cssi/SciSciGPT-SciSciNet huggingface dataset:
Explicit sums and integrals over complete sets of intermediate states of hydrogen

The bound-state and continuum solutions of the Schr\"odinger equation in a Coulomb potential are presented once again, but in a form that makes similarities in their structure much more apparent than before. The similarity is particularly striking if Laplace transforms are used. Not only are both bound state and continuum solutions of the same form, but they also have a simple structure for arbitrary energy eigenvalues. The usefulness of the formalism is illustrated by considering a number of examples involving infinite sums over bound states and integrals over continuum states of matrix elements that were relevant in past work.
Trends and geographic variation of potentially avoidable hospitalizations in the veterans health-care system.

The rate of hospitalizations due to ambulatory care-sensitive conditions (ACSCs) has been widely accepted as an indicator of access and quality of primary care. This study aimed to examine the trends and geographic variation of ACSC hospitalizations in US veterans health-care system, to identify factors associated with ACSC hospitalizations and to develop a quality indicator that can monitor access and effectiveness of primary care at hospital level. Using fiscal years 1997–2007 data, we found total ACSC hospitalizations per 1000 ACSC patients decreased by 58%; ACSC hospitalizations as percentage of total hospitalizations decreased 9%. However, significant geographic variations of ACSC hospitalizations remained and we found that adjustment of case-mix or confounding factors was essential in making meaningful comparisons among hospitals in a health-care system. Further, this study also reveals that low-income veterans still had higher ACSC hospitalization rates and patient travel time less than 30 minutes ...
Lambert-Eaton myasthenic syndrome: The lack of short-term in vitro effects of serum factors on neuromuscular transmission

Serum was obtained from 7 patients with the Lambert-Eaton myasthenic syndrome (LES), 3 patients with small-cell carcinoma of the lung (SCCL), and 9 healthy control subjects. Serum samples were applied in vitro to the rat neuromuscular junction (for 1-3 h for control LES sera; 4 h for SCCL sera), following which the pre- and postjunctional physiological effects of serum factors were studied in the presence of 10 mM [Mg2+]o. All sera produced a marked reduction in the frequency of spontaneous miniature end-plate potentials (MEPPs), while causing slight to moderate changes in MEPP amplitude. There were no consistent changes in the quantum content of the impulse-evoked end-plate potentials, though the serum from one LES patient significantly and reversibly inhibited the evoked quantal release. No significant effect was found when a human intercostal muscle was exposed to serum from another LES patient for 2 h. Therefore, when applied in vitro on a short-term basis, the putative LES autoantibodies do not consistently react with voltage-dependent calcium channels in the motor nerve terminal and thus fail to reproduce the physiologic abnormality of the syndrome. We suggest that the pathogenic IgG molecules may require more than 3h of incubation in order to gain access to, and inhibit the function of, the prejunctional Ca2+ channels.
Interaction of External K, Na, and Cardioactive Steroids with the Na-K Pump of the Human Red Blood Cell

The interaction of extracellular Na (Nao), K (Ko), and strophanthidin with the Na-K pump of the human red blood cell has been investigated. Inhibition by submaximal concentrations of strophanthidin rapidly reaches a level which does not increase further over a relatively long period of time. Under these circumstances, it is possible to apply a steady-state kinetic analysis to the interaction of Nao, Ko, and strophanthidin with the pump. In Na-free solutions, strophanthidin increases the apparent K1/2 of the pump for Ko, but does not change the form of the relation between the reciprocal of the active K influx (iMKP–1) and the reciprocal of [Ko] ([Ko]–1); the relation both in the presence and absence of strophanthidin is adequately described by a straight line. In solutions containing Na, strophanthidin changes the form of the curve describing the relation between iMKP–1 vs. [Ko]–1; the curve becomes more parabolic in solutions containing strophanthidin. The rate of ouabain binding to K-free cells has also been measured; in the absence of K, the rate of binding is unaffected by Nao. The data are considered in terms of a simple kinetic model. The findings can be explained if it is supposed that at low external K the form of the pump combined with one Nao is more likely to combine with strophanthidin than is the uncombined form of the pump. The uncombined form of the pump is more likely to combine with K even at very low Ko than with strophanthidin.
Triadic Reality, the Now System, and Maternal Desire: Thoughts on Daphne de Marneffe's Maternal Desire

Maternal desire is discussed as it coexists with and is tutored by paternal desire and the spousal relationship. Triadic reality and the Now moment are introduced as relevant variables in the regulation of all intrapsychic and interactive phenomena.
A qualitative comparison of paper flowsheets vs a computer-based clinical information system.

Demonstrating the value of computerized clinical information systems (CIS) relative to its cost has been difficult. Decreased mortality in the intensive care unit or a reduction in nursing staff have not been apparent, but CIS does lead to a significant improvement in documentation over handwritten flowsheets, both in volume and accuracy. This may have a medicolegal and quality assurance impact, as well as enhancing patient care. (Chest 1991; 99:155–57)
Mechanoregulation of human articular chondrocyte aggrecan and type II collagen expression by intermittent hydrostatic pressure in vitro

This study addressed the hypothesis that duration and magnitude of applied intermittent hydrostatic pressure (IHP) are critical parameters in regulation of normal human articular chondrocyte aggrecan and type II collagen expression. Articular chondrocytes were isolated from knee cartilage and maintained as primary, high-density monolayer cultures. IHP was applied at magnitudes of 1, 5 and 10 MPa at 1 Hz for durations of either 4 h per day for one day (4 x 1) or 4 h per day for four days (4 x 4). Total cellular RNA was isolated and analyzed for aggrecan and type II collagen mRNA signal levels using specific primers and reverse transcription polymerase chain reaction (RT-PCR) nested with beta-actin primers as internal controls. With a 4x1 loading regimen, aggrecan mRNA signal levels increased 1.3- and 1.5-fold at 5 and 10 MPa, respectively, relative to beta-actin mRNA when compared to unloaded cultures. Changing the duration of loading to a 4x4 regimen increased aggrecan mRNA signal levels by 1.4-, 1.8- and 1.9-fold at loads of 1, 5 and 10 MPa, respectively. In contrast to the effects of IHP on aggrecan, type II collagen mRNA signal levels were only upregulated at loads of 5 and 10 MPa with the 4x4 loading regimen. Analysis of cell-associated protein by western blotting confirmed that IHP increased aggrecan and type II collagen in chondrocyte extracts. These data demonstrate that duration and magnitude of applied IHP differentially alter chondrocyte matrix protein expression. The results show that IHP provides an important stimulus for increasing cartilage matrix anabolism and may contribute to repair and regeneration of damaged or diseased cartilage.
Energy Gap Dependence of the Efficiency of Charge Separation upon the Sacrificial Reductive Quenching of the Excited States of Ru(II)-Diimine Photosensitizers in Aqueous Solution

The yield of oxidized and reduced products released into the bulk solution upon electron−transfer quenching is the critical parameter governing the efficacy of a redox photosensitizer. The cage esc...
Anterior Insular Cortex Anticipates Impending Stimulus Significance

Touch is a fundamental, but complex, element of everyday interaction that impacts one's sensory and affective experience via interoceptive processing. The insular cortex is an integral component of the neural processes involved in interoception, i.e. the generation of an "emotional moment in time" through the sensing of the internal body state (Craig, A.D., 2002. How do you feel? Interoception: the sense of the physiological condition of the body. Nat. Rev. Neurosci 3, 655-666.). Here, we examine the contribution of different parts of the insular cortex in the representation of both affective and sensory aspects of touch. To that end, subjects were administered a cued application of touch during functional MRI. We find that stimulus-related activation occurs in the mid-to-posterior insula, whereas anticipatory related activation is seen mostly in anterior insula. Moreover, the degree of activation in anterior insula during anticipation is correlated with the degree of activation in the posterior insula and caudate during stimulus processing. Finally, the degree of activation in the anterior insula during anticipation is also correlated with experienced intensity of the touch. Taken together, these results are consistent with the hypothesis that the anterior insula is preparing for the sensory and affective impact of touch. This preparatory function has important implications for the understanding of both anxiety and addictive disorders because dysfunctions in anticipatory processing are a fundamental part of the psychopathology.
A mechanistic study of transgranular stress corrosion cracking of type 304 stainless steel

Transmission electron microscopy (TEM) was utilized to characterize the deformation substructure of 304 stainless steel tested for transgranular stress corrosion cracking (TGSCC) in 45 wt pet MgCl2 at 155 °C. The TEM characterization was conducted in thin foils prepared from the fracture surface and from a series of known depths below the fracture surface. The results indicate that the stacking fault energy (SFE) of the material immediately ahead of the crack tip is lowered, with the deformation mode at small distances (a few microns) in front of the growing crack front being entirely coplanar while at larger distances homogeneous. The reduction in the SFE is attributed to absorbed hydrogen formed during the cathodic reaction. Based on this and previous observations of transgranular stress corrosion characteristics of aus-tenitic stainless steels in chloride environments, a “hydrogen-induced cleavage” model is proposed. This model is essentially a modification of a model based on enhanced structural reactivity associated with Lomer-Cottrell locks proposed by Robertson and Tetelmann in 1962.27
Jupiter and Saturn - Near-infrared spectral albedos

The near-infrared (0.65-2.5 micron) spectral albedo of Jupiter and Saturn with 1.5% spectral resolution is presented for the center of disk and for the limb. There is a distinct difference in the continuum slope between Jupiter and Saturn which may be attributed to a difference in the dust content or composition of the two atmospheres. There is an indication of limb brightening in the deepest CH4 bands on Saturn. No limb brightening is found for Jupiter.
Effect of cholinergic drugs on the brainstem auditory evoked responses (far-field) in rats

Abstract The present studies were undertaken to provide evidence for the presence of cholinergic mechanisms in the modulation of brainstem (far-field) acoustically evoked potentials in rats. A muscarinic agonist, oxotremorine, produces an increase in the amplitudes of such potentials, while administration of nicotine causes amplitude decrement. Physostigmine and carbachol produced a dose-dependent decrement and increment (biphasic) of the amplitudes. In animals pretreated with scopolamine; oxotremorine, physostigmine and carbachol failed to produce an increment of amplitude; on the other hand a decrement of amplitude was observed with these drugs. Similarly pretreatment with mecamylamine blocked the characteristic depressant effects of nicotine and caused an increase in the far-field potential amplitudes. This could be due to the unmasking of opposite cholinergic receptors in the presence of specific muscarinic or nicotinic blockers. These findings suggest the presence of opposing cholinergic influences in the generation of far-field potentials. The possible mechanisms for the muscarinic and nicotinic modulations of these potentials are discussed.
Uncitedness in the biomedical literature

The reception of a scientific article is measured in part by its citedness in the subsequent literature. Although most papers are eventually cited, a number of papers in a variety of scientific disciplines have never been cited. A study was conducted to determine the bibliographic characteristics of uncited papers in the biomedical litterature. It was found that certain bibliographic characteristics differentiate cited from uncited papers
Initial adaptation of Taiwan foreign students to the United States: The impact of prearrival variables

Examined the initial adaptation o f a group of l72 foreign students from Taiwan by utilizing information gathered prior to their departure. A multidimensional model postulated initial postarrival adaptation (i.e., emotional well-being and adjustment) to be related to predeparture emotional well-being, demographics, personality, understanding o f life in the U.S., available resources, and problems anticipated. Higher postarrival depressive level was best predicted by higher prearrival depression in both sexes. For men, it was also significantly predicted by a stronger feminine tendency (i. e., more emotional, sensitive, and affiliative), poorer self-assessment o f English competence, and higher Test o f English as a Foreign Language score; and for women, by anticipating fewer academic problems. Initial adjustment was predicted by higher subjective ratings o f English ability for both sexes; lower feminine tendency and stronger externality (i.e., more outgoing and selfconfident) for men; and availabi6ty o f a larger potential social support network in the U.S. for women. Implications for predeparture interventions to facilitate initial adaptation o f this group are discussed.
Modular, cost-effective, extensible avionics architecture for secure, mobile communications

Current onboard communication architectures are based upon an all-in-one communications management unit. This unit and associated radio systems has regularly been designed as a one-off, proprietary system. As such, it lacks flexibility and cannot adapt easily to new technology, new communication protocols, and new communication links. This paper describes the current avionics communication architecture and provides a historical perspective of the evolution of this system. A new onboard architecture is proposed that allows full use of commercial-off-the-shelf technologies to be integrated in a modular approach thereby enabling a flexible, cost-effective and fully deployable design that can take advantage of ongoing advances in the computer, cryptography, and telecommunications industries.
Prospects for de novo phasing with de novo protein models

The prospect of phasing diffraction data sets `de novo' for proteins with previously unseen folds is appealing but largely untested. In a first systematic exploration of phasing with Rosetta de novo models, it is shown that all-atom refinement of coarse-grained models significantly improves both the model quality and performance in molecular replacement with the Phaser software. 15 new cases of diffraction data sets that are unambiguously phased with de novo models are presented. These diffraction data sets represent nine space groups and span a large range of solvent contents (33–79%) and asymmetric unit copy numbers (1–4). No correlation is observed between the ease of phasing and the solvent content or asymmetric unit copy number. Instead, a weak correlation is found with the length of the modeled protein: larger proteins required somewhat less accurate models to give successful molecular replacement. Overall, the results of this survey suggest that de novo models can phase diffraction data for approximately one sixth of proteins with sizes of 100 residues or less. However, for many of these cases, `de novo phasing with de novo models' requires significant investment of computational power, much greater than 103 CPU days per target. Improvements in conformational search methods will be necessary if molecular replacement with de novo models is to become a practical tool for targets without homology to previously solved protein structures.
Cellulose and xylans in the interface capsule in symbiotic cells of actinorhizae.

Enzyme-gold affinity labeling was used to show that in mature infected cells of actinorhizal symbioses the capsule on the plant host side of the symbiotic interface contained cellulose and xylans. Host species examined for cellulose wereAlnus rubra, Casuarina equisetifolia, C. glauca, Ceanothus cuneata, C. velutinus, Elaeagnus pungens, andMyrica cerifera.. Cellulose was in the capsule throughout the infected cell, implying that during development cellulose synthase was present in the host cell membrane component of the symbiotic interface. Any possible degradation of capsule cellulose by the microsymbiont was either incomplete or transient, because the polymer was present in mature infected cells. Cellulose labeling inCeanothus andElaeagnus was less consistent than in the other species. Dual labeled capsules inCasuarina glauca andAlnus rubra showed a similar distribution of xylans and cellulose. Cytochemical studies indicate that the capsule contains three major classes of cell wall polysaccharides: cellulose, hemicellulose (xylans), and pectins (shown previously). This suggests that the capsule is essentially a thin, internal, tubular plant cell wall.
Rapid elicitation of second messengers by nanomolar doses of triacontanol and octacosanol

Triacontanol (TRIA) increases the dry weight and alters the metabolism of rice (Oryza sativa L.) seedlings within 10 min of application to either the shoots or roots. This activity is prevented if octacosanol (OCTA, C28 primary alcohol) is applied with the TRIA on the roots or shoots. Triacontanol activity is also stopped if the OCTA is applied at least 1 min before the TRIA on the opposite part of the seedling. Triacontanol rapidly elicits a second messenger that moves rapidly throughout the plant resulting in stimulation of growth (dry-weight increase) and water uptake. Octacosanol also produces a second messenger that inhibits TRIA activity. We have named the putative secondary messengers elicited by TRIA and OCTA, TRIM and OCTAM, respectively. The water-soluble TRIM extracted from plants treated with TRIA increases the growth of rice seedlings about 50% more than extracts from untreated plants, within 24 h of application. Both OCTAM and OCTA inhibit the activity of TRIA but not of TRIM. The TRIA messenger was isolated from rice roots within 1 min of a foliar application of TRIA. The TRIM elicited by TRIA will pass through a 4-mm column of water connecting cut rice shoots with their roots and can also be recovered from water in which cut stems of TRIA-treated plants have been immersed. Triacontanol applied to oat (Avena sativa L.) or tomato (Lycopersicon esculentum Mill.) shoots connected to rice roots by a 4-mm water column also results in the appearance of TRIM in rice roots.
Digital subtraction angiography: Applications in otolaryngology: Head and neck surgery

Digital electronic technology has made its most notable contribution to radiology in the form of the CT scanners which have so greatly benefited medical practice. Experience with intravenous angiography using a digital fluoroscopy unit developed at the University of Arizona gives promise of a further major benefit in the area of angiography. The majority of examinations are conducted on an outpatient basis with a risk level comparable to that of an intravenous pyelogram. The authors review their experience with this unit, including it's diagnostic and therapeutic applications to congenital and acquired vascular diseases, neoplasms, and vascular trauma of the head and neck.
Acute and chronic effects of hydrochlorothiazide on vascular adrenergic mechanisms.

The acute and chronic effects of hydrochlorothiazide on adrenergic neuronal and receptor function in the isolated perfused dog mesenteric arteries have been characterized. Hydrochlorothiazide, 2.7 mg/min for 90 min, perfused directly into the arteries, failed to alter adrenergic mechanisms. Chronic oral treatment of dogs with hydrochlorothiazide, 10 mg/kg/day, for 6 months enhanced the frequency-response curve to periaterial nerve syimulation without affecting the vasoconstrictor responses to norepinephrine. However, this effect was no longer observable after an additional 6 months of treatment. Hydrochlorothiazide failed to affect the pharmacological interaction of certain adrenergic agents with sympathetic neuronal and receptor mechanisms. Also, the in vitro accumulation of tritium after incubation with [3H] norepinephrine in atria, ventricle and femoral arterial slices was unaltered by hydrochlorothiazide. The present findings do not support the proposal that hydrochlorothiazide inhibits peripheral sympathetic function.
Science And Faith: New Books with the Same Scepticism

Books reviewed in this article: Richard A. Lee Jr., Science, the Singular, and the Question of Theology Andrew P. Porter, By the Waters of Naturalism: Theology Perplexed Among the Sciences W. Mark Richardson, Robert John Russell, Philip Clayton, and Kirk Wegter–McNelly (eds), Science and the Spiritual Quest: New Essays by Leading Scientists W. Mark Richardson and Gordy Slack (eds), Faith in Science: Scientists Search for Truth
Perceptual Modulation of Motor—But Not Visual—Responses in the Frontal Eye Field during an Urgent-Decision Task

Neuronal activity in the frontal eye field (FEF) ranges from purely motor (related to saccade production) to purely visual (related to stimulus presence). According to numerous studies, visual responses correlate strongly with early perceptual analysis of the visual scene, including the deployment of spatial attention, whereas motor responses do not. Thus, functionally, the consensus is that visually responsive FEF neurons select a target among visible objects, whereas motor-related neurons plan specific eye movements based on such earlier target selection. However, these conclusions are based on behavioral tasks that themselves promote a serial arrangement of perceptual analysis followed by motor planning. So, is the presumed functional hierarchy in FEF an intrinsic property of its circuitry or does it reflect just one possible mode of operation? We investigate this in monkeys performing a rapid-choice task in which, crucially, motor planning always starts ahead of task-critical perceptual analysis, and the two relevant spatial locations are equally informative and equally likely to be target or distracter. We find that the choice is instantiated in FEF as a competition between oculomotor plans, in agreement with model predictions. Notably, although perception strongly influences the motor neurons, it has little if any measurable impact on the visual cells; more generally, the more dominant the visual response, the weaker the perceptual modulation. The results indicate that, contrary to expectations, during rapid saccadic choices perceptual information may directly modulate ongoing saccadic plans, and this process is not contingent on prior selection of the saccadic goal by visually driven FEF responses.
NON-EXISTENCE OF AN EXACT β-CONFIDENCE INTERVAL FOR A SCALE PARAMETER*

There are given k (≥22) independent distributions with c.d.f.'s F(x;θj) indexed by a scale parameter θj, j = 1,…, k. Let θ[i] (i = 1,…, k) denote the ith smallest one of θ1,…, θk. In this paper we wish to show that, under some regularity conditions, there does not exist an exact β-level (0≤β1) confidence interval for the ith smallest scale parameter θi based on k independent samples. Since the log transformation method may not yield the desired results for the scale parameter problem, we will treat the scale parameter case directly without transformation. Application is considered for normal variances. Two conservative one-sided confidence intervals for the ith smallest normal variance and the percentage points needed to actually apply the intervals are provided.
Acid- and Base-Catalyzed D-Glucosylurea Anomerization

Abstract The D-glucosylureas have been found to undergo both acid- and base-catalyzed anomerization. Water was not an effective catalyst for the transformation but the addition of either an acid or base resulted in the formation of an equilibrium mixture. Kinetic investigations of the acid-catalyzed reaction indicated that the key intermediate step was die formation of an iminium ion. A deuterium isotope effect of kH/kD = 0.77 − 0.80 for the acid-catalyzed reactions of either N-β-D-glucopyranosylurea (1) or N.,N′-bis(β-D-glucopyranosyl)urea (3) in both DMF and water excludes an anomerization pathway similar to aldose mutarotation. The lack of significant glucose formation in dilute aqueous acid prior to complete equilibration indicated that the D-glucosyl carbonium ion intermediate was not an important factor. The carbonium ion may, however, contribute to carbohydrate disappearance at high acidity levels. The rate of base-catalyzed anomerization of 3 depended on pH. The transformation resulted in >95% ano...
Heavy-ion beam dynamics in the RIA accelerators

Abstract The Nuclear Science Community in the United States has unanimously concluded that developments in both nuclear science and its supporting technologies make building a Rare-Isotope Accelerator (RIA) facility for production of radioactive beams. The RIA development effort involves several US Laboratories (ANL, JLAB, LANL, LBNL, MSU, ORNL). The RIA project includes a continuous wave 1.4 GV driver linac and a 123 MV post-accelerator, both based on superconducting (SC) cavities operating at frequencies from 48 to 805 MHz. Several new conceptual solutions in physics design of heavy-ion SC linacs have been developed recently. In particular, the concept of multiple charge state beam acceleration in SC linacs was tested and will be used in the driver linac to increase available accelerated beam power. A detailed design has been developed for the focusing–accelerating lattice of the RIA linacs which are configured as an array of short SC cavities, each with independently controllable RF phase. Independent phasing allows the velocity profile to be varied: the linac can be tuned to provide higher energies for the lighter ions. For example, the reference design linac can be tuned to provide a uranium beam at an energy of 403 MeV/u and can be re-tuned to provide a proton beam at 900 MeV. The linac must provide 100 kW beam power with the possibility to upgrade up to 400 kW.
Complement (C5b-9) induces DNA synthesis in rat mesangial cells in vitro.

Complement (C5b-9) induces DNA synthesis in rat mesangial cells in vitro. Background The membrane attack complex C5b-9 causes injury in many forms of immune-mediated glomerular diseases characterized by mesangial cell (MC) proliferation and inhibiting C5b-9 decreases MC proliferation in vivo. Membrane insertion of sublytic quantities of the membrane attack complex of complement (C5b-9) is a potent stimulus for cell activation and the production of a variety of cytokines, growth factors, oxidants, matrix components, and other nephritogenic molecules. In vivo, a common response of MC to C5b-9–mediated injury is cell proliferation, an event closely linked to matrix expansion and sclerosis. In this study, we tested the hypothesis that C5b-9 might also serve as a mitogenic stimulus for MCs. Methods Rat MCs in vitro were exposed anti-Thy1 antibody and 2% normal PVG serum (a complement source) to induce sublytic C5b-9 attack and DNA synthesis and cell number were measured. Control MCs were exposed to antibody and C6-deficient PVG serum. Results Sublytic C5b-9–induced injury to MCs is sufficient to induce DNA synthesis. Furthermore, C5b-9 augmented DNA synthesis induced by platelet-derived growth factor (PDGF) and 5% fetal calf serum. C5b-9–induced DNA synthesis was reduced by inhibiting reactive oxygen species (ROS) with superoxide dismutase and catalase, but not by neutralizing the mitogenic growth factors PDGF and basic fibroblast growth factor (bFGF). Conclusions This study demonstrates that C5b-9 may directly increase DNA synthesis in cultured MCs, which are mediated in part by the release of ROS, and that C5b-9 also augments DNA synthesis induced in MCs by other known mitogens.
Glycomimetics: A Programmed Approach toward Neoglycopeptide Libraries1a

A programmed synthesis of neoglycopeptides has been developed in which two, similar or different, glycoside moieties could be attached either (i) at the N-terminal of short peptides or (ii) one at the N-internal and the other(s) at the N-terminal site, in a highly flexible and controlled manner. A stepwise branching of N-terminal peptides has been achieved by glycoside aldehyde reductive amination followed by the glycoside carboxylic acid coupling (model 1). In another approach, after N-alkylation with glycoside aldehyde, the N-glycosylated derivative is subjected to peptide synthesis. This is then followed by the attachment of the second glycoside moiety at the N-terminal using either glycoside aldehyde or glycoside carboxylic acid derivative (model 2). Alternatively, the attachment of second and third glycoside derivatives could be achieved simultaneously, by reductive amination/carboxylic acid couplings (model 3). The methodologies presented here are highly versatile and combine diversity in both pepti...
A Monte Carlo RSRG method for the percolation/conduction properties of correlated lattices

Abstract A real space renormalization group method for the percolation problem in isotropically and anisotropically correlated systems is proposed. The macroscopic conductive properties at all volume fractions of the conducting phase are computed. It is demonstrated that the anisotropy in the correlation structure of the original lattice has a major effect on its conductive properties. By comparison correlated isotropic lattices have effective conductive properties that differ only slightly from random lattices. Results are presented for binary conductance distributions and for three- and four-component lattices.
Comparative neurochemical and neurobehavioral effects of repeated chlorpyrifos exposures in young and adult rats

Neonatal (7 days old) rats are markedly more sensitive than adults (3 months old) to the acute toxic effects of the insecticide, chlorpyrifos (CPF). In the present study, we have compared the effects of subacute CPF exposures in these same age groups. Repeated doses of CPF (40 mg/kg, SC, every 4 days, total of 4 doses) caused extensive inhibition of cortical, hippocampal, and striatal cholinesterase (ChE) activity in adult rats at 4 (90-92%) and 14 (71-78%) days after the last treatment. Rats treated similarly during postnatal maturation (beginning on day 7) showed a much lower degree of ChE inhibition (21-60%) at these time points. Muscarinic ([3H]quinuclidinyl benzilate, QNB) receptor binding in cortex, hippocampus, and striatum was reduced in adult brain at 4 (30-43%) and 14 (22-32%) days after the final treatment, whereas receptor densities were only marginally affected (5-11% reduction) in young rats. Basal motor activity levels were not affected in either young or adult rats as a function of CPF exposure. CPF-treated adult rats exhibited higher activity levels after challenge with scopolamine (1 mg/kg, IP) at 2, 4, 6, and 8 weeks after treatment, whereas CPF exposure did not affect the motoric response to scopolamine in rats treated during postnatal maturation. These data suggest that although neonatal rats are more sensitive to acute lethal effects from high doses of CPF, adult rats exhibit more persistent neurochemical and neurobehavioral alterations following repeated, lower-level exposures.
A note on extended least squares methods for cluster sampling

Abstract A class of linear models for a two-stage cluster sample is considered. The best linear unbiased predictor of the finite population total can be obtained through extended least squares under these models. The effort of computing the prediction variance of the predictor may be reduced.
Numerical study of an effective interface model for the growth of wetting layers

We present results from a numerical study of an effective interface model introduced by Lipowsky for the growth of wetting layers under complete wetting conditions. Both the equilibrium and the dynamical properties of the model are studied. The values of the scaling exponents are computed when the bulk dimension of the system is either above or below the upper critical dimension. In each case, we find good agreement with the theoretical predictions.
Relationship of baseline fetal heart rate to gestational age and fetal sex

A study of 37 patients who underwent 365 antepartum fetal heart rate tests showed a significant difference in heart rate between 19 to 24 weeks' and 36 to 40 weeks' gestation. Baseline heart rate remained within the normal range, suggesting that an abnormal heart rate at any gestational age should prompt further fetal assessment. Baseline fetal heart rate was not significantly different between male and female fetuses.
Deployment and exploitation of deceptive honeybots in social networks

As social networking sites such as Facebook and Twitter are becoming increasingly popular, a growing number of malicious attacks, such as phishing and malware, are exploiting them. Among these attacks, social botnets have sophisticated infrastructure that leverages compromised user accounts, known as bots, to automate the creation of new social networking accounts for spamming and malware propagation. Traditional defense mechanisms are often passive and reactive to non-zero-day attacks. In this paper, we adopt a proactive approach for enhancing security in social networks by infiltrating botnets with honeybots. We propose an integrated system named SODEXO which can be interfaced with social networking sites for creating deceptive honeybots and leveraging them for gaining information from botnets. We establish a Stackelberg game framework to capture strategic interactions between honeybots and botnets, and use quantitative methods to understand the tradeoffs of honeybots for their deployment and exploitation in social networks. We design a protection and alert system that integrates both microscopic and macroscopic models of honeybots and optimally determines the security strategies for honeybots. We corroborate the proposed mechanism with extensive simulations and comparisons with passive defenses.
Flexibility of collagen determined from dilute solution viscoelastic measurements.

The frequency dependences of the storage and loss shear moduli, G′ and G″, of pronase-treated collagen dissolved in acetate buffer at pH 4.0 were measured at 17.0°C by use of the Birnboim-Schrag multiple lumped resonator apparatus. Some of the solutions contained 70% glycerol. The infinite-dilution moduli were determined and compared with theoretical models for a rigid cylinder and a semiflexible rod. Only the latter could fit the data. A rotational time of 144 μs and a slowest flexural relaxation time of 21 μs, both reduced to water at 20°C, were determined from the fit. The intrinsic viscosity and rotational relaxation time correspond to a semiflexible rod with persistence length of about 170 nm and a Young's modulus of 4 × 1010 dyn/cm2.
Spin dependence in He(2(3)S) metastable-atom deexcitation at magnetized Fe(110) and O/Fe(110) surfaces.

Spin-labeling techniques, specifically the use of electron-spin-polarized He(${2}^{3}$S) metastable atoms coupled with analysis of the number and spin of the ejected electrons, are used to investigate the dynamics of metastable-atom--surface interactions and the properties of (magnetized) Fe(110) and O/Fe(110) surfaces. The data show that the dominant He(${2}^{3}$S) metastable-atom deexcitation mechanism at such surfaces is resonance ionization followed by Auger neutralization, and that the ejected-electron polarization reflects the iron conduction-band polarization. The present results, when interpreted using the theory of Penn and Apell, also indicate that the magnetization in the vacuum above a clean Fe(110) surface at distances (\ensuremath{\sim}3--5 \AA{}) where Auger neutralization occurs is negative but changes sign upon exposure to oxygen. Several possible explanations for this sign reversal are discussed. The measurements establish spin-polarized metastable-atom deexcitation spectroscopy as an extraordinarily sensitive probe of the surface magnetic environment.
Additional Construct Validity Evidence for the Task/Contextual Performance Distinction

Borman and Motowidlo (1993) hypothesized two job performance domains labeled task performance and contextual performance. Previous research has provided construct validity evidence in the form of differential predictor-criterion relations for the two performance domains. This study provided additional construct validity evi- dence. I examined internal consistency and empirical independence of the two domains by analyzing multitrait-multirater (MTMR) matrices. Confirmatory factor analyses (CFAs) of 15 MTMR matrices showed higher correlations for performance dimensions within a domain (mean correlations were .70 and .70 for task and contextual performance, respectively) than between domains (M = 3). Evidence showed that the distinction between task and contextual performance was more clear for nonmanagerial than for managerial jobs. One aspect of contextual performance, cooperating with others, showed greater independence from task performance than did persisting with extraeffort or following organizational...
Medicare Part B reimbursement and the perceived quality of physician care.

The maximum amount physicians can charge Medicare patients for Part B services depends on Medicare reimbursement rates and on federal and state restrictions regarding balance billing. This study evaluates whether Part B payment rates, state restrictions on balance billing beyond the federal limit, and physician balance billing influence how beneficiaries rate the quality of their doctor’s care. Using nationally representative data from the 2001 to 2003 Medicare Current Beneficiary Survey, this paper finds strong evidence that Medicare reimbursement rates, and state balance billing restrictions influence a wide range of perceived care quality measures. Lower Medicare reimbursement and restrictions on physicians’ ability to balance bill significantly reduce the perceived quality of care under Part B.
A new twist on the Marcum Q-function and its application

A new form of the Marcum (1950) Q-function is presented that has both computational and analytical advantages. The new form is particularly useful in simplifying and rendering more accurate the analysis of the error probability performance of uncoded and coded partially coherent, differentially coherent, and noncoherent communication systems in the presence of fading. It also enables simple upper and lower bounds to be found analogous to the Chernoff bound on the Gaussian Q-function.
Evidence that GTP-binding domain but not catalytic domain of transglutaminase 2 is essential for epithelial-to-mesenchymal transition in mammary epithelial cells.

Introduction The expression of proinflammatory protein tissue transglutaminase 2 (TG2) is frequently upregulated in multiple cancer cell types. However, the exact role of TG2 in cancer cells is not well-understood. We recently initiated studies to determine the significance of TG2 in cancer cells and observed that sustained expression of TG2 resulted in epithelial-to-mesenchymal transition (EMT) and promoted cancer stem cell (CSC) traits in mammary epithelial cells. These results suggested that TG2 could serve as a promising therapeutic target for overcoming chemoresistance and inhibiting metastatic spread of cancer cells.
In vivo strains in the femur of the Virginia opossum (Didelphis virginiana) during terrestrial locomotion: testing hypotheses of evolutionary shifts in mammalian bone loading and design

SUMMARY Terrestrial locomotion can impose substantial loads on vertebrate limbs. Previous studies have shown that limb bones from cursorial species of eutherian mammals experience high bending loads with minimal torsion, whereas the limb bones of non-avian reptiles (and amphibians) exhibit considerable torsion in addition to bending. It has been hypothesized that these differences in loading regime are related to the difference in limb posture between upright mammals and sprawling reptiles, and that the loading patterns observed in non-avian reptiles may be ancestral for tetrapod vertebrates. To evaluate whether non-cursorial mammals show loading patterns more similar to those of sprawling lineages, we measured in vivo strains in the femur during terrestrial locomotion of the Virginia opossum (Didelphis virginiana), a marsupial that uses more crouched limb posture than most mammals from which bone strains have been recorded, and which belongs to a clade phylogenetically between reptiles and the eutherian mammals studied previously. The presence of substantial torsion in the femur of opossums, similar to non-avian reptiles, would suggest that this loading regime likely reflects an ancestral condition for tetrapod limb bone design. Strain recordings indicate the presence of both bending and appreciable torsion (shear strain: 419.1±212.8 μe) in the opossum femur, with planar strain analyses showing neutral axis orientations that placed the lateral aspect of the femur in tension at the time of peak strains. Such mediolateral bending was unexpected for a mammal running with near-parasagittal limb kinematics. Shear strains were similar in magnitude to peak compressive axial strains, with opossum femora experiencing similar bending loads but higher levels of torsion compared with most previously studied mammals. Analyses of peak femoral strains led to estimated safety factor ranges of 5.1–7.2 in bending and 5.5–7.3 in torsion, somewhat higher than typical mammalian values for bending, but approaching typical reptilian values for shear. Loading patterns of opossum limb bones therefore appear intermediate in some respects between those of eutherian mammals and non-avian reptiles, providing further support for hypotheses that high torsion and elevated limb bone safety factors may represent persistent ancestral conditions in the evolution of tetrapod limb bone loading and design.
Class-action lawsuits medicine's newest legal headache

The legal news for Canada's physicians has been bleak for years: 1 in 25 physicians was named in a new legal action in 2000 and the number of malpractice cases proceeding to trial doubled between 1995 and 1999. Now, the country's first medical malpractice class-action lawsuits give them something
(18)F-labeled Positron Emission Tomographic Radiopharmaceuticals in Oncology: An Overview of Radiochemistry and Mechanisms of Tumor Localization

Molecular imaging is the visualization, characterization, and measurement of biological processes at the molecular and cellular levels in a living system. At present, positron emission tomography/computed tomography (PET/CT) is one the most rapidly growing areas of medical imaging, with many applications in the clinical management of patients with cancer. Although [(18)F]fluorodeoxyglucose (FDG)-PET/CT imaging provides high specificity and sensitivity in several kinds of cancer and has many applications, it is important to recognize that FDG is not a "specific" radiotracer for imaging malignant disease. Highly "tumor-specific" and "tumor cell signal-specific" PET radiopharmaceuticals are essential to meet the growing demand of radioisotope-based molecular imaging technology. In the last 15 years, many alternative PET tracers have been proposed and evaluated in preclinical and clinical studies to characterize the tumor biology more appropriately. The potential clinical utility of several (18)F-labeled radiotracers (eg, fluoride, FDOPA, FLT, FMISO, FES, and FCH) is being reviewed by several investigators in this issue. An overview of design and development of (18)F-labeled PET radiopharmaceuticals, radiochemistry, and mechanism(s) of tumor cell uptake and localization of radiotracers are presented here. The approval of clinical indications for FDG-PET in the year 2000 by the Food and Drug Administration, based on a review of literature, was a major breakthrough to the rapid incorporation of PET into nuclear medicine practice, particularly in oncology. Approval of a radiopharmaceutical typically involves submission of a "New Drug Application" by a manufacturer or a company clearly documenting 2 major aspects of the drug: (1) manufacturing of PET drug using current good manufacturing practices and (2) the safety and effectiveness of a drug with specific indications. The potential routine clinical utility of (18)F-labeled PET radiopharmaceuticals depends also on regulatory compliance in addition to documentation of potential safety and efficacy by various investigators.
Adjuvant radiotherapy for phyllodes tumor of breast

Our purpose was to examine the role of radiotherapy in the management of phyllodes tumor of the breast. Eight patients were treated with adjuvant radiotherapy for nonmetastatic phyllodes tumor of the breast at the M.D. Anderson Cancer Center between December 1988-August 1993. Tumors were classified as benign (n=2), borderline (indeterminate; n=1), or malignant (n=5). Median follow-up was 36.5 months. Primary surgery consisted of either lumpectomy in 2 patients or mastectomy in 6 patients. Seven patients received adjuvant radiation therapy to the breast or chest wall to a dose of 60 Gy. One patient received 50 Gy to the breast, followed by an interstitial boost of 20 Gy for a total of 70 Gy. Radiotherapy was administered for a combination of reasons, including bulky tumor volume, positive margins, recurrence, and/or malignant histology. There were no local or distant failures. This retrospective review suggests that adjuvant radiotherapy may be underutilized in the treatment of phyllodes tumor of the breast, particularly in patients with adverse features. Although treatment to the breast or chest wall (not the lymphatics) to a dose of 60 Gy appears effective, a dose-response has not been established, and lower doses (50-60 Gy) may be equally effective.
The Complexity of Optimal Queuing Network Control

We show that several well-known optimization problems related to the optimal control of queues are provably intractable-independently of any unproven conjecture such as P â NP. In particular, we show that several versions of the problem of optimally controlling a simple network of queues with simple arrival and service distributions and multiple customer classes is complete for exponential time. This is perhaps the first such intractability result for a well-known optimization problem. We also show that the restless bandit problem the generalization of the multi-armed bandit problem to the case in which the unselected processes are not quiescent is complete for polynomial space.
Target detection for passive radar with noisy reference channel

This paper considers the problem of target detection in a passive radar consisting of a reference channel (RC) and a surveillance channel (SC). The RC receives an unknown source signal directly transmitted by a non-cooperative illuminator of opportunity (IO), whereas the SC collects target echoes due to the illumination by the same IO. The conventional solution to this passive detection problem is a cross-correlation (CC) based detector that cross-correlates the reference signal from the RC and the surveillance signal from the SC. It is known that the CC detector is very sensitive to the noise level in the RC. In this paper, we develop four detection algorithms based on the generalized likelihood ratio test principle, by treating the unknown source signal from the IO to be deterministic or stochastic and under conditions whether the noise variance is known or unknown. Our results demonstrate that when the reference signal is noisy, three of the proposed detectors offer significant improvements in detection performance over the CC detector.