cssi/SciSciGPT-SciSciNet huggingface dataset:
An Inducible Mammalian Amber Suppressor: Propagation of a Poliovirus Mutant

Abstract We describe a general protocol for controlled gene amplification, which allows conditional expression of high levels of amber suppressor activity in monkey kidney cells, and we demonstrate its use in the genetic analysis of animal viruses by the generation and propagation of the first nonsense mutant of poliovirus. A human amber suppressor tRNA Ser gene linked to the SV40 origin of replication and a second DNA carrying a temperature-sensitive SV40 large T antigen gene were cotransfected into monkey cells. Cell lines having stably integrated the DNAs were isolated. Shifting the cells from the nonpermissive temperature to a lower permissive temperature caused the amplification of the suppressor tRNA gene, which resulted in suppression efficiencies at amber codons of 50%–70%, as measured by suppression of an amber codon in the E. coli chloramphenicol acetyltransferase gene. A mutant of poliovirus, in which a serine codon in the replicase gene was converted to an amber codon, was efficiently propagated on the suppressor-positive cell lines. The mutant virus reverted to wild-type by a single base change to a serine codon at a frequency of approximately 2.5 × 10 −6 , surprisingly low for a RNA genome.
Evaluation of Plasma Strip Induced Substrate Damage

High dose, ultra shallow junction implant resist strip requires minimal substrate loss and dopant loss. Silicon recess (silicon loss) under the source/drain (S/D) extensions increases the S/D extension resistance and decreases drive currents by changing the junction profile. ITRS surface preparation technology roadmap [1] targets silicon loss to be 0.4A per cleaning step for 45nm and 0.3A for 32nm generation. Fluorine-containing chemistries which are often used to enhance implanted resist strip and residue removal result in unacceptable substrate loss. A non-fluorine plasma strip was developed in earlier work and is qualified for 45nm logic production [2]. The objective of this work is to study the substrate damage that is induced by the resist strip plasma process. Silicon surface oxidation and silicon loss of different plasma strip chemistries were evaluated with various metrologies such as optical ellipsometry, electrical oxide measurement, XPS, TEM and mass measurement. The impact of different strip chemistries on dopant retention and distribution is also discussed.
Trauma to the esophagus.

We have classified. esophageal trauma into three major categories: (1) Iatrogenic trauma including endoscopic perforation, trauma due to dilatation, surgical trauma, tube trauma, radiation trauma, and drug trauma; (2) Self-induced trauma including foreign bodies, corrosive or drug ingestion, and postemetic trauma; (3) Direct trauma including penetrating trauma and blunt trauma. Discussion and illustrative cases are presented.
ALPHANUMERIC SEQUENCING AND COGNITIVE IMPAIRMENT AMONG ELDERLY PERSONS

Alphanumeric Sequencing involves the alternating recitation of counting and the alphabet. We report data on the use of this measure among 112 VA patients ranging in age from 61 to 100 years who were administered the Alphanumeric Sequencing, Trail Making Test, Digits Forward and Backward, the Mini-Mental State Examination, and the Behavioral Dyscontrol Scale. Persons who obtained scores < 27 on the Mini-Mental State Examination or < 14 on the Behavioral Dyscontrol Scale performed significantly more poorly than those who scored higher. Both the time and errors were correlated (.11 to -.49) with measures of information processing and short-term memory.
Theoretical analysis of hall factor and hall mobility in p-type silicon☆

Abstract Using a two-band (i.e. heavy-hole and light-hole band) model and the relaxation time approximation, the Hall factor was calculated for the case of silicon doped with boron. Contributions from scattering by acoustical and optical phonons and by ionized and neutral impurities were considered. In addition, the effects of hole-hole scattering, as well as valence band nonparabolicity and anistropy were also taken into account. The scattering and anistropy factors were separately evaluated to emphasize their individual contributions to the Hall factor. Theoretical values of the Hall factor at 300 K vary between 0.882 and 0.714 over the dopant density ranges 1014 ≦ NA ≦ 3 × 1018 cm−3. Hall mobilities for p-type silicon were calculated and compared with published data 100 ≤ T ≤ 400 K and 1014 ≦ NA ≦ 3 × 1018 cm−3. The present model is limited to the case of uncompensated material and for the weak field in which μHB ⪡ 1.
RELATIVE ABUNDANCE, DISTRIBUTION AND INTER-SPECIFIC RELATIONSHIP OF CETACEAN SCHOOLS IN THE EASTERN TROPICAL PACIFIC

The relative abundance of the most common cetacean schools in the eastern tropical Pacific Ocean for 1977–1980 are estimated based on encounter rates with tuna purse-seiners. No temporal trends were apparent in the relative abundance estimates. The geographic distributions for eight different school types are described. Multivariate statistical techniques are used to investigate interrelations between species and relationships to parameters of the physical environment. The results suggest three major species groupings: (1) an inshore grouping of bottlenose dolphins (Tursiops truncates), Risso's dolphin (Grampus griseus), pilot whales (Globicephala macrorhynchus) and, to a lesser extent, common dolphins (Delphinus delphis); (2) an offshore pelagic grouping of spotted and spinner dolphins (Stenella attenuate and S. longirostris); and (3) an association between pilot whales and common dolphins that overlaps the first grouping in inshore areas and also tends to be segregated from the second grouping. The results also suggest that relative densities of different school types are strongly related to physical environmental parameters, the most important being sea surface temperature, depth of the thermocline and thickness of the oxygen minimum layer.
Leptin Directly Activates SF1 Neurons in the VMH, and This Action by Leptin Is Required for Normal Body-Weight Homeostasis

Leptin, an adipocyte-derived hormone, acts directly on the brain to control food intake and energy expenditure. An important question is the identity of first-order neurons initiating leptin's anti-obesity effects. A widely held view is that most, if not all, of leptin's effects are mediated by neurons located in the arcuate nucleus of the hypothalamus. However, leptin receptors (LEPRs) are expressed in other sites as well, including the ventromedial hypothalamus (VMH). The possible role of leptin acting in "nonarcuate" sites has largely been ignored. In the present study, we show that leptin depolarizes and increases the firing rate of steroidogenic factor-1 (SF1)-positive neurons in the VMH. We also show, by generating mice that lack LEPRs on SF1-positive neurons, that leptin action at this site plays an important role in reducing body weight and, of note, in resisting diet-induced obesity. These results reveal a critical role for leptin action on VMH neurons.
The burdens of parent care: A critical evaluation of recent findings

Abstract A critical evaluation of the parent-care literature reveals that the respondents are likely to be more disadvantaged with respect to social, physical and financial resources than is the case of the general population. Moreover, the interpretation of research findings is more pessimistic than is justified The generalizations that are being made from this research are likely to have negative effects on both policy formulation and the social construction of intergenerational relationships.
Moire deflectometry with deferred analysis.

A simplified version of moire deflectometry for flow visualization is presented. The modification comprises replacement of the second grating, the ground glass screen, and the camera with a plate film holder to obtain a shadow picture. Postanalysis proceeds by placing a grid transparency of the same periodicity of the remaining glass grating on the negative for projection viewing. The rotational angle between the grating and the plate alters the moire fringe periodicity. Use of the method in studying flows is predicted to reveal weak density gradient areas and shocks.
Controlling thermochromism in a photonic block copolymer gel.

The tunable properties of stimulus-responsive materials attract great interest in a variety of technological applications. Photonic gels are a new class of these materials, which can be tuned to reflect different wavelengths of light. Controlling this reflected color via temperature-induced changes of self-assembled photonic materials is important for their application in sensors and displays. In this work, the thermochromic behavior of a PS-P2VP photonic gel was found to originate from a temperature-induced change in the pK(a) of the P2VP blocks. Control was obtained through the manipulation of the solution pH. The findings of this work provide the basis for understanding and controlling the properties of thermochromic block copolymers fostering their use in technologically relevant applications.
Monthly clinic assignments for internal medicine housestaff

This article presents a new model for constructing monthly clinic schedules for interns and residents (i.e., housestaff) training in Internal Medicine. Clinical experiences during the three years of residency occur in inpatient and outpatient settings, and on generalist and specialist clinical services. These experiences include spending time in a primary care setting caring for an assigned group of patients over time. Housestaff rotate through different clinical experiences monthly, with their primary care clinic time overlaid longitudinally on these other clinical services. The exact amount of primary care time spent varies between clinical rotations. In fact, it is the variable clinic hour requirements that drive the scheduling process, and is what distinguishes our problem from most personnel scheduling problems. Typically, staff schedules are driven by shift or hourly demand and are designed to minimize some measure of cost. The objective in our work is to both maximize clinic utilization and minimiz...
Political Elites and Sex Differences in Political Ambition: A Reconsideration

This study examines the political ambitions of representative national samples of women and men holding comparable elective offices in 1981. In contrast to the findings of previous research on sex differences in political ambition, most of which focused on party activists, women are found to be as ambitious for public officeholding as their male counterparts. Two possible explanations for the differences in results between this and earlier studies are tested. The first is that the findings of earlier studies were misleading because they failed to control for officeholding status, thereby masking underlying similarities in the ambitions of women and men who had similar levels of officeholding experience. The second is that the ambitions of political women, relative to those of political men, increased over time. Because neither of these explanations receives empirical support, differential selection into party activist and public officeholding elites is suggested as the most likely reason for the differenc...
Measurement of solid-solid transformation rates by positron annihilation

Abstract Positron lifetime measurements have been used to obtain the rates of solid-solid phase transformations at 21°C in certain binary mixtures of n-eicosane and n-docosane.
Grading of gastric foveolar-type dysplasia in Barrett's esophagus

Dysplasia is the gold standard biomarker of cancer risk in Barrett's esophagus, but its diagnosis remains difficult. This is due in part to its multitude of histological appearances. One aspect receiving little attention concerns gastric-type Barrett's dysplasia, which is distinctly different from the well-established intestinal variant. Recognition of gastric-type dysplasia and development of separate grading criteria are required. The prevalence, diagnostic criteria, and natural history of gastric-type Barrett's dysplasia were systematically evaluated in 1854 endoscopic biopsies from a cohort of 200 consecutive Barrett's dysplasia patients. Goblet cells were present in all cases, confirming the utility of this defining feature of Barrett's esophagus. The prevalence of Barrett's gastric-type dysplasia was 15% at the patient level (30 of 200 patients) and 20% at the biopsy level (166 of 852 dysplastic biopsies). Gastric-type dysplasia uniformly showed non-stratified, basally oriented nuclei as the major criterion for distinguishing it from intestinal-type Barrett's dysplasia. As such, loss of nuclear polarity, as the most objective criterion to distinguish intestinal-type low- and high-grade dysplasia, cannot be applied to gastric-type dysplasia. Rather, discriminatory features included increased nuclear size with a high-grade dysplasia cutoff by receiver operating characteristic (ROC) analysis approximating 3-4 times the size of a mature lymphocyte, providing an optimal sensitivity, specificity, and area under the curve of 0.78, 0.90, and 0.90 (95% CI: (0.87, 0.93)), respectively. Crowded, irregular glandular architecture (P<0.001) was more common in high-grade lesions (P<0.001), as was eosinophilic and oncocytic cytoplasm relative to the mucinous cytoplasm (P<0.001), prominent nucleoli (P<0.001), mild nuclear pleomorphism (P<0.001), and villiform architecture (P<0.001). During follow-up, 64% (7 of 11) of patients with pure gastric and 26% (5 of 19) with mixed gastric and intestinal dysplasia underwent neoplastic progression. The recognition of Barrett's gastric-type dysplasia and use of the proposed grading criteria should promote better diagnostic classification of the Barrett's neoplastic spectrum.
The effect of calcium on the Distal P III component of the frog ERG.

Abstract The distal P III component of the frog electroretinogram has been previously shown to represent a massed receptor potential of the retina. This study, utilizing isolated frog retinas, has shown that the amplitude of the distal P III potential has a near linear relationship with the concentration of calcium. The amplitude is maximal for low concentrations of calcium and is significantly reduced with increasing concentrations of calcium. Although the amplitude of the distal P III potential was greatly influenced by the calcium concentration, there was very little effect noted on the temporal recovery of response following brief intensive stimulation as a function of the calcium concentration. The enhancement of the distal P III potential found in low calcium media is also reflected in an increase in the amplitude of the b-wave, which is generated by more proximal cells of the retina. However, a slight change of “gain” was noted in the relationship between the distal P III potential and the b-wave in the low calcium concentration media. The mode of action of calcium is discussed in terms of the regulation of ionic permeabilities and active transport mechanisms.
ORDER PARAMETER DYNAMICS AND COLLECTIVE MODES IN MAGNETIC IMPURITY DOPED SUPERCONDUCTOR

Pair tunnelling has been used to probe the dynamics of the order parameter in the magnetic impurity doped superconductor Al(Er). The results have a bearing on the quantitative validity of the coupled system of equations for the dynamics of the order parameter and the non equilibrium quasiparticle distribution function.
Business Plus Intelligence Plus Technology Equals Business Intelligence

In this article the authors will show how the parallel developments of information technology at the operational business level and decision support concepts progressed through the decades of the twentieth century with only minimal success at strategic application. They will posit that the twin technological developments of the world-wide-web and very inexpensive mass storage provided the environment to facilitate the convergence of business operations and decision support into the strategic application of business intelligence.
Efficient Local Packing in Metallic Glasses

A simple topological model in an earlier manuscript has provided additional support for the concept that efficient atomic packing is a fundamental principle in the formation of metallic glasses. In that work, an approach for defining and quantifying the local packing efficiency, P, was developed for solute-centered clusters that contained only solvent atoms in the first coordination shell. In the present work, this methodology is extended to allow quantification of P when more than one atomic species is present in the first coordination shell. This analysis is applied to several metallic glasses using published experimental data of partial coordination numbers. It is shown that packing in the first coordination shell is generally very efficient, even though the systems studied have significant differences in atomic species, compositions and relative atomic sizes. It is shown that packing is generally efficient around both solute and solvent atom species. Local packing efficiencies much less than unity are expected to be uncommon, since the global average packing efficiency is near unity and local packing efficiencies greater than unity are physically improbable. Deviations from efficiently packed configurations are discussed with respect to the local packing efficiencies in competing crystalline structures and with poorer glass forming ability. The values of P obtained for metallic glasses are essentially identical to the values obtained from a similar analysis of the competing crystalline structures. These results are consistent with frequent earlier reports of topological short range ordering in metallic glasses and with developments that have established the relationship between dense atomic packing and glass formation.
Characteristics of stripping neon ions with carbon foils

Abstract The foil lifetimes, charge state distributions and beam scattering have been measured for the bombardment of 20 μ g/cm 2 carbon foils by 2 and 4 MeV Ne + ions. The charge state distributions and beam scattering agree with previous results. Foil lifetimes of about an hour were obtained.
Risk factors and the prediction of outcome in acquired subglottic stenosis in children.

Abstract Acquired subglottic stenosis in children is caused by damage within the unyielding cricoid ring, usually induced by a tube or instrument. Size of the tube is known to be critical in causing such damage; however, other risk factors including length of time intubated, period of mechanical ventilation and the number of intubations together with the relative skills of those performing the intubations may be of importance. In a series of 37 selected children with a severe stenosis, an unfavorable result of therapy (an aphonic child with an obligate tracheotomy) occurred in 27% of those treated. A minimum 3-year follow-up for the failure group was used. In an effort to predict this unfortunate group, the varied risk factors were studied and analyzed using a computer. The multiple of the risk factors studied termed a risk factor number (R.F.), was applied to the eventual outcome in these children and statistically significant differences were encountered between those who were unable to be decannulated, those who were able to talk around a tracheotomy, and those who had been successfully decannulated. It was found, therefore, that the R.F. number was indeed capable of predicting a successful outcome of therapy in acquired subglottic stenosis, and that the causative factors did indeed contribute to the outcome independent of the type of therapy used. It is suggested that when the multiple of time intubated, time ventilated and number of intubations (R.F. value) exceeds 3 × 103, endoscopic monitoring for laryngotracheal damage be used when an endotracheal tube is in place because of the increased risk of a poor outcome if damage occurs. It is suggested that monitoring on each occasion of the tube being changed in the susceptible group may lead to a predictably lower incidence of subglottic stenosis and an improved prognosis for children requiring prolonged ventilatory support.
The effects of fungal volatile organic compounds on bone marrow stromal cells

Evidence has shown that individuals exposed to indoor toxic molds for extended periods of time have elevated risk of developing numerous respiratory illnesses. It is not clear at the cellular level what impact mold exposure has on the immune system. Herein, we show that 2 fungal volatiles (E)-2-octenal and oct-1-en-3-ol have cytotoxic effects on murine bone marrow stromal cells. To further analyze alterations to the cell, we evaluated the impact these volatile organic compounds have on membrane composition and hence fluidity. Both (E)-2-octenal and oct-1-en-3-ol exposure caused a shift to unsaturated fatty acids and lower cholesterol levels in the membrane. This indicates that the volatile organic compounds under investigation increased membrane fluidity. These vast changes to the cell membrane are known to contribute to the breakdown of normal cell function and possibly lead to death. Since bone marrow stromal cells are vital for the appropriate development and activation of immune cells, this study provides the foundation for understanding the mechanism at a cellular level for how mold exposure can lead to immune-related disease conditions.
Influence of diethanolamine on hard segment ordering in flexible polyurethane foams

In this study the microphase separation and structural organization of the hard segment domains were studied as a function of diethanolamine (DEOA) content for two series of model foams based on toluene diisocyanate (TDI) and glycerol initiated ethylene-oxide-capped propylene-oxide or glycerol initiated propylene-oxide. It was found that as the DEOA content was increased, the more disordered the hard segment domains became. Extractions in dimethyl formamide (DMF) showed that increasing the DEOA content increased the gel fraction, confirming that DEOA further crosslinked the system. More importantly, it was also found that the hard segment domains were also influenced by the DEOA content where the foams lacking DEOA had a much higher level of short range ordering. This was first confirmed by wide-angle x-ray scattering (WAXS) patterns where the amorphous character was much more pronounced as the DEOA content was increased. In addition, Fourier transform infrared (FTIR) data from the carbonyl region showed that the level of bidentate urea or strong hydrogen bonding also decreased as the DEOA content was increased, confirming that the short range ordering does decrease with increased DEOA content. This observation is believed to help explain the greater ease of “plasticization” by temperature and moisture observed of foams that included DEOA in their formulation. This was exemplified by comparing the load relaxation behavior at a low temperature (35°C) and a high temperature (100°C) between two foams varying in DEOA content. At ambient conditions (40°C, 35%RH), the foam with DEOA exhibited slightly higher loads at any given loading time, while at elevated conditions (100°C, 98%RH), there was very little difference between the two foams. Although the observed load relaxation behavior was mostly a result of the increased crosslinking, the increased closed cell content induced by the greater crosslinking also contributed to the load values. © 1997 John Wiley & Sons, Inc. J Appl Polm Sci 65:525–537, 1997
Triptolide abrogates growth of colon cancer and induces cell cycle arrest by inhibiting transcriptional activation of E2F

Despite significant progress in diagnostics and therapeutics, over 50 thousand patients die from colorectal cancer annually. Hence, there is urgent need for new lines of treatment. Triptolide, a natural compound isolated from the Chinese herb Tripterygium wilfordii, is effective against multiple cancers. We have synthesized a water soluble analog of triptolide, named Minnelide, which is currently in phase I trial against pancreatic cancer. The aims of the current study were to evaluate whether triptolide/Minnelide is effective against colorectal cancer and to elucidate the mechanism by which triptolide induces cell death in colorectal cancer. Efficacy of Minnelide was evaluated in subcutaneous xenograft and liver metastasis model of colorectal cancer. For mechanistic studies, colon cancer cell lines HCT116 and HT29 were treated with triptolide and the effect on viability, caspase activation, annexin positivity, lactate dehydrogenase release, and cell cycle progression was evaluated. Effect of triptolide on E2F transcriptional activity, mRNA levels of E2F-dependent genes, E2F1- retinoblastoma protein (Rb) binding, and proteins levels of regulator of G1-S transition was also measured. DNA binding of E2F1 was evaluated by chromatin immunoprecipitation assay. Triptolide decreased colon cancer cell viability in a dose- and time-dependent fashion. Minnelide markedly inhibited the growth of colon cancer in the xenograft and liver metastasis model of colon cancer and more than doubles the median survival of animals with liver metastases from colon cancer. Mechanistically, we demonstrate that at low concentrations triptolide induces apoptotic cell death but at higher concentrations it induces cell cycle arrest. Our data suggest that triptolide is able to induce G1 cell cycle arrest by inhibiting transcriptional activation of E2F1. Our data also show that triptolide downregulates E2F activity by potentially modulating events downstream of DNA binding. Therefore, we conclude that Triptolide and Minnelide are effective against colon cancer in multiple pre-clinical models.
Encapsulation of two aromatics by a carcerand-like capsule of nanometre-scale dimensions

Co-crystallization of C-methylcalix[4]resorcinarene 1 with 4,4′-bipyridine 2 in the presence of nitrobenzene 3 yields a six-component carcerand-like capsule, 2(1)·4(2), held together by 16 hydrogen bonds, in which two molecules of 3 are aligned within the interior of the complex in a head-to-head fashion.
Can salmonids (Oncorhynchus spp.) be identified to species using vertebral morphometrics

Abstract Remains of anadromous Pacific salmon and trout (genus Oncorhynchus ) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook ( Oncorhynchus tshawytscha ), chum ( Oncorhynchus keta ), coho ( Oncorhynchus kisutch ), pink ( Oncorhynchus gorbuscha ), and sockeye salmon ( Oncorhynchus nerka ) and cutthroat ( Oncorhynchus clarki clarki ) and steelhead trout ( Oncorhynchus mykiss ) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000–3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A.
CGRO/OSSE Observations of the Cassiopeia A Supernova Remnant

Cassipeia A, the youngest known supernova remnant in the Galaxy and a strong radio and X-ray source, was observed by OSSE 1992 July 16-August 6. Its close distance (approximately 3 kpc) and its young age (approximately 300 yr) make Cas A the best candidate among known supernova remnants for detecting Ti-44 gamma-ray lines. We find no evidence of emission at 67.9 keV, 78.4 keV, or 1.157 MeV, the three strongest Ti-44 decay lines. From simultaneous fits to the three lines our 99% confidence upper limit to the flux in each line is 5.5 x 10(exp -5) gamma/sq cm s. We also report upper limits for the 4.44 MeV C-12 nuclear de-excitation line, which could be produced by interactions of acclerated particles in the supernova remnant, and for the hard X-ray continuum.
BLOOD ALCOHOL LEVELS IN RATS: NON‐UNIFORM YIELDS FROM INTRAPERITONEAL DOSES BASED ON BODY WEIGHT

Abstract 1 Sprague-Dawley rats (n = 72) weighing from 125 to 450 g were injected intraperitoneally (i.p.) with 16% (w/v) ethanol to provide 1, 2 or 3 g/kg doses. 2 Resulting blood alcohol levels (BALs) demonstrated a general inadequacy of dose/body weight (g/kg) formulations of ethanol to provide uniform BALs in animals of different weights. 3 BAL differences between heavier and lighter rats were not well accounted for by developmental changes in liver weight or alcohol dehydrogenase activity. 4 From the data, a table was derived of more appropriate ethanol injection volumes to produce 0-300 mg% BALs (20 mg% increments) in rats from 100-500 g (10 g increments).
Experimental evidence for density-dependent effects and the importance of algal production in determining population growth rates of riverine zooplankton

Food limitation effects on life history traits of lake zooplankton have been well documented but few studies have examined linkages between population growth rates and food resources in riverine environments. In rivers, allochthonous inputs of particulate organic matter may mitigate food limitation effects allowing density-independent mechanisms associated with washout (discharge) and feeding interference (turbidity) to assume greater importance. We experimentally manipulated densities of commonly occurring riverine zooplankton (Bosmina longirostris and cyclopoid copepods) within 2000 l mesocosms containing ambient or algal-enriched food resources. The experiment was repeated through time (July, August, September) to represent the range of zooplankton densities and food resource levels observed in the Ohio River during warm-water, low-flow conditions. High growth rates and low sensitivity to density-dependent effects were observed during July when particulate organic carbon (POC) and chlorophyll concentrations were highest. Lower growth rates and stronger response to density-dependent effects were observed during August and September experiments when POC and chlorophyll concentrations were lower. Direct manipulations of algal abundance resulted in higher growth rates when gains in chlorophyll were accompanied by increases in the edible size fraction (September experiment). Algal C concentrations were found to be a significant predictor of variation in population growth rates for Bosmina but not cyclopoids. Algal C concentrations in the Ohio River rarely fell below experimentally derived minimum food thresholds but were often below saturation thresholds suggesting that population growth rates were constrained by autochthonous food resources despite the prevalence of allochthonous carbon. Copyright © 2005 John Wiley & Sons, Ltd.
Assessing a Model for Optimal Bus Stop Spacing with High-Resolution Archived Stop-Level Data

With increasing attention given to performance and financial issues related to the operation of public transportation systems, tools are needed to improve the efficiency and effectiveness of service offerings. High-resolution archived stop-level bus performance data can be used to generate and test a bus stop spacing model with the goal of minimizing operating cost while maintaining a high degree of transit accessibility. Two cost components are considered in the spacing model: passenger access cost and in-vehicle passenger stopping cost. These are combined and optimized to minimize total cost. A case study was made of a bus route in Portland, Oregon, by using 1 year of stop-level archived data from the Tri-County Metropolitan Transportation District of Oregon, the regional transit provider of the Portland metropolitan area. The case study indicates that the theoretical optimized bus stop spacing is 1,200 ft, compared with the current value of 950 ft. Trade-offs are discussed, and an estimate is presented of transit operating cost savings based on optimized spacing. It is shown that because of availability of high-resolution archived data, this modeling tool can be applied routinely across multiple routes as part of an ongoing service-planning and performance-measurement process.
Covariant polarization theory of spin-one particles

A covariant theory of polarization effects in the scattering of spin-one particles by spinless targets is developed. The most generally written covariantS-matrix and density matrices ϱ(p) and ϱ′(p′) before and after the scattering, respectively, are split into two parts so as not to mix up the energy states by using the hole-theory condition ofStapp (6). Finally, by substituting the results thus obtained in the scattering equation ϱ′(p′)=Sϱ(p)\(\bar S\), the polarization effects are studied and the corrections to the nonrelativistic theory obtained. A brief discussion of some calculational aids for the spin-one formalism used in this paper is also included because of its pertinence to some nuclear reaction problems.
Prospective optimization of CT under tube current modulation: II. image quality

Despite the significant clinical benefits of computed tomography (CT) in providing diagnostic information for a broad range of diseases, concerns have been raised regarding the potential cancer risk induced by CT radiation exposure. In that regard, optimizing CT protocols and minimizing radiation dose have become the core problem for the CT community. To develop strategies to optimize radiation dose, it is crucial to effectively characterize CT image quality. Such image quality estimates need to be prospective to ensure that optimization can be performed before the scan is initiated. The purpose of this study was to establish a phantombased methodology to predict quantum noise in CT images as a first step in our image quality prediction. Quantum noise was measured using a variable-sized phantom under clinical protocols. The mathematical relationship between noise and water-equivalent-diameter (Dw) was further established. The prediction was achieved by ascribing a noise value to a patient according to the patient’s water-equivalent-diameter. The prediction accuracy was evaluated in anthropomorphic phantoms across a broad range of sizes, anatomy, and reconstruction algorithms. The differences between the measured and predicted noise were within 10% for anthropomorphic phantoms across all sizes and anatomy. This study proposed a practically applicable technique to predict noise in CT images. With a prospective estimation of image quality level, the scanning parameters can then by adjusted to ensure optimized imaging performance.
Flow analysis for the nacelle of an advanced ducted propeller at high angle-of-attack and at cruise with boundary layer control

An axisymmetric panel code and a three dimensional Navier-Stokes code (used as an inviscid Euler code) were verified for low speed, high angle of attack flow conditions. A three dimensional Navier-Stokes code (used as an inviscid code), and an axisymmetric Navier-Stokes code (used as both viscous and inviscid code) were also assessed for high Mach number cruise conditions. The boundary layer calculations were made by using the results from the panel code or Euler calculation. The panel method can predict the internal surface pressure distributions very well if no shock exists. However, only Euler and Navier-Stokes calculations can provide a good prediction of the surface static pressure distribution including the pressure rise across the shock. Because of the high CPU time required for a three dimensional Navier-Stokes calculation, only the axisymmetric Navier-Stokes calculation was considered at cruise conditions. The use of suction and tangential blowing boundary layer control to eliminate the flow separation on the internal surface was demonstrated for low free stream Mach number and high angle of attack cases. The calculation also shows that transition from laminar flow to turbulent flow on the external cowl surface can be delayed by using suction boundary layer control at cruise flow conditions. The results were compared with experimental data where possible.
BROMIDE ADSORPTION INDUCED FORMATION OF THALLIUM BROMIDE ADLAYERS WITH VARYING COMPOSITION AND STRUCTURE ON THE AU(111) ELECTRODE SURFACE

The underpotential deposition of Tl on Au(111) in 0.1 M HClO4 solution containing 1 mM Tl+ and 1 mM Br- has been investigated by using cyclic voltammetry, in situ X-ray scattering, and rotating disk-ring techniques. Three interesting phenomena for the UPD of metals in the presence of adsorbed anions are reported, viz., (i) an increase of the underpotential shift for deposition of Tl on Au(111) in the presence of Br- in solution, (ii) a formation of two mixed adlayers, surface compounds, with the stoichiometry Tl−Br2 and Tl−Br, and (iii) an exceptionally complex structural behavior of this system with five ordered phases. Bromide and thallium form incommensurate rotated-hexagonal close-packed phases at ca. 0.85 and −0.3 V, respectively. In the intermediate potential region three mixed phases exist, identified as 3TlBr2-(√13 × √13), 2TlBr-(3 × √3), and TlBr-c(p × √3).
PTD-mediated Loading of Tumor-Seeking Lymphocytes with Prodrug-Activating Enzymes

Using the approach of peptide transduction domain (PTD)-mediated loading of interleukin-2(IL-2)-activated natural killer (A-NK) cells, tumor-seeking lymphocytes, with prodrug-activating enzymes, we primarily aim to generate a cytotoxic drug selectively within tumors and minimize damage to normal tissues. A-NK cells are able to accumulate selectively at tumor sites. While these cells by themselves possess significant antitumor effect in vivo, we suggest that they can also serve as Trojan horses, by bringing anticancer agents, such as prodrug-activating enzymes, selectively to tumors. We have successfully demonstrated in a mouse model that A-NK cells can be rapidly loaded with prodrug-activating enzymes, such as alkaline phosphatase (AP) and beta-galactosidase (beta-gal), in vitro using enzyme-conjugated peptide PTD5. Upon adoptive transfer into lung-tumor-bearing animals, the loaded A-NK cells are able to bring their cargo of the prodrug-activating enzymes selectively to pulmonary metastases. The targeting of the AP to the tumor tissues is highly specific, since more than a fivefold higher concentration of AP was found in the tumor tissues compared to the surrounding normal lung tissue at 24 h after injection. The approach of transporting prodrug-activating enzymes selectively into tumors clearly shows potential for future targeted chemotherapy. Ongoing studies in our laboratory are evaluating the antitumor efficacy of cellular-dependent enzyme prodrug therapy.
Asymptotic inference for mixture models by using data‐dependent priors

For certain mixture models, improper priors are undesirable because they yield improper posteriors. However, proper priors may be undesirable because they require subjective input. We propose the use of specially chosen data-dependent priors. We show that, in some cases, data-dependent priors are the only priors that produce intervals with second-order correct frequentist coverage. The resulting posterior also has another interpretation: it is the product of a fixed prior and a pseudolikelihood.
Empathy and generalized reciprocity in compliance with requests for help.

This study examined empathy and reciprocity as explanations for why people comply with requests for help. Participants (35 male and 62 female) imagined being asked for money by a person who had locked keys in a car and then reported how likely they would be to comply with such a request, whether they had previously locked their keys in their car (empathy), and, if so, whether they had been helped (reciprocity). In support of the explanation based on empathy, people who reported previously locking their keys in their cars indicated being more likely to comply.
Using hierarchical cluster analysis in nursing research.

This article is a pedagogical piece on hierarchical cluster analysis, a method for investigating the structure underlying data. Such methods are useful for finding similar groups of cases in data sets when it is not known a priori how many groups are present. The article is laid out as follows: First, a brief history and overview of the methods is presented; second, an illustrative example with a small hypothetical data set is used to clarify fundamental concepts; third, hierarchical cluster analysis is applied to a data set from the author’s own program of research to illustrate one way in which the methods may be employed in nursing research; fourth, the limitations of the methods are discussed; and finally, a list of suggested readings, at varying levels of detail, are provided for the interested researcher.
25 Years of ionospheric modification with Space Shuttle OMS burns

The Space Shuttle Orbital Maneuver Subsystem (OMS) is the largest engine to be fired in the F-region ionosphere. The OMS thruster provides 10 kg/s of exhaust materials exiting at a speed of 3 km/s. The OMS nozzle can be pointed in the ram, wake or out-of-plane relative to the Space Shuttle orbit. The vector addition of the exhaust velocity and the orbit velocity provides possible injections speeds of between 4.7 and 10.7 km/s. When the exhaust impacts the ionosphere, neutral-ion collisions and ion-molecule charge exchange yields ions moving at hyper-acoustic speeds. A ten second burn of two OMS engines deposits over 1 Giga-Joule of energy into the upper atmosphere. The ionosphere reacts to an OMS burn by exciting a large number of plasma wave modes including the whistler, fast and slow MHD, Alfven, ion acoustic, lower hybrid, and ion Bernstein waves. These waves have been detected by both radar scatter and in situ electric field plasma probes. Field aligned irregularities are produced by the exhaust interactions. The exhaust pickup ions eventually thermalize with the background atmosphere and they recombine with ambient electrons leaving an electron hole. All these phenomena were obtained first in July 1985 during STS-51F and were detected for the next 25 years through STS-129 with 18 flights of the Space Shuttle. These experiments have demonstrated the (1) Space Shuttle OMS burns can change the HF radio propagation characteristics of the F-layer, (2) artificial ionospheric holes may be used to trigger plasma instabilities that scatter radar and possibly affect GPS propagation, (3) space-based electric field sensors can detect OMS burns in the ionosphere for ranges over 400 km, and (4) optical emissions are produced as the pickup ions recombine with F-region electrons. This type of ionospheric modification has been studied with computer models that employ direct simulation Monte Carlo (DSMC) techniques for the neutral exhaust expansion, plasma fluid theory for the plasma density effects and kinetic theory with Maxwell's equations for the plasma wave generation.
Peak tailing and column radial heterogeneity in linear chromatography

The correlation between the radial heterogeneity of a column and the tailing of the elution profiles of chromatographic peaks was studied using a numerical method. A parabolic distribution of the linear flow velocity of the mobile phase and of the column efficiency in the radial direction were assumed. Moment analysis showed that peak tailing takes place under such experimental conditions and that it increases with increasing range of radial variations of the flow velocity and the column efficiency. It was also found that the higher the column efficiency, the larger the effect of a given degree of radial heterogeneity on the extent of peak tailing. Peak tailing behavior of columns having different efficiencies could be correlated with each other by an equation. Some characteristic features of tailing peaks were analyzed in connection with the column radial heterogeneity.
Inhibition and restoration of hemostasis in the young cardiac surgical patient

For forty years, heparin has been used to temporarily inhibit normal coagulation so as to permit the use of extracorporeal circulation. It has proved effective in preventing gross thrombosis and has not been compromised by changes in adjunctive practices (such as profound hypothermia; circulatory arrest), new pharmacological therapies (such as anesthetics or antibiotics), devices (such as membrane oxygenators), or during use in patients at the extremes of age. Unfortunately, heparin has been and continues to be inefficient in preserving hemostatic function during cardiopulmonary bypass resulting in undesirable bleeding after surgery.
WSB: Current and future trends in frequency generation circuits

In order to adapt to the highly competitive IC market, chip suppliers are racing to reduce the total chip count by integrating many functionalities onto a single IC. However, one of the few elements that escaped this integration and remains to be off-chip is the timing source. In both wireless and wired systems, the reference source requires varying degrees of accuracy and stability over time and temperature. More often these accuracy requirements can only be met by using externally compensated reference sources such as (TCXOS) or (VCXOS), which occupy a large fraction of the board space. Hence a large emphasis is placed on eliminating these components by either integrating their functionality on- chip or replacing them with a much smaller footprint solution. This workshop will review various aspects in the design of stable and low phase noise oscillator circuits. Solutions that are gaining more popularity such as (DCXOS), MEMS and self-referenced oscillators will also be presented.
The relation between nonclassroom contact with faculty and students' perceptions of instructional quality

This study assessed the relationship between the frequency of college students' informal nonclassroom contact with faculty for each of six purposes and their generalized perceptions of instructional quality. Two factorially derived components of instructional quality (based on a 14-item instrument) were used as the dependent variables in two regressions on the six types of contact. The frequency of contacts for discussing intellectual or course-related matters and for discussing a campus issue or problem made statistically significant and unique contributions in predicting students' perceptions of instructor concern and ability.
Density limit in helicon discharges

To produce the highest possible density in a helicon discharge, two helical antennas were used to launch m=+1 waves colliding at the midplane. With 2 kW of RF power on each antenna, a maximum plasma density of was achieved, not much higher than with a single antenna. This density limit is explained by gas depletion, and a method to avoid this is suggested.