pivotal DEAH-box RNA helicase in the multistep process of RNA polymerase I-directed transcription of the ribosomal DNA locus. We explored the regulation of DHX33 expression by Ras(V12) and ARF to determine DHX33's role in sensing these opposing signals to regulate ribosome biogenesis. In wild-type primary fibroblasts, Ras(V12) infection induced a transient increase in DHX33 protein level, as well as an rRNA transcriptional rate that was eventually suppressed by a delayed activation of the ARF/p53 pathway. DHX33 expression was exclusively controlled at the level of translation. ARF caused a dramatic reduction in polysome-associated DHX33 mRNAs, while Ras(V12) led to a complete shift of existing DHX33 mRNAs to actively translating polysomes. The translation of DHX33 by Ras(V12) was sensitive to inhibitors of phosphatidylinositol 3-kinase, mTOR, and mitogen-activated protein and was pivotal for enhanced rRNA transcription and enhanced overall cellular protein translation. In addition, DHX33 knockdown abolished Ras(V12)-induced rRNA transcription and protein translation and prevented both the in vitro and in vivo transforming properties of oncogenic Ras(V12). Our results directly implicate DHX33 as a crucial player in establishing rRNA synthesis rates in the face of Ras(V12) or ARF signals, adjusting ribosome biogenesis to match the appropriate growth or antigrowth signals.
Assessing the Extent that the Gender and STEM Practice - Oriented Literature is Evidence-Based

One principal way to judge if the activity or program described in a practice-oriented publication is worth replicating is to consider the strength of its foundational component. A strong foundational component supports the credibility of an initiative by demonstrating that it was designed with an understanding of other similar initiatives and with evidence that there was a reasonable promise that the desired outcomes were realistically achievable. This paper reports on the findings of a mixed methods content analysis of 142 practice-oriented articles published in three different refereed venues between 1995 and 2009. A scale to measure the quality of the foundational component of the practice-oriented publications was used in the quantitative phases to test if there had been a change in the relative number and quality of practice-oriented publications over time. The validity of the scale was tested in subsequent qualitative phases of the project by an inductive examination of the characteristics of top-scoring articles. Results of the quantitative analysis indicated that the average quality rating of the foundational element of the articles was relatively low (3.37 out of a possible 6 points). The scale proved effective in distinguishing articles that were exemplary in other ways as well. The low overall quality score on the foundational component of practice-oriented publications either means that the authors of these publications are failing to provide ample documentation that these initiatives were evidence-based or the content analysis reveals a long-standing trend toward the adoption of non-evidence based practices.