cssi/SciSciGPT-SciSciNet huggingface dataset:
Counterion effects in intramolecular charge transfer in radical anions

The influence of the presence of an electrolyte in a low-polarity solvent (tetrahydrofuran) on the rate of a weakly exoergic ([approx]50 meV) nonadiabatic intramolecular charge shift reaction and on the position of the charge transfer absorption band in a degenerate system has been studied by pulse radiolysis. The investigation focused in particular on the dependence of the effect on the size of the cation of the chemically inert electrolyte. Electrolytes caused dramatic rate reductions of 2-3 orders of magnitude. Unexpectedly, the rate reduction was found to increase with an increasing size of the cation. The recorded spectral blue shifts were as large as 0.5 eV and exhibited the expected tendency; the smaller counterions produced larger spectral shifts, due to a stronger Coulombic interaction. In both cases the effects exceeded the limits predicted by the continuum approach and pointed to the ion-pairing mechanism. The discrepancy between the dependence of the thermal electron transfer and the optically assisted electron transfer on the radius of the counterion could not be easily explained on purely energetic grounds, and the dynamics of the counterion had to be considered. Unfortunately, no agreement between the experimental results and the Eigen model of dissociative diffusion of ion pairsmore » in the zero ionic strength limit could be found. However, a qualitative correlation between the measured rates and the dissociation constants of the used salts, as well as the counterion mobilities was observed. 34 refs., 8 figs., 3 tabs.« less
Clinical and Epidemiological Correlates of Genotypes within the Mycobacterium avium Complex Defined by Restriction and Sequence Analysis of hsp65

Species identification of isolates of the Mycobacterium avium complex (MAC) remains a difficult task. Although M. avium and Mycobacterium intracellulare can be identified with expensive, commercially available probes, many MAC isolates remain unresolved, including those representing Mycobacterium lentiflavum as well as other potentially undefined species. PCR restriction analysis (PRA) of the hsp65 gene has been proposed as a rapid and inexpensive approach. We applied PRA to 278 MAC isolates, including 126 from blood of human immunodeficiency virus (HIV)-infected patients, 59 from sputum of HIV-negative patients with chronic obstructive pulmonary disease, 88 from environmental sources, and 5 pulmonary isolates from a different study. A total of 15 different PRA patterns were observed. For 27 representative isolates, a 441-bp fragment of the hsp65 gene was sequenced; based on 54 polymorphic sites, 18 different alleles were defined, including 12 alleles not previously reported. Species and phylogenetic relationships were more accurately defined by sequencing than by PRA or commercial probe. The distribution of PRA types and, by implication, phylogenetic lineages among blood isolates was significantly different from that for pulmonary and environmental isolates, suggesting that particular lineages have appreciably greater virulence and invasive potential.
Esophageal cancer screening by chromoendoscopy

There is renewed interest in chromoendoscopy, which is an old endoscopic technique first described more than two decades ago. It seems promising for improving detection of severe dysplasia and cancer of the esophagus. Staining with Lugol's solution is effective in detecting high-grade dysplasia and early squamous cancers of the esophagus, particularly in high-risk patients with head and neck cancers who may have synchronous esophageal tumors. It can also help delineate squamous from columnar metaplastic epithelium in patients with suspected Barrett's esophagus. Methylene blue selectively stains specialized columnar epithelium and may help diagnose short segment Barrett's esophagus. It may also direct biopsies to endoscopically inapparent high-grade dysplastic or malignant mucosa due to differential staining of dysplastic and nondysplastic tissue. In prospective studies involving patients and esophagectomy specimens, absent to light blue staining and heterogeneous staining pattern were significantly associated with high-grade dysplasia and/or adenocarcinoma. Biopsies from these areas led to detection of low grade dysplasia (five patients), high grade dysplasia (one patient), and adenocarcinoma (one patient) that were missed by random biopsy in a randomized sequential trial. When compared with 4-quadrant, jumbo random biopsy, methylene blue directed biopsy was significantly better in diagnosing intestinal metaplasia (Barrett's esophagus) and dysplasia, using fewer biopsies per patient. This led to a decrease in the overall and mean surveillance cost and the cost per cancer diagnosed. Chromoendoscopy is a simple, inexpensive, readily available endoscopic technique that may improve the diagnosis of esophageal cancer.
Design of the Discovery Channel Telescope mount

The Discovery Channel Telescope is a 4.2-meter clear aperture telescope undertaken by the Lowell Observatory in Flagstaff, Arizona. It will feature an interchangeable secondary assembly to allow the use of either a prime focus instrument or a secondary mirror. In addition, it will have an active optical system and provisions for a wide range of instruments. This paper describes the design of the telescope mount and drive systems. Particular challenges associated with the design include: consideration for the weight of the 3500 lb Prime Focus Assembly (PFA) instrument; interchangeable secondary assemblies; and providing thermal and mechanical stability in between updates to maintain alignment between optical elements.
Relationship of ethnicity, age, education, and reading level to speed and executive function among HIV+ and HIV– women: The Women's Interagency HIV Study (WIHS) Neurocognitive Substudy

Use of neuropsychological tests to identify HIV-associated neurocognitive dysfunction must involve normative standards that are well suited to the population of interest. Norms should be based on a population of HIV-uninfected individuals as closely matched to the HIV-infected group as possible and must include examination of the potential effects of demographic factors on test performance. This is the first study to determine the normal range of scores on measures of psychomotor speed and executive function among a large group of ethnically and educationally diverse HIV-uninfected, high-risk women, as well as their HIV-infected counterparts. Participants (n = 1,653) were administered the Trail Making Test Parts A and B (Trails A and Trails B), the Symbol Digit Modalities Test (SDMT), and the Wide Range Achievement Test–3 (WRAT–3). Among HIV-uninfected women, race/ethnicity accounted for almost 5% of the variance in cognitive test performance. The proportions ofvariance in cognitive test performance accou...
δ13C and δ18O Trends Across Overstory Environments in Whole Foliage and Cellulose of Three Pinus Species

Stable isotope ratios of carbon (δ13C) and oxygen (δ18O) are increasingly used to investigate environmental influences on plant physiology. Cellulose is often isolated for isotopic studies, but some authors have questioned the value of this process. We studied trends in δ13C and δ18O of whole foliage and holocellulose from seedlings of three Pinus species across three overstory environments to evaluate the benefits of holocellulose extraction in the context of a traditional ecological experiment. Both tissue types showed increasing δ13C from closed-canopy controls to thinned plots to 0.3 ha canopy gaps, and no change in δ18O between overstory environments. δ13C of P. resinosa and P. strobus was greater than δ13C of P. banksiana in whole foliage and holocellulose samples, and there were no differences in δ18O associated with species in either tissue type. Our results suggest whole foliage and holocellulose provide similar information about isotopic trends across broad environmental gradients and between species, but holocellulose may be better suited for studying differences in stable isotope composition between multiple species across several treatments.
Equipment and Method for Measurement of Power Factor of Mica

An investigation of domestic sources of mica has been under way for a number of years. The best single electrical property indicative of the suitability of the mica for use in radio condensers is its power factor. Equipment for measurement of power factor, commercially available previous to the present shortage of radio instruments, is described with test procedure.
Estimating equivalence with quantile regression

Equivalence testing and corresponding confidence interval estimates are used to provide more enlightened statistical statements about parameter estimates by relating them to intervals of effect sizes deemed to be of scientific or practical importance rather than just to an effect size of zero. Equivalence tests and confidence interval estimates are based on a null hypothesis that a parameter estimate is either outside (inequivalence hypothesis) or inside (equivalence hypothesis) an equivalence region, depending on the question of interest and assignment of risk. The former approach, often referred to as bioequivalence testing, is often used in regulatory settings because it reverses the burden of proof compared to a standard test of significance, following a precautionary principle for environmental protection. Unfortunately, many applications of equivalence testing focus on establishing average equivalence by estimating differences in means of distributions that do not have homogeneous variances. I discuss how to compare equivalence across quantiles of distributions using confidence intervals on quantile regression estimates that detect differences in heterogeneous distributions missed by focusing on means. I used one-tailed confidence intervals based on inequivalence hypotheses in a two-group treatment-control design for estimating bioequivalence of arsenic concentrations in soils at an old ammunition testing site and bioequivalence of vegetation biomass at a reclaimed mining site. Two-tailed confidence intervals based both on inequivalence and equivalence hypotheses were used to examine quantile equivalence for negligible trends over time for a continuous exponential model of amphibian abundance.
Are large differential stresses required for straight fracture propagation paths

Abstract Fracture growth geometries in linear elastic materials are sensitive to the ratio between the remote differential stress, or T -stress, and the fracture driving stress. Two mechanically interacting fractures follow straighter paths for greater values of this ratio. We demonstrate that the degree of curvature that develops between two mechanically interacting fractures is also controlled by such factors as sub-critical fracture growth and fracture surface roughness. Sub-critical fracture growth limits the development of fracture curvature by decreasing the fracture driving stress needed for propagation. Fracture surface roughness can affect the development of fracture curvature by limiting the magnitude of the shear displacement discontinuity that can be accommodated along the fracture. Thus, propagation paths for two mechanically interacting fractures can be quite straight even in the presence of small to moderate differential stresses. Consequently, the absence of fracture curvature does not necessarily imply a high differential stress state.
Sequence Comparison of JSRV with Endogenous Proviruses: Envelope Genotypes and a Novel ORF with Similarity to a G-Protein-Coupled Receptor

Abstract Ovine pulmonary carcinoma, a contagious lung cancer of sheep, is caused by the oncogenic jaagsiekte sheep retrovirus (JSRV) that is closely related to a family of endogenous sheep retroviral sequences (ESRVs). By using exogenous virus-specific U3 oligonucleotide primers, the entire JSRV proviral genome or its 3′ part was amplified from tumor DNA. Analysis of these proviral sequences revealed a novel open reading frame (ORF) within the pol coding region, designated ORF X, which was well conserved in ESRV and JSRV sequences. Deduced amino acids of ORF X showed similarity to a portion of the mammalian adenosine receptor subtype 3, a member of the G-protein-coupled receptor family. Comparison of deduced env amino acids of six JSRV strains from three continents identified 15 residues that defined two distinct genotypes of JSRVs. Sequence analysis identified two highly variable regions between JSRV and ESRV in the transmembrane domain of env (TM) and the 3′ unique sequence (U3) of the long terminal repeat, from which JSRV-specific DNA probes were derived. By using these DNA probes in Southern hybridization, for the first time we successfully identified JSRV proviral sequences in tumor genomic DNA in the presence of multiple ESRV loci, validating the use of exogenous virus-specific DNA probes in the analysis of oncogenic proviral integration sites and identification of integrated exogenous proviral sequences.
Numerical experiments of partial phase conjugation due to a random phase screen

A simulation was constructed and numerical experiments conducted of optical wave double pass propagation through a phase screen. The phase screen had a Gaussian phase fluctuation with a Kolmogorov power law spatial spectrum. The results showed a statistically partial phase conjugation.
Regional distribution of magnetic secular‐variation over the Earth's surface

The term “secular variation” is generally used to signify the slow change in the Earth's magnetic field which requires centuries for its full development. In but few places are there records from which a reliable knowledge of these changes may be gained for any considerable period of the past, and such records are confined very generally to one element only, the declination. But aside from changes in the Earth's field considered as a whole there are regional peculiarities which undergo changes of a much more rapid nature, permitting a more complete investigation from records of comparatively few years, and promising to yield vital information not only to the subject of terrestrial magnetism but to other allied branches of geophysics, dealing with forces at work in the interior of the Earth.
Detection of tabtoxin‐producing strains of Pseudomonas syringae by PCR

J. LYDON AND C. D. PATTERSON. 2001. Aims: The present study describes a system based on PCR to distinguish tabtoxin-producing strains of Pseudomonas syringae from other Ps. syringae plant pathogens that produce chlorosis-inducing phytotoxins. Methods and Results: Thirty-two strains of Ps. syringae and related species were examined. Two sets of PCR primers were developed to amplify genes (tblA and tabA) required for tabtoxin production. Only a PCR product of 829 bp or 1020 bp was produced in PCR reactions with the tblA or tabA primer sets, respectively, and cells from tabtoxin-producing pathovars of Pseudomonas syringae. All known non-tabtoxin producing bacterial species failed to produce an amplification product with either primer set. Conclusions: PCR of genes required for tabtoxin production is a simple, rapid and reliable method for identifying tabtoxin-producing strains of Ps. syringae. Significance and Impact of the Study: The protocol can effectively distinguish tabtoxin-producing strains of Ps. syringae from other Ps. syringae pathovars and Ps. syringae pv. tabaci strains from other tabtoxin-producing Ps. syringae pathovars.
Cystometry and periurethral striated muscle electromyography using cold and room temperature fluid.

Abstract In evaluating patients with neurologic lesions of the spinal cord and voiding abnormalities, it would appear from this study that distention is a more physiologic stimulus to bladder contraction than relatively smaller amounts of cold fluid. While the ice water test has speed and simplicity to recommend it, it should not be used as a sole means in determining whether or not a detrusor reflex is present. It may not uncover those patients with detrusor hyperreflexia or may fail to reveal a detrusor reflex. If iced contrast medium is to be used for voiding cystography, the volumes should approximate those used for regular cystometry.
A control problem for clamped extensible beams

An optimal control problem for a nonlinear partial integro-differential equation is presented. Existence of an optimal control is obtained, and a minimum principle is proved
A New Pressure Boundary Condition of Lattice Boltzmann Method (LBM) for Fully Developed Pressure-Driven Periodic Incompressible Fluid Flow

In this paper, a new pressure boundary treatment of lattice Boltzmann method (LBM) for fully developed pressure-driven periodic incompressible fluid flow is proposed. The pressure gradient, instead of equivalent body force, has been applied to determine the particle distribution function on the periodic traverse sections for the fully developed pressure-driven periodic flow. Numerical simulations, including 2D pressure-driven Poiseuille flow and fluid flow passing square obstacles, are carried out using this new boundary treatment. Simulation results show that the proposed approach not only overcomes the nonphysical inlet and outlet flow disturbances (which the LBM simulation always suffers from using the existing pressure boundary methods), but also preserves the system periodicity and generates consistent pressure distribution with macroscopic periodic boundary conditions for the pressure-driven incompressible fluid flow.Copyright © 2008 by ASME
Persistent fetal occiput posterior position: obstetric outcomes.

Abstract Objective To evaluate the obstetric outcomes associated with persistent occiput posterior position of the fetal head in term laboring patients. Methods We performed a cohort study of 6434 consecutive, term, vertex, laboring nulliparous and multiparous patients, comparing those who delivered infants in the occiput posterior position with those who delivered in the occiput anterior position. We examined maternal demographics, labor and delivery characteristics, and maternal and neonatal outcomes. Results The prevalence of persistent occiput posterior position at delivery was 5.5% overall, 7.2% in nulliparas, and 4.0% in multiparas (P Conclusion Persistent occiput posterior position is associated with a higher rate of complications during labor and delivery. In our population, the chances that a laboring woman with persistent occiput posterior position will have a spontaneous vaginal delivery are only 26% for nulliparas and 57% for multiparas.
Secure communications over insecure channels

According to traditional conceptions of cryptographic security, it is necessary to transmit a key, by secret means, before encrypted massages can be sent securely. This paper shows that it is possible to select a key over open communications channels in such a fashion that communications security can be maintained. A method is described which forces any enemy to expend an amount of work which increases as the square of the work required of the two communicants to select the key. The method provides a logically new kind of protection against the passive eavesdropper. It suggests that further research on this topic will be highly rewarding, both in a theoretical and a practical sense.
Some floristic characteristics of the northern Chihuahuan Desert: a search for its northern boundary

An index of Chihuahuan floristic affinity was constructed to characterize the floristic variation over a 5° latitudinal gradient in the northern Chihuahuan Desert, with an emphasis on evaluating northern boundary conditions. The index was based on evaluating the ranges of 494 species from 590 vegetation plots from Bouteloua eriopoda and B. gracilis grasslands and Larrea tridentata scrub, distributed among four sites along the gradient. The most northern site, the Sevilleta National Wildlife Refuge (34°N latitude), while maintaining a complement of primarily southern distributed species, had the lowest index values and the fewest Chihuahuan endemics (3%) and Southwestern desert species (19%) in general. At the intermediate sites (Jornada/Tularosa basins and Otero Mesa), one and two degrees further south, index values increased conspicuously along with number of Chihuahuan endemics (7%) and the Southwestern desert species (37%). At 29°N latitude, the Sierra del Carmen Protected Area in northern Mexico was the furthest southern site. It represented typical hot and dry Chihuahuan Desert conditions where Chihuahuan endemics comprised 29% of species complement and Southwestern desert species made up 55%. With respect to floristic boundaries, the Sevilleta was clearly transitional to the southern Shortgrass Prairie and Intermountain (Great Basin-Colorado Plateau) provinces. While it supported several grassland and shrubland associations that maintained their overall Chihuahuan character, there were also several associations with primarily northern affinities, and also a set unique to the Sevilleta, reflecting its ecotonal nature. The results show that sound biosystematics, biogeographical analyses and indices like those presented here can provide an important context for questions in synecology, plant ecology, and conservation biology.
Temperature-independent diel variation in soil respiration observed from a temperate deciduous forest

The response of soil respiration (Rs) to temperature depends largely on the temporal and spatial scales of interest and how other environmental factors interact with this response. They are often represented by empirical exponential equations in many ecosystem analyses because of the difficulties in separating covarying environmental responses and in observing below ground processes. The objective of this study was to quantify a soil temperature-independent component in Rs by examining the diel variation of an Rs time series measured in a temperate deciduous forest located at Oak Ridge, TN, USA between March and December 2003. By fitting 2 hourly, continuous automatic chamber measurements of CO2 efflux at the soil surface to a Q10 function to obtain the temperature-dependent respiration (Rt) and plotting the diel cycles of Rt, Rs, and their difference (Ri), we found that an obvious temperature-independent component exists in Rs during the growing season. The diel cycle of this component has a distinct day/night pattern and agrees well with diel variations in photosynthetically active radiation (PAR) and air temperature. Elevated canopy CO2 concentration resulted in similar patterns in the diel cycle of the temperature-independent component but with different daily average rates in different stages of growing season. We speculate that photosynthesis of the stand is one of the main contributors to this temperature-independent respiration component although more experiments are needed to draw a firm conclusion. We also found that despite its relatively small magnitude compared with the temperature-dependent component, the diel variation in the temperature-independent component can lead to significantly different estimates of the temperature sensitivity of soil respiration in the study forest. As a result, the common practice of using fitted temperature-dependent function from night-time measurements to extrapolate soil respiration during the daytime may underestimate daytime soil respiration.
The inhibition of 3H-biogenic amine uptake by 5,6-dihydroxytryptamine: A comparison with the effects of 6-hydroxydopamine

5,6-Dihydroxytryptamine was a competitive inhibitor of both 3H-serotonin and 3H-dopamine uptake into rat brain tissue slices. In contrast, 6-hydroxydopamine inhibited 3H-dopamine uptake but did not inhibit 3H-serotonin uptake even at a 6-Hydroxydopamine concentration of 10−4 M. In these experiments, catalase was present in the incubation medium to decompose hydrogen peroxide which is a product of the autoxidation of 6-hydroxydopamine and an inhibitor of biogenic amine uptake systems. These above data may help to explain the relative specificity of 6-hydroxydopamine for adrenergic nerve terminals in contrast to the effects of 5,6-dihydroxytryptamine on both adrenergic and serotonergic nerve terminals. Kinetic analyses showed that 5,6-dihydroxytryptamine had almost the same affinity for the 3H-serotonin transport system as did 3H-serotonin itself. In contrast, 5,6-dihydroxytryptamine had an affinity for the 3H-dopamine transport system approximately 1/30 that of 3H-dopamine.
Communications: Comparison of Fall and Spring Tumors as Inocula for Experimental Transmission of Walleye Dermal Sarcoma

Abstract To determine if the walleye dermal sarcoma virus (WDSV) was present in both spring regressing tumors and fall developing tumors, an experimental transmission trial was conducted with cell-free tumor filtrates. A relatively high portion (82%) of young-of-the-year (age-0) walleyes Stizostedion vitreum inoculated with filtrates of spring-collected tumors developed dermal sarcomas. Conversely, no dermal sarcomas were observed on age-0 walleyes inoculated with filtrates of a tumor collected in the fall. Northern blot analysis demonstrated high levels of WDSV RNA in spring tumors and in inoculum derived from spring tumors, but very little viral RNA was detectable from fall tumors or inoculum derived from fall tumors.
Estimating sodium pump activity in beating heart muscle

Abstract There are substantial problems associated with the biochemical estimation of sodium pump activity. These have been often neglected, resulting in an inaccurate interpretation of results. The on-going sodium pump activity and the capacity of the sodium pump has to be considered separately. In beating heart muscle, the best direct approximation of these parameters results from estimation of ouabain-sensitive 86 Rb + uptake observed during a short incubation period under conditions in which rate of Na + influx is suddenly increased. A more accurate, though indirect, estimation of sodium pump inhibition may be obtained from measuring the reduction in initial velocity of the [ 3 H]ouabain binding reaction using tissue homogenates obtained from drug-exposed preparations.
An energy and deadline aware resource provisioning, scheduling and optimization framework for cloud systems

Cloud computing has attracted significant attention due to the increasing demand for low-cost, high performance, and energy-efficient computing. Profit maximization for the cloud service provider (CSP) is a key objective in the large-scale, heterogeneous, and multi-user environment of a cloud system. This paper addresses the problem of minimizing the operation cost of a cloud system by maximizing its energy efficiency while ensuring that user deadlines as defined in Service Level Agreements are met. The workload in the cloud system can be modeled as independent batch requests or as task graphs with dependencies. This paper adopts the latter modeling approach, which provides more opportunities for energy and performance optimizations, thus enabling the CSP to meet user deadlines at lower operation costs. However, these optimizations require additional supporting efforts e.g., resource provisioning, virtual machine placement, and task scheduling, which are addressed in a holistic manner in the proposed framework. In the envisioned cloud environment, users can construct their own services and applications based on the available set of virtual machines, but are relieved from the burden of resource provisioning and task scheduling. The CSP will then exploit data parallelism in user workloads to create an energy and deadline-aware cloud platform.
The dangers of death‐wish marketing

Marketing practices are generally unhealthy. Reports of marketing success are wildly and widely exaggerated. Indeed, marketing efforts and practices rarely succeed if one defines success as demonstrating a reasonable return on investment. For example, 16,000 new package goods were introduced into American supermarkets and pharmacies last year, and 80 percent failed. Research suggests similar failure rates for new movies; financial products and services; and consumer durables, including automobiles, appliances and consumer electronics. One CEO of a major company admitted last year: “We would have made more money if we had taken everything we spent creating and introducing new products in the last ten years and put it into certificates of deposit.”
Perceived Causal Influences of Weather Rating the Weather's Influence on Affective States and Behaviors

Perception of weather's causal influence was examined. Using a revised model of the attributional process, predicted that the weather's perceived influence would be greater for observers than for actors, for affective states than for behaviors, for negative affective states and behavior than for positive ones, and for individuals with an external rather than internal locus of control. Subjects were asked to rate weather's influence on 50 affective states and 108 behaviors. Based on previous ratings of their social desirability value, half of the items in each category were positively valued and half negatively. Some subjects were asked to rate the weather's influence on themselves and some on other people. Subjects also completed Rotter's Locus of Control scale using a Likert response format. Analysis of variance on the weather influence ratings supported the first, second, and last hypotheses but not the third. Positive feelings and behavior were rated as being more heavily influenced than negative ones.
Production of zoospores, mode of infection, and inoculum potential of Pythium myriotylum propagules on cocoyam.

Zoospores of Pythium myriotylum were consistently produced from sporangia of detached mycelia in vitro in deionized water at pH 7.0 with 0.001 M sucrose in 24 h of continuous fluorescent light at 31°C. The oblong-to-pea shaped zoospores measured from 2.5–7.5 μm in diameter and remained motile for more than 48 h. The lengths of flagella were 1–1.5 times the diameter of the zoospores. Contaminated cultures of P. myriotylum were revived to pure isolates by the use of zoospores. The penetration of P. myriotylum propagules took from 6 to 7 h following contact of the inoculum with the roots, and the invasion was inter- and intracellular. At the minimum concentrations of 200 zoospores/ml or 180 mycelial strands/ml, P. myriotylum caused symptoms of CRRD within 3 to 6 days after inoculation of the roots of cocoyam plantlets, results indicating that the pathogen is very destructive in cocoyam.
Human immunodeficiency virus-associated Hodgkin's disease. Clinicopathologic studies of 24 cases and preponderance of mixed cellularity type characterized by the occurrence of fibrohistiocytoid stromal cells.

Hodgkin's disease (HD) was diagnosed in 24 patients who were either seropositive for human immunodeficiency virus (HIV) (21) or members of a high-risk group (three), but had not developed acquired immune deficiency syndrome (AIDS). Clinical presentation of the disease was characterized by constitutional symptoms in all, especially fever (23/24) and disseminated disease (22/24) at diagnosis. Mediastinal adenopathy was rare. Bone marrow involvement was particularly frequent (12/24), and a positive bone marrow biopsy preceded lymph node biopsy in 5 of the 12. Histopathologic features of these tumors included an increased number of nonlymphoid stromal cells, i.e., histiocytic and/or fibroblastoid. In some tumors these fibrohistiocytoid stromal cells were arranged in bundles, but distinct nodule with birefringent collagen band formation was not observed. Twenty-two patients were treated, most with combination chemotherapy; one was untreated; one, unknown. Sixteen, including the one untreated, died with disease at 3 to 25 months; one died of an unrelated cause; four were alive at 3 to 24 months; three were lost to follow-up. Frequent bone marrow involvement at presentation suggests the usefulness of the bone marrow biopsy for diagnosis in subjects at risk, especially when they present with spiking fever of unknown origin. Contrary to most previous series, virtually all of our cases were of mixed cellularity type, characterized by increased fibrohistiocytoid stromal cells in place of depleting lymphocytes. The classic nodular sclerosing feature with birefringent collagen band formation was not observed. In conclusion, HIV-associated HD was characterized by advanced stage with fever at presentation, preponderance of mixed cellularity histologic type with increased fibrohistiocytoid stromal cells, and poor outcome. Hodgkin's disease in AIDS patients presents an intriguing biological model to study the role of stromal histiocytes in immunodeficient patients.
Resonance behavior of buried landmines

A 3D finite-difference time-domain model for elastic waves in the ground has been developed and implemented on a massively parallel computer. The numerical model has been developed as part of a project in which elastic and electromagnetic waves are used synergistically to detect buried land mines. The numerical model is used to study the interaction of elastic waves with buried land mines. As a first approach, a simple model for a TS-50 antipersonnel mine has been developed, and the interaction of elastic waves with the buried mine has been investigated. In both experimental results and numerical simulations, resonant oscillation occur at the location of buried mine. To further explore the resonant behavior of a buried land mine, a refined mine model has been developed that includes more details of the actual mine. Using the refined mine model, the nature of the resonance is explained, and the parts of the mien that influence the resonant oscillations are identified. Results are presented which describe the resonance as a function of burial depth and soil parameters.
Rhetoric and science journalism

(1970). Rhetoric and science journalism. Quarterly Journal of Speech: Vol. 56, No. 4, pp. 358-368.
Detecting conjuctions of global predicates

We present an efficient algorithm to detect if the conjunction of two nonlocal predicates is possibly true in a distributed computation. For offline detection of such global predicates, our algorithm is significantly more efficient than the previous algorithms by Cooper and Marzullo, and by Stoller and Schneider.
Women, Weight, and Age: Social Comparison to Magazine Images Across the Lifespan

The finding that rates of body dissatisfaction in women remain relatively stable across the adult lifespan may be due to older women having fewer but heavier age-relevant comparisons in the media. To examine this, magazine images that depict women’s full bodies were coded for age, body size, and clothedness. Analyses suggest that overall, older women are not well represented in this medium. In addition, magazines aimed at younger women depict younger and thinner models than do those magazines with a larger percentage of older readers. Moreover, across magazines, younger models are thinner and less clothed than older models. Thus, larger body ideals portrayed in the media, in combination with increased weight with age, may contribute to similarities in body satisfaction over the lifespan.
Dronedarone: Emergence of a New Therapeutic Option for the Treatment of Atrial Fibrillation:

This continuing feature updates readers on recent developments in cardiovascular pharmacotherapy. Cardiovascular disease remains the number 1 killer in the United States, and more clinical outcome trials have been conducted in cardiology than in any other field of medicine. Given this rapidly expanding knowledge base, if pharmacists stay current with developments in drug therapy, they can have a significant impact on prevention and treatment.
A higher-order finite element for analysis of composite laminated structures

Abstract A new six-node higher-order triangular composite layered shell finite element with six degrees of freedom at each node is presented. With respect to the inplane variables, the in-plane and the out-of-plane displacement fields of the element are quadratic and cubic respectively. By using Utku's method (AFFDL-TR-71-160, Air Force Third Conf., Wright Paterson, Ohio, 1971), the transverse shear strain energy is computed directly from the displacement field rather than from the stress couple field. Some typical bending problems for composite laminated beams and plates with different stack sequences are analyzed. Excellent agreements are obtained when compared to the exact solutions, the first order shear deformation theory (FSDT), the higher order shear deformation theory (HSDT) and some other existing finite element models. ‘Shear locking’ is avoided when the plate is thin.
The Impact of Settable Test Item Exposure Control Interface Format On Postsecondary Business Student Test Performance

A search of theERICdatabase reveals a keen interest in computer-based testing by researchers over the past 35 years. Indeed, a focused search of theERICdatabase using the descriptor "computer assisted testing" from 1970 through 2003 returned 1,954 citations. More than half (55.6%,n= 1,105) of these 1,954 citations were dated from 1990 through 2003. This research interest in computer-based testing is likely a result of the many advantages associated with its use (Goldberg & Pedulla, 2002). A number of researchers have reported on the advantages of computer-based testing (e.g.,Alderson, 2000;Alexander, Bartlett, Truell, & Ouwenga, 2001;Barkley, 2002;Bocij & Greasley, 1999;DeSouza & Fleming, 2003;Goldberg & Pedulla, 2002;Greenberg, 1998;Shermis & Lombard, 1998;Shermis, Mzumara, & Bublitz, 2001;Song, 1998;Stephens, 2001;Truell & Davis, 2003). Often cited advantages of computer-based testing include decreased testing costs, effective records management, increased assessment options, improved scoring precision, instant feedback to students, more instructional time, more test administration choices, and reduced testing time. Despite the many advantages associated with computer-based tests for student assessment purposes, there are several areas of concern associated with their use. Two areas of concern with computer-based test use are user interfaces and test item exposure control formats.
Applications of service curve theory

In this paper, we study well-known utilization-based admission control schemes which are derived by ad-hoc mathematical manipulations in previous literatures. We show that the same results can easily be achieved by using service curve theory (SCT). We also investigate the problem of providing statistical quality of service (QoS) in wireless network. With the same idea as the service curve theory, we can find an approximation formula to estimate drop probabilities in the Cruz (1995) and Agarwal et. al. (1999) delay system. In general, this analysis methodology is effective and can be used in the delay analysis of other applications.
Bolus administration of cladribine in the treatment of Waldenström macroglobulinaemia

This phase II clinical trial evaluated bolus cladribine as a single agent in Waldenstrom macroglobulinaemia (WM). Cladribine was administered to 20 patients at a dose of 0.12 mg/kg/d by 2 h intravenous infusion for 5 consecutive days at monthly intervals for three courses. Partially responding patients were continued on therapy until maximal response and/or prohibitive toxicity, to a maximum of eight courses. Complete responders were treated with one additional course of cladribine. After a median of three courses of cladribine, all 20 patients were evaluable; one achieved a complete response (CR) (5%) and 10 achieved a partial response (PR) (50%). The median duration of response follow-up was 28 months (range 1–37 months). Four of 7 (57%) untreated and 7/13 (54%) previously treated patients responded. The major toxicity encountered was myelosuppression with 60% of patients demonstrating grade 3 or 4 neutropenia. Non-haematological toxicities included two patients with herpes zoster and two patients with non-melanoma skin cancers. At a median follow-up duration of 20 months, 17 patients remain alive and three have died. We confirm that bolus cladribine is an effective and safe method of drug delivery in WM patients. Recommendations regarding the equivalence of the continuous infusion and bolus methods in untreated patients requires further study. Bolus cladribine is more convenient and less costly than infusional cladribine since it obviates the need for central catheters and infusional devices.
Molecular Biology of Pancreatic Cancer: How Useful Is It in Clinical Practice?

Context During the recent two decades dramatic advances of molecular biology allowed an in-depth understanding of pancreatic carcinogenesis. It is currently accepted that pancreatic cancer has a genetic component. The real challenge is now how these impressive advances could be used in clinical practice. Objective To critically present currently available data regarding clinical application of molecular biology in pancreatic cancer. Methods Reports about clinical implications of molecular biology in patients with pancreatic cancer were retrieved from PubMed. These reports were selected on the basis of their clinical relevance, and the data of their publication (preferentially within the last 5 years). Emphasis was placed on reports investigating diagnostic, prognostic, and therapeutic implications. Results Molecular biology can be used to identify individuals at high-risk for pancreatic cancer development. Intensive surveillance is indicated in these patients to detect pancreatic neoplasia ideally at a preinvasive stage, when curative resection is still possible. Molecular biology can also be used in the diagnosis of pancreatic cancer, with molecular analysis on samples of biologic material, such as serum or plasma, duodenal fluid or preferentially pure pancreatic juice, pancreatic cells or tissue, and stools. Molecular indices have also prognostic significance. Finally, molecular biology may have therapeutic implications by using various therapeutic approaches, such as antiangiogenic factors, purine synthesis inhibitors, matrix metalloproteinase inhibitors, factors modulating tumor-stroma interaction, inactivation of the hedgehog pathway, gene therapy, oncolytic viral therapy, immunotherapy (both passive as well as active) etc. Conclusion Molecular biology may have important clinical implications in patients with pancreatic cancer and represents one of the most active areas on cancer research. Hopefully clinical applications of molecular biology in pancreatic cancer will expand in the future, improving the effectiveness of treatment and prognosis of patients with pancreatic cancer.
Inhibition of peptide deformylase in Nicotiana tabacum leads to decreased D1 protein accumulation, ultimately resulting in a reduction of photosystem II complexes

Eukaryotic homologs of bacterial peptide deformylases were recently found in several vascular plants and may be essential in chloroplast protein processing. Treating tobacco seedlings with the peptide deformylase inhibitor actinonin resulted in leaf chlorosis and reduced growth and development, indicative of a systemic movement of the inhibitor. Photosystem II (PSII) activity was reduced, manifested as a significant decrease in the maximum quantum efficiency of photosystem II. Accumulation and assembly of nascent D1 protein into PSII monomers was also reduced, eventually leading to PSII disassembly and leaf necrosis. Processing and assembly of D1 protein in tobacco was a major and potentially critical target of peptide deformylase inhibition. These results confirm that Nterminal deformylation is an essential step in the accumulation and assembly of PSII subunit polypeptides in the chloroplasts of vascular plants.
Simmons' protocol is not free of subliminal channels

At the VIth Computer Security Foundations Workshop Simmons presented a protocol to make the Digital Signature Standard free of any subliminal channels. As Simmons has pointed out at several occasions the design of protocols is very difficult and one has claimed protocols to have certain properties, they turned out not to have. In this paper we demonstrate that Simmons' protocol is not free of any subliminal channels, by presenting a subliminal channel with a small capacity. We also discuss generalizations which imply that several already presented protocols claimed to be "subliminal-free" are not.
Interacting Components of the Flagellar Motor ofEscherichia coliRevealed by the Two-hybrid System in Yeast

The ability of the flagellar motor ofEscherichia colito switch between clockwise and counterclockwise modes of operation is ultimately responsible for the swimming behavior of the cell. Three motor proteins, FliG, FliM, and FliN, have been implicated in this process. Using the two-hybrid system inSaccharomyces cerevisiae, we demonstrated strong interactions between FliG/FliM, FliM/FliM, and FliM/FliN. A screen for other components that might interact with FliG revealed interactions with FliF (the MS ring protein) and H-NS (a histone-like protein). Regions of proteins important for several of these interactions were identified by mutational analysis. The implications for motor assembly and function are discussed.
Minimally invasive closure of pediatric umbilical hernias

Abstract Background Pediatric umbilical hernias may close spontaneously by concentric fibrosis and scar tissue formation. Some hernias do not close. This study was developed to assess this novel minimally invasive closure (MIC), using injectable material to close the umbilical defect. Method Twenty-five children with umbilical hernias of 1.5 cm or less were included in the study. Deflux (Q Med, Uppsala, Sweden), a biodegradable compound of dextranomer microspheres in hyaluronic acid, was injected percutaneously in the border and preperitoneal space in 4 quadrants of the hernia defect, thereby occluding the lumen. Follow-up visits were obtained at approximately 1 week, 3 months, and 1 year. Results Two to twenty-four months after surgery, 21 of the 25 umbilical hernias were closed (84%). To date, there have been no complications from the injected compound substance. The average age at the time of the MIC was 6 years and 7 months, ranging from 4 months to 17 years. The average defect was more than 6.4 mm, ranging from 4 to 14 mm. Conclusion Minimally invasive closure procedure with injection of dextranomer hyaluronic acid copolymer can safely be used to close umbilical hernias. The procedure closed or reduced the size of hernias in our patients immediately after surgery; and within months, 21 (84%) of 25 were closed. One defect has not closed in 1 year and will need repair. The remaining 3 defects are small and may go on to close by ongoing fibroblast ingrowth and collagen deposit. The MIC procedure may be an alternative to open repair of umbilical hernias. Increased experience and long-term follow-up will determine the true efficacy of this new technique.
A numerical analysis of crack propagation in microcracking ceramic and ceramic composites

Abstract In this study, a set of numerical analyses of crack growth performed to elucidate the mechanism of microcracking on the observed fracture behaviour of brittle solids and composites is described. The random nucleation, orientation and size effects of discrete microcracks and resulting interactions are fully accounted for in a hybrid finite-element model. The results indicate that the energy expenditure due to microcrack nucleation seems not to contribute significantly to the resistance to crack growth. The main controlling parameter appears to be elastic interaction of the microcracks with the main crack in the absence of a reinforcing phase; therefore, the microcrack density plays an important role. In the case of composites, the interaction of the main crack with the stress fields of the reinforcing phase, rather than interaction of microcracks, is the controlling parameter for the resistance to crack growth even in the presence of a large population of microcracks. It is also shown that crack branching and crack kinking can readily develop as a result of microcracking.