cssi/SciSciGPT-SciSciNet huggingface dataset:
Integration of Selected Pharmacologic and Microbiologic Properties of Three New β-Lactam Antibiotics: A Hypothesis for Rational Comparison

To enable the comparison of antibiotics in a standardized, meaningful manner, a system that integrates the pharmacologic and microbiologic properties of beta-lactam antibiotics has been developed. The system compares the duration of time that concentrations of both total and free drug exceed the 90% minimal inhibitory concentration ( MIC90 ) of various pathogens as well as the area under the concentration-time curve for both total and free drug, the latter measurement being an indication of potential for antibiotic diffusion to the periphery. Of the three cephalosporin(-like) compounds evaluated, moxalactam produced the longest duration of free drug above the MIC90 for the Enterobacteriaceae as well as the largest free-drug area under the concentration-time curve following a standardized 2-g intravenous infusion. Both the duration of time cefotaxime was above the MIC90 for the Enterobacteriaceae and the area under the concentration-time curve were significantly less because of its short elimination half-life, results indicating the need for more frequent dosing with cefotaxime than with moxalactam. Cefoperazone, because of its high degree of protein binding and higher MIC90 , develops the least duration of time above the MIC90 for most pathogens. None of these new agents provides free-drug concentrations above the MIC90 for Pseudomonas aeruginosa for longer than 0.6 hr, which suggests that they may be inadequate as single-agent therapy for many serious infections due to this pathogen. Because promotion of comparisons by this method relies on in vitro data for analysis, the conclusions relating to expected clinical efficacy are proffered and should be interpreted with caution.(ABSTRACT TRUNCATED AT 250 WORDS)
Star Tracking through the Exhaust Beam of Mercury Bombardment Thrusters

A 0.5-m focal length, plane grating monochromator is used to measure the radiance of spectral radiation emanating from regions downstream of a mercury bombardment thruster. The wavelength range investigated is 2800-6000 A. This radiation is due primarily to the radiative decay of excited mercury atoms exhausted from the thruster. Radiance values ranged from 10" to 10" w/cm sterad, varying with wavelength. For resonant radiation, the spectral radiance exceeds 10" w/cm sterad. From such radiance measurements, it is concluded that the thruster background radiation should not interfere with the control functions of a star tracker viewing through the thruster exhaust, provided that the tracker is designed to operate with a sufficiently small field of view. Problems may be encountered, however, during the spacecraft acquisition phase where a larger field of view may be required. Here the thruster exhaust radiation may be comparable to the star light flux. This problem may be circumvented by locating the tracker view axis so as not to view downstream of the thruster.
Perioperative blood transfusion in gynecologic oncology surgery: analysis of the National Surgical Quality Improvement Program Database.

Objective To use a large-scale multi-institutional dataset to quantify the prevalence of packed red blood cell transfusions and examine the associations between transfusion and perioperative outcomes in gynecologic cancer surgery.
Empirical evaluation of mutual exclusion algorithms for distributed systems

Abstract Mutual exclusion in distributed memory systems is realized by passing messages among sites to establish a sequence for the waiting sites to enter the critical section. We have evaluated various distributed mutual exclusion algorithms on the IBM SP2 machine and the Intel iPSC /860 system, with their empirical results compared in terms of such criteria as the number of message exchanges and response time. The results take into account the effects of critical section request rate, critical section duration, and system size. Our results indicate that the Star algorithm (1991, M. L. Neilsen and M. Mizuno, in “Proc. 11th Int. Conf. Distributed Computing Systems,” pp. 354–360) achieves the shortest response time in most cases among all the algorithms on a small to medium-sized system, when sites request the critical section many times before involving any barrier synchronization. This is because (1) it requires the exchange of no more than three messages per critical section entry, and (2) contention can quickly be alleviated after several entries into the critical section, if no barrier synchronization is involved in the meantime. On the other hand, if every site enters the critical section only once before encountering a barrier, the improved Ring algorithm (1995, S. S. Fu and N.-F. Tzeng, “Efficient Token-Based Approach to Mutual Exclusion in Distributed Memory Systems,” Tech. Rep. TR-95-8-1, CACS, Univ. Southwestern Louisiana, Lafayette) is found to outperform others under a heavy load; but the Star algorithm and the CSL algorithm (1990, Y. I. Chang, M. Singhal, and M. T. Liu, in “Proc. 1990 Int. Conf. Parallel Processing,” Vol. III, pp. 295–302) prevail when the request rate becomes light. The best solution to mutual exclusion in distributed memory systems is determined by how participating sites generate their mutual exclusion requests.
Inefficient Secretion of Human H27A-Prolactin, a Mutant That Does Not Bind Zn2+

Human PRL binds Zn2+, but the function of the binding is not known. We investigated the effect on PRL production in pituitary cells by obtaining clones of GH4C1 cells stably transfected with human H27A-PRL, a mutant that does not bind Zn2+. Unexpectedly, clones transfected with the mutant human PRL made little rat PRL. Untransfected GH4C1 cells made between 0.5 to 10 microg rat PRL/10(5) cells in 24 h. Clones transfected with vector alone (four of four), wild type human PRL (six of six), or with human K69A-PRL (two of two) made amounts of rat PRL in the same range. Clones transfected with human H27A-PRL (five of five) made 0.003-0.1 microg rat PRL/10(5) cells in 24 h, and the production of rat PRL mRNA was reduced. Human H27A-PRL was not efficiently secreted; 20-40% newly synthesized H27A-PRL was degraded by 60 min, and there was usually a delay in release of newly synthesized H27A-PRL. Reduction of rat PRL production is not mediated through the PRL receptor, because no sequences for the receptor in GH4C1 cells were detected by RT-PCR. Proteins involved in folding, such as BiP, were not specifically elevated in the H27A-PRL clones. In transient transfections, in which cells have not undergone selection, we found no evidence for disulfide-bonded aggregates of the mutant protein. The results indicate that Zn2+ binding stabilizes PRL in the secretory pathway; the instablility of the mutant protein may trigger effects that suppress rat PRL production directly or that indirectly result in selection of clones with low rat PRL production.
An industry model of commodity chemicals from renewable resources

Abstract A systems model based on linear programming has been constructed for a commodity chemicals industry using renewable resources and coal, as well as gas and petroleum-derived resources. The results suggest that coal should precede biomass as a feedstock in the event of a significant reduction in the use of gas and petroleum-based feedstocks. However, a reasonable approximation to the current product slate for the petrochemical industry could be manufactured using only renewable resources for feedstocks. Use of the chemicals industry model to evaluate process technologies is demonstrated. Conceptual hypothetical technologies and improvements to existing technologies are considered in the context of input to program planning for research and development.
Lower Temperature Si Thin Films by Metal Induced Growth for Lower Cost Solar Cells

Metal induced growth (MIG) was used to form epitaxial thin films of microcrystalline Si (μc-Si). By substituting Al as the catalyst metal in place of the usual Ni, x-ray diffraction (XRD) confirmed that μc-Si was successfully grown at temperatures between 350-525°C. At 525°C, a preferred orientation of (220) Si was observed with additional (111) and (311) Si orientations, while a temperature of 350°C resulted in a shift in preferred orientation to (111) Si. The lower limit for Al thickness was found to be between 10-20 nm with little crystallization and a smooth surface observed at 10 nm with XRD and SEM, respectively. Electrical measurements on Schottky diodes revealed space-charge limited conduction (SCLC) with an exponential distribution of trap levels due to diffusion of Al atoms into the Si, which was supported by analysis with energy dispersive x-ray spectroscopy (EDX) near the film surface. By depositing a thin layer of Co on top of Al prior to sputtering, the films exhibited increased crystallinity and a more uniform surface likely due to increased confinement of Al atoms. Electrical measurements demonstrated a shift from SCLC to thermionic emission in resulting Schottky diodes.
Centrally patterned rhythmic activity integrated by a peripheral circuit linking multiple oscillators

The central pattern generator for heartbeat in the medicinal leech, Hirudo generates rhythmic activity conveyed by heart excitor motor neurons in segments 3–18 to coordinate the bilateral tubular hearts and side vessels. We focus on behavior and the influence of previously un-described peripheral nerve circuitry. Extracellular recordings from the valve junction (VJ) where afferent vessels join the heart tube were combined with optical recording of contractions. Action potential bursts at VJs occurred in advance of heart tube and afferent vessel contractions. Transections of nerves were performed to reduce the output of the central pattern generator reaching the heart tube. Muscle contractions persisted but with a less regular rhythm despite normal central pattern generator rhythmicity. With no connections between the central pattern generator and heart tube, a much slower rhythm became manifest. Heart excitor neuron recordings showed that peripheral activity might contribute to the disruption of centrally entrained contractions. In the model presented, peripheral activity would normally modify the activity actually reaching the muscle. We also propose that the fundamental efferent unit is not a single heart excitor neuron, but rather is a functionally defined unit of about three adjacent motor neurons and the peripheral assembly of coupled peripheral oscillators.
Growth to age 3 years among very low-birth-weight sequelae-free survivors of modern neonatal intensive care.

6. Enhorning G, Grossman G, Robertson B: Tracheal deposition of surfactant before the first breath, Am Rev Respir Dis 107:921, 1973. 7. Fujiwara T, Chida S, Watabe Y, Maeta H, Morita T, and Abe T: Artificial surfactant therapy in hyaline membrane disease, Lancet 1:55, 1980. 8. King R J, and Clements JA: Surface active materials from dog lung. !L Composition and physiologic correlations, Am J Physiot 223:715, t 972. 9. Hallm'an M, Schneider HA, and Gluck L: Human fetus, a potential surfactant donor: isolation of lung surfactant from amniotic fluid, Pediatr Res 15:663, 1981. 10. Pearson D J, Mentnech MS, Gamble M, Taylor G, and Green FHY: Acute pulmonary injury induced by immune complexes, Exp Lung Res 1:323, 1'980. 11. King RJ and Macbeth MC: Physicochemical properties of dipalmitoyl phosphatidylcholine after interaction with an apolipoprotein of pulmonary surfactant, Biochim Biophys Acta 557:86, 1979.
Symmetry between absorption and amplification in disordered media

We address the issue of whether amplification, like absorption, suppresses wave transmission at large gain, as has been claimed in previous studies of wave propagation in active random media. A closer examination reveals that the paradoxical symmetry between absorption and amplification is an artifact of unphysical solutions from the time-independent wave equation. Solutions from the time-dependent equation demonstrate clearly that when gain is above the threshold, the amplitude of both the transmitted and the reflected wave actually increases with time, apparently without bound. The implications of the current finding is discussed.
Physiology of feeding in miniature pigs

The anatomy and physiology of feeding in miniature swine were studied, using gross dissection, electromyography, cinematography, and cineradiography. Small particles are preferred for ingestion, and large items are usually broken down outside of the oral cavity. The particles are initially picked up with the lower lip and then retrieved by the tongue; the tongue very rarely leaves the oral cavity. Geniohyoid, mylohyoid and digastric are the most active muscles during food collection. Mastication is fairly rapid (3 cycles/sec) and involves a transverse component which may be either medially or laterally directed. The direction of motion is generally reversed with every chew. Electromyography indicates that the transverse rotation is caused by a force couple consisting of protrusors (masseter, medial and lateral pterygoids) on one side and retrusors (zygomaticomandibularis and temporalis) on the other. The direction of the rotation is not necessarily related to the side containing the bolus. Mandibular depression is electromyographically biphasic. Concurrent tongue and hyoid movements complicate the interpretation of activity patterns in the oral floor. Both masticated food and liquid are stored between the tongue and the soft palate and epiglottis before being swallowed. Swallowing involves very strong activity in all of the hyoid and tongue muscles and very low activity in the adductors. Liquid is taken in by suction rather than lapping. Comparisons with other mammals are presented.
Photonic and plasmonic modulators based on optical switching in VO2

Researchers all over the world are competing in a technology-driven quest to develop the next generation of ultrasmall, low-power photonic and plasmonic devices. One route to this objective involves hybrid structures that incorporate a phase-changing material into the structure, creating a nanocomposite material in which the optical response of a plasmonic or photonic structure is modulated by a change in phase, crystallinity or dielectric function induced by thermal, optical or electrical stimulus. Vanadium dioxide (VO 2) has been considered as a potential electro-optic switching material for electronic and photonic applications ever since its semiconductor-to-metal transition (SMT) was first described half a century ago. This review describes the application of vanadium dioxide as the switching element in (i) a hybrid silicon ring resonator and (ii) a polarization-sensitive, multifunctional plasmonic modulator in the form of a nanoscale heterodimer. As is now widely known, the SMT in VO 2 is also accompanied by a structural phase transition (SPT) from the M1 (monoclinic) to a rutile (tetragonal, R) crystalline form that was believed to prevent a fast recovery after switching. However, recent research has shown that this picture is oversimplified, and that there is a monoclinic metallic state that enables true ultrafast switching. That understanding, in turn, is leading to new concepts in developing hybrid nanocomposites that incorporate VO 2 in silicon photonics and plasmonic modulators, enabling the construction of ultrafast optical switches, modulators and memory elements.
The cole midfoot osteotomy: a retrospective review of 11 procedures in 8 patients

This article presents the results of a retrospective chart and radiographic review of 11 feet (8 patients) that underwent a Cole midfoot osteotomy from February 1998 through October 2000 at the Western Pennsylvania Hospital. The average time to follow-up was 23 months (range, 11 to 29.5 months). A 100% bony union rate was achieved, with an average time to radiographic union of 2.3 months (range, 1.2 to 4.5 months). The average time until full weightbearing was 3.3 months (range, 2 to 4.25 months). The average preoperative talo-first metatarsal angle on an anteroposterior radiograph was 8.60° and 8.64° on the lateral radiograph. The average postoperative change was 3.50° (P = .03) on the anteroposterior radiograph and 16.82° (P = .003) on the lateral radiograph. At the final follow-up visit, all patients were independently active and were able to wear conventional shoe gear. A postoperative questionnaire was completed by 5 of 8 patients (8 of 11 feet) at a mean 21 months (range, 13 to 29.5 months) postoperatively. Of these patients, 4 of 5 patients (7 of 8 feet) would recommend this surgery to others. No major complications were reported in this study. These results suggest that the Cole midfoot osteotomy is a reasonable procedure to consider for correcting pes cavus deformities with the apex in the midfoot.
Advances in the neuropharmacology of Parkinsonism.

Abstract Advances through basic research have elucidated the disturbances of neurotransmitter function in Parkinson's disease, with findings directly applicable to drug therapy. Dopamine has replac...
Methanol Toxicity: Treatment With Folic Acid and 5‐Formyl Tetrahydrofolic Acid

After methanol administration to monkeys, an accumulation of formate in blood occurs coincident with the development of metabolic acidosis and a depletion of blood bicarbonate. Formate metabolism in monkeys depends upon and is regulated by a folate-dependent system; therefore, the effect of folic acid pretreatment and 5-formyl tetrahydrofolic acid administration on methanol toxicity was investigated. Treatment of monkeys with repetitive doses of either sodium folate (48, 24, 12, and 4 hr prior to methanol) or 5-formyl tetrahydrofolic acid (2 mg/kg at 0, 4, 8, 12, and 18 hr after methanol) resulted in a marked decrease in the levels of blood formate and an absence of both metabolic acidosis and depletion of blood bicarbonate following methanol administration. Also, 5-formyl tetrahydrofolic acid reversed methanol toxicity once it was established in the monkey. The results indicate that folate compounds decrease formate accumulation after methanol by stimulating formate oxidation or utilization and suggest a possible use for folates in the treatment of certain cases of human methanol poisoning.
Voices in the outer room.

SUMMARY An argument (in the form of a demonstration) for the development of a queer aesthetic, the essay asks whether it is our charge as lesbian writers to hold a mirror up to our experience, to "self-disclose" (so often such narratives change nothing but succeed in flattening our lives), or to find the form that will answer to queer habits of being, radical sensibilities and ideologies. The essay takes three different liminal spaces as its ground-a sickroom, a conversation on an airplane, and a Catholic confessional-to explore my own aesthetic process, the role played by randomness and interruption in that process, the complex presence of external and internalized (dis)embodied voices in my self-writing, and the desire through my work to create what I call "disruptive beauty."
Handheld rectilinear ion trap mass spectrometer.

A shoebox-sized, 10-kg, handheld mass spectrometer, Mini 10, based on a rectilinear ion trap mass analyzer has been designed, built, and characterized. This instrument has evolved from a decade-long experimental and simulation program in mass spectrometer miniaturization. The rectilinear ion trap has a simplified geometry and high trapping capacity, and when used with a miniature and ruggedized pumping system, it allows chemical analysis while the instrument is being carried. Compact electronics, including an air core RF drive coil, were developed to control the instrument and to record mass spectra. The instrument runs on battery power, consuming less than 70 W, similar to a laptop computer. Wired and wireless networking capabilities are implemented. The instrument gives unit resolution and a mass range of over m/z 500. Tandem mass spectrometry capabilities are implemented using collision-induced dissociation, and they are used to provide confirmation of chemical structure during in situ analysis. Contin...
Transcriptional control within the three-dimensional context of nuclear architecture: requirements for boundaries and direction.

Evidence is accruing that the architectural organization of nucleic acids and regulatory proteins within the cell nucleus support functional interrelationships between nuclear structure and gene expression. The punctate distribution of several transcription factors has provided several paradigms for pursuing mechanisms that direct these regulatory proteins to subnuclear sites where gene activation or suppression occurs. Sequences that are necessary and sufficient to direct regulatory proteins to transcriptionally active nuclear domains have been identified. Mutations that disrupt intranuclear targeting signals lead to modified subnuclear distribution of transcription factors and aberrant expression in tumor cells. J. Cell. Biochem. Suppls. 32/33:24-31, 1999.
The Relationship between Extreme Hourly Precipitation and Surface Temperature in Different Hydroclimatic Regions of the United States

Abstract In a changing climate, there is an interest in predicting how extreme rainfall events may change. Using historical records, several recent papers have evaluated whether high-intensity precipitation scales with temperature in accordance with the Clausius–Clapeyron (C–C) relationship. For varying locations in Europe, these papers have identified both super C–C relationships as well as a breakdown of the C–C relationship under dry conditions. In this paper, a similar analysis is carried out for the United States using data from 14 weather stations clustered in four different hydroclimatic regions: the coastal northeast, interior New York, the central plains, and the western plains. In all regions except interior New York state, 99th percentile 1-h precipitation generally followed the C–C relation. In interior New York, there was evidence that intensity scaled with a super C–C relationship. For the 99.9th percentile precipitation, interior New York displayed some moderate evidence of a super C–C rela...
Plasmon-waveguide resonance spectroscopy applied to three potential drug targets: cyclooxygenase-2, hepatitis C virus RNA polymerase and integrin αVβ3

Plasmon-waveguide resonance (PWR) spectroscopy has been used to study the interactions between ligands that correspond to inhibitors, activators or substrates and three integral membrane proteins representing potential drug targets; cyclooxygenases 1 and 2 (COX-1 and -2), integrin alphaVbeta3, and hepatitis C virus RNA polymerase. The proteins were incorporated into an egg phosphatidylcholine bilayer deposited onto the surface of the PWR resonator, and changes in the amplitude and position of the PWR spectra due to mass density increases and conformational transitions have been used to characterize the kinetics and binding affinities corresponding to these interactions. Although the partition of COX-2 into the bilayer was not as efficient as was the case with the other two proteins, sufficient protein could be incorporated to allow ligand binding to be observed. It was also possible to incorporate COX-1 into a lipid bilayer by adding a suspension of microsomal membrane fragments containing this enzyme to a preformed bilayer, and to observe binding of an inhibitory ligand. The interactions between integrin alphaVbeta3 and two ligands with different in vivo efficacies could be distinguished by both spectral measurements and binding kinetics. In the case of the RNA polymerase, the kinetics of PWR spectral changes upon adding a substrate solution to an enzyme-template complex were consistent with those obtained from direct measurements of enzymatic turnover. These experiments demonstrate the utility of PWR spectroscopy to provide novel information regarding drug interactions with membrane proteins in a lipid environment and to distinguish conformational changes induced by binding of various drug molecules.
Possible involvement of lipid peroxidation in salicylic acid-mediated induction of PR-1 gene expression

Abstract Salicylic acid (SA) is a natural signal molecule which plays an important role in plant defense responses against pathogen infection. Previous work has demonstrated that catalase may be involved in the mechanism of SA action. Recently, SA has been shown to inhibit catalase by serving as a one electron-donating substrate for its peroxidative reaction. One of the likely by-products of this interaction is a SA free radical. Since free radicals are potent inducers of lipid peroxidation, SA and its analogues were tested for their ability to induce lipid peroxidation in tobacco cell cultures. SA and its biologically active analogues, which increase PR gene expression, enhance disease resistance and also inhibit catalase, induced accumulation of lipid peroxidation products. Inactive analogues did not. Exogenous application of lipid peroxides induced PR-1 gene expression. Furthermore, the induction of PR-1 genes by SA was inhibited by diethyldithiocarbamic acid, a compound that converts lipid peroxides into their hydroxyl derivatives. We suggest that the induction of lipid peroxidation by a SA radical may be involved in the action of SA and that one or more of the lipid peroxidation products may mediate signal transduction leading to PR-1 expression.
Application of general variational methods with discontinuous fields to bending, buckling, and vibration of beams

Abstract The effectiveness of consistent variational statements for discontinuous fields is illustrated for bending, buckling, and vibration of elastic beams. General variational statements are developed, from which finite-element formulations with piece-wise constant and piece-wise linear trial functions, are obtained. Results are illustrated by means of numerical examples.
Giant magnetoelectric effect in the J eff = 1 2 Mott insulator Sr 2 IrO 4

Our magnetic, electrical, and thermal measurements on single crystals of the ${J}_{\mathrm{eff}}=1/2$ Mott insulator, ${\text{Sr}}_{2}{\text{IrO}}_{4}$, reveal a giant magnetoelectric effect (GME) arising from a frustrated magnetic/ferroelectric state whose signatures are: (1) a strongly enhanced electric permittivity that peaks near an observed magnetic anomaly at 100 K, and (2) a large $(\ensuremath{\sim}100%)$ magnetodielectric shift that occurs near a metamagnetic transition. The GME hinges on a spin-orbit gapping of $5d$ bands rather than the magnitude and spatial dependence of magnetization, as traditionally accepted.
A systematic algorithm for the management of lower lip asymmetry.

Abstract Purpose An asymmetric smile, caused by loss of function of the lip depressors, can be functionally and cosmetically debilitating. Although some surgeons report excellent results with muscle transfer to the lower lip, many facial reanimation surgeons find that dynamic techniques do not consistently address the lower lip. Our objectives were to retrospectively review our outcomes after treatment of the asymmetric lower lip, and to propose a progressive, stepwise algorithm for the management of lower lip asymmetry in facial paralysis. Material/Methods Retrospective chart review was performed on all patients treated in a multidisciplinary facial nerve center with lower lip asymmetry over an eighteen month period. Treatment ranged from a temporary trial of lidocaine, to chemodenervation with botulinum toxin, to pedicled digastric muscle transfer, and/or resection of the nonparetic depressor labii inferioris (DLI). Results Fifty-seven patients were treated with chemodenervation with botulinum toxin, four with anterior belly of the digastric transfer, and 3 with DLI resection. All patients with DLI resection had undergone chemodenervation to the contralateral lower lip with botulinum toxin and were pleased with the appearance of their smile. Conclusions We have found that lower lip asymmetry is optimally managed by adherence to a standardized protocol that offers patients insight into the likely outcome of chemodenervation or surgery and progresses systematically from the reversible to the irreversible. We present our algorithm for the management of the asymmetric lower lip, which reflects this graduated approach and has resulted in high patient satisfaction.
Bootstrapping demand and supply elasticities: The Indian case

Abstract We discuss bootstrap confidence intervals for short-run and long-run demand and supply elasticities for imports and exports. We use Koshal, Shukla and Koirla's (1992) simultaneous equation demand and supply model for Indian exports based on 1960–1986 data. Although the long run price elasticity of supply is large, (about 25) and significant, the asymptotic as well as bootstrap confidence intervals remain wide. Hence price reduction by devaluation of Indian Rupee alone may not have been enough to spur the major export growth experienced in the early 1990s. We discuss the potential uses of relatively simple bootstrap methods in the context of the delta method for standard errors of long run elasticities, pivoting transform, nonlinearities and nonnormality. ( JEL F14, C12, CIS, C30)
A Volatile Public: The 2009 Whole Foods Boycott on Facebook

The 2009 “Boycott Whole Foods” campaign was born on Facebook in response to criticism by Whole Foods CEO John Mackey of the Obama administration's proposed health-care reforms. The boycott demonstrates volatile collective action through heterogeneous and heterarchic encounters, characterized by the formation of a collective across geographical distance, vibrant interaction across political distance, and temporary presence. These features suggest the possibility of further activism by the middle class on shared ethical issues, and of unintended yet forceful consequences of activism on social media. Despite widespread concern about group polarization in cyberspace, social media also offer a space in which enclaves encounter opponents and subject their ideas to scrutiny.
Class A type II scavenger receptor mediates silica-induced apoptosis in Chinese hamster ovary cell line.

Macrophage scavenger receptors are known to bind endotoxins, oxidized low-density lipoproteins (Ox-LDL), and other proteins with clustered negative charges. Recent evidence indicates some particulates may also bind to the scavenger receptor and initiate apoptosis. In this study, chinese hamster ovary (CHO) cells stabily transfected with the murine class A type II scavenger receptor (SR-A II) were exposed to crystalline silica to examine the role of this receptor in apoptosis. In a 24-h culture, silica (250 μg/ml) induced significant cell injury (necrosis and apoptosis) in transfected cells (MSR II) but not in the control cells (KA-7). This effect was specific to silica, as a control particle titanium dioxide had no cytotoxic effects on the MSR II cells at equal particle mass concentrations. Furthermore, silica-induced apoptosis in the MSR II cells could be eliminated by preincubating the cells with SR-A II antagonists: polyinosinic acid or maleylated bovine serum albumin. This study further supports the hypothesis that the SR-A II is directly involved with silica toxicity and that certain scavenger receptor ligands may have an important role in regulating macrophage apoptosis.
Ensuring Accountability in Human Services Contracting Can Stewardship Theory Fill the Bill

Stewardship theories have been proposed as a basis for the reform of roles and responsibilities of principals and agents in government-contracted service relations and for the development of effective methods for ensuring accountability (and quality) in contracted human services. This article reports on an empirical field study that assessed the utility of external control methods derived from principal-agent theories and used to ensure accountability in contracted services. Assessments were based on evaluations provided by government case managers and caregiver employees in service-providing organizations. The article considers whether methods derived from stewardship theory could replace or supplement external control methods when they fail to uphold accountability or when accountability gaps exist. The author argues that methods derived from stewardship theories could fill some accountability gaps, but systemic problems in contracted human services must also be addressed. Additional research on steward...
Leaving home, returning home: Migration as a labor market choice for Alaska Natives

We investigate determinants of the pattern of recent migration of Alaska Natives between rural homelands and urban areas. A review of the literature on moving in the North American North suggests that economic opportunities draw migrants, although such opportunities must be viewed in the context of the mixed subsistence-cash economy prevailing in rural areas of the region. Consequently, we model Native migration as a simultaneous decision with labor market participation in a mixed economy. Estimated equations explaining individual Alaska Native migration choices using the U.S. Census Public Use Microdata Sample (PUMS) are consistent with the model, and also suggest that perceived opportunities differ between women and men.
Welfare reform and the child welfare system

Over the past decade, the US welfare system has undergone a major transformation. How has welfare reform affected children and families, and the child welfare system? This paper provides an overview of welfare reform and its effects on children and families. It then reviews the reasons that there might be links between welfare reform and the child welfare system and the evidence on these links. The paper concludes with suggestions for further research.
Suppression of Pressure Oscillations in High-Mach-Number, Turbulent, Cavity Flow

Fluctuating wall pressure measurements have been made in a high-Reynolds-number, Mach 5, turbulent cavity flow. The cavity length to depth ratio was varied from 3 to 5 with a fixed width to depth ratio of 3. Slotted and vented upstream and downstream walls, slanted downstream walls (inclined in either the streamwise direction only or inclined streamwise and swept spanwise), and spoiler and vortex generator arrangements were used to explore their effectiveness at suppressing the pressure oscillations. In practice, wall geometry will be dictated by many constraints; thus, in the absence of a particular application, it is not meaningful to claim that one particular geometry is the most effective. However, consistent with work at lower Mach numbers, it is evident that certain slanted and swept downstream walls are quite effective, reducing the high mean pressure and rms pressure levels near the downstream wall/floor junction by 30-35% and 40%, respectively. At this high Mach number, the coupling between the shear layer dynamics and cavity acoustics is weak. As a consequence, the cavity mode frequencies, which are essentially independent of geometry changes, are in as good an agreement with closed-box frequency predictions as they are with the predictions of Rossiter's modified formula (Rossiter, J. E., Wind Tunnel Experiments on the Flow over Rectangular Cavities at Subsonic and Transonic Speeds, Aeronautical Research Council Reports and Memoranda, ARCR & M No. 3438, London, 1964).
Lack of suppression of lymphocyte MIF production by estradiol, progesterone and human chorionic gonadotropin

Abstract The hypothesis that hormones produced by the placenta contribute to immunosuppression during pregnancy is an attractive one. In order partially to evaluate this hypothesis, we utilized the Migration Inhibition Factor (MIF) Assay, which is an in vitro model of delayed hypersensitivity in that presensitized lymphocytes stimulated by antigen release a glycoprotein (MIF) which inhibits the normal migration of macrophages. The effect of placental hormones on this model of cellular immunity was tested using the direct and indirect MIF assays in pre-immunized guinea pigs. Estradiol (1–50 μg/ml), progesterone (1–50 μg/ml) and commercial grade or chromatography-purified hCG (1000–5000 IU/ml) did not affect normal macrophage migration and also failed to suppress production of MIF by guinea pig lymphocytes stimulated with antigen. None of the hormones either enhanced or suppressed macrophage response to preformed MIF. The results indicate that these hormones do not suppress lymphocyte reactivity as assessed by the production of lymphokines or the target cell response to the mediator. The reported effects of steroid hormones and crude hCG on other models of cellular immunity are discussed.
Hamilton Decompositions of Certain 6-regular Cayley Graphs on Abelian Groups with a Cyclic Subgroup of Index Two

Abstract Alspach conjectured that every connected Cayley graph of even valency on a finite Abelian group is Hamilton-decomposable. Using some techniques of Liu, this article shows that if A is an Abelian group of even order with a generating set { a , b } , and A contains a subgroup of index two, generated by c , then the 6 -regular Cayley graph Cay ( A ; { a , b , c } ⋆ ) is Hamilton-decomposable.
Probabilistic models of project management with design implications

As project management has come of age, there has been an increasing awareness of the fact that the greater the inherent difficulty of the R&D activity, the more likely it becomes that the project will encounter cost and schedule overruns. Some authors have even gone so far as to call for `built-in' allowances for overruns. It is the purpose of this paper to point out not only that such a scheme is necessary, but also to show the magnitude of the required allowances and their sensitivity to the distribution of risk associated with the project.
Tomographic In Version For Velocity Plus Statics

Another problem with borehole tomography has to do with uneven ray coverage. It is well known that when the tomogram is parameterized into rectangular cells, parts of the model are well constrained, while others (particularly the bottom) an not. For this reason, the linear system describing the experiment is ill-conditioned. An infinite number of velocity distributions exist all of which fit the traveltime residuals equally well. If we want to add statics to the set of unknowns, the solution uncertainty increases. If we then want to solve the system by least-squares, some sort of damping is required to insure stability.
Glycosyltransferases as cell adhesion molecules.

Abstract Specific glycosyltransferases are believed to be present on the cell surface, where they may function as cell adhesion molecules by binding oligosaccharide substrates on adjacent cell surfaces or in the extracellular matrix. The best studied of these is β1,4-galactosyltransferase, which mediates sperm binding to the egg coat and selected cell interactions with the basal lamina. Molecular models have recently been presented to account for the expression of β1,4-galactosyltransferase on the cell surface, thus enabling one to alter its surface expression and to examine the consequences on fertilization and development.
The complete nucleotide sequence of the multi-drug resistance-encoding IncL/M plasmid pACM1.

Abstract The 89,977 bp nucleotide sequence of pACM1, isolated from a 1993 outbreak strain of cephalosporin-resistant Klebsiella oxytoca, has been completed and assigned GenBank accession number KJ541681. The plasmid has a single 31,842 bp mosaic multi-drug resistance-encoding (MDR) region comprising the mer resistance module of Tn1696, two integrons with a total of seven cassettes, one complete copy each of IS1R and IS26, and the bla(SHV-5)-carrying Tn2003 (with defective IS26 termini), all within a Tn1721-like element inserted into the mucB gene of the IncL/M plasmid backbone. The Tn1721–Tn1696 combination resembles sequence found in the chromosomal MDR islands of some Acinetobacter baumannii isolates. Among the completely sequenced IncL/M resistance plasmids, the Tn1721-based MDR region is unique, but data from older studies suggest that this type of plasmid was widespread in the 1990s. Since resistance gene dosage is affected by plasmid copy number (PCN), we used a relatively simple new “efficiency-corrected” qPCR assay to measure the PCN of pACM1. There are approximately three copies per chromosome in an Escherichia coli DH5α host, and two in the original Klebsiella oxytoca isolate. We could not find similar PCN data for other medically important plasmids for comparison. The study of this plasmid property and its effect on resistance levels should be facilitated in the future by the availability of qPCR instruments and complete genome sequences.
Peabody Picture Vocabulary Test: Comments on Administration and Two Methods of Scoring:

Two methods of scoring the Peabody Picture Vocabulary Test exist. One deducts credit for all errors above the lowest basal. The second and correct method deducts credit for errors above the highest basal and gives no credit for responses above the lowest ceiling. The Form A was given to 1,885 5-, 876 9-, 837 10-, and 816 11-yr.-old participants in the Child Health and Development Studies of Oakland, California. 45% of these children had multiple basals causing their scores to differ from 1 to 19 points by method of grading used. Means and standard deviations of the raw scores and IQs by age and method of scoring are presented and demonstrate that one consistent method of grading must be used to obtain valid results. The unexpected high frequency of multiple basals is due to the increase over the past 15 yr. in verbal abilities of average children and the currently extreme difficulty of several questions relative to their placement in the test.
Cooperative control of uncertain multivehicle systems

In this paper, we present a cooperative control architecture for high-order multivehicle systems having non-identical nonlinear uncertain dynamics. For each vehicle, the proposed methodology consists of a local cooperative controller and a vehicle-level controller. The former controller receives the relative output measurements of the neighboring vehicles in order to solve a containment problem formulated on a leader-follower framework. In particular, the leaders generate a trajectory in which the vehicles (followers) converge to the convex hull formed by those of the leaders. For a special case with one leader, this controller synchronizes the output of the vehicles with the output of the leader. The latter controller receives the internal state measurements for suppressing the nonlinear uncertain dynamics of the vehicle by using a decentralized robust adaptive control approach. The interaction topology between vehicles is described by undirected graphs, and extensions to directed graphs are further discussed.
Relay with Side Information

This paper establishes necessary and sufficient conditions for reliable transmission of a source over a relay channel when source side information is available non-causally (a) only at the receiver, (b) only at the relay, or (c) at both the relay and the receiver. For the cases of side information only at the receiver and at both the relay and the receiver, we establish tight necessary and sufficient conditions that apply to any relay channel and show that source-channel separation is optimal. When side information is available only at the relay, we establish a necessary condition for reliable transmission and show that it is tight for the class of degraded relay channels and that source-channel separation is optimal in this case.
Infant emotion and the vocal affect lexicon

The role of the vocal channel of emotion expression in infancy has been neglected in developmental theory. The present review describes the ontogenetic course of vocal emotional expression as exhibited by human and infrahuman primate young and considers its dynamic relationship to the facial and bodily components of expression. The infant's encoding of negative and positive emotion expression is discussed within a developmental framework. In addition, this review assesses the impact of early social influences. It is concluded that early patterns of infant vocal emotional expression are probably biogenetically determined and that there may be certain universal vocal signals. However, data derived from studies of dyadic interaction indicate that the transition from raw affect expression in early infancy to a more modulated pattern later on is a product not only of neuromuscular maturation but of maternal coaching in affective expression as well.
Mobile antenna characterization and optimization for uhf satellite communications

Abstract An Improved Lightweight Satellite Communications Antenna (ILSA) was characterized by simulation and measurement. The measured gain is within 1.1 dB of the simulated gain and the measured beamwidths and sidelobe levels are in excellent agreement with the simulations. In addition, various antenna geometries that represent both damaged and incorrectly deployed operating conditions were also measured and simulated. Finally, an optimized array geometry is presented that provides improved antenna performance.
Revisiting the Component Additive Method for light‐frame walls protected by gypsum board

The National Building Code of Canada provides architects, engineers and builders with a simple, practical calculation method for assigning fire-resistance ratings to wood-frame and steel-frame wall, floor and roof-ceiling assemblies. It was originally devised in the early 1960s and is commonly known as the Component Additive Method (CAM). A collaborative industry–government research program was carried out recently at the National Research Council Canada to develop new fire-resistance ratings for gypsum-board protected walls. Forintek Canada Corp. and the Canadian Wood Council participated in that program on behalf of Canada's wood industry. As part of the research program, a number of full-size fire-endurance tests were carried out on wood-frame and steel-frame walls. The results of those fire tests have allowed us to revisit those sections of the Component Additive Method which are applicable to light-frame walls lined with gypsum board. © 1997 John Wiley & Sons, Ltd.
Distribution and proportion

L'A. defend le concept aristotelicien de distribution contre les critiques de P. Geach, en developpant l'application qu'en fait R. Carnes dans un article recent. L'A. applique la distribution a une quantite k de systemes syllogistiques fractionnaires et de systemes proportionnels avec un nombre infini de quantites
Typical Symptoms and Atypical Radiographic Findings in a Case of Chronic Eosinophilic Pneumonia

Chronic eosinophilic pneumonia is an idiopathic pro-cess marked by eosinophil infiltration of the lungs, whichusually occurs in association with peripheral eosinophilia.The radiographic pattern typically seen in this disorder isbilateral peripheral infiltrates with hilar sparing, and it hasbeendescribedasthe“radiographicnegativeofpulmonaryedema.” We describe the case of a 41-year-old womanwho presented with typical symptoms and laboratory fea-tures of the disease, but a highly atypical radiographicpattern, marked by dense unilateral consolidation and shiftof the mediastinal structures to the affected side.
Cognitive Processing of Self-Report Items in Educational Research: Do They Think What We Mean?

Techniques emerging from the considerable research on cognitive aspects of survey methodology include various forms of probing and cognitive interviewing. These techniques are used to examine whether respondents' interpretations of self-report items are consistent with researchers' assumptions and intended meanings given the constructs the items are designed to measure. However, although informal procedures are common, such developments have not been systematically applied in educational research. We describe how information derived from the systematic application of cognitive pretesting can contribute to determining the validity—designated cognitive validity—of self-report items. Examples are presented from prominent motivation-related instruments that assess real-world instructional practices, mastery classroom goal structure, and student self-efficacy. The implications and pragmatics of adopting this approach are discussed.