cssi/SciSciGPT-SciSciNet huggingface dataset:
A quasiclassical trajectory study of the reaction H + O2 OH + O with the O2 reagent vibrationally excited.

Quasiclassical trajectories have been computed on the Melius−Blint (MB) Potential Energy Surface (PES) and on the Double Many-Body Expansion (DMBE) IV PES of Pastrana et al. describing the H + O2 ⇔ OH + O reaction with the nonrotating (J = 0) O2 reagent vibrationally excited to levels v = 6, 7, 8, 9, and 10 at four temperatures: 1000, 2000, 3000, and 4000 K. The vibrational energy levels were selected by using a semiclassical Einstein−Brillouin−Keller (EBK) quantization procedure while the relative translational energy was sampled from a Boltzmann weighted distribution. The rate coefficient for the formation of the OH + O products is seen to increase monotonically with quantum number and nearly monotonically with temperature. On the MB PES, at T = 1000 K, the total rate coefficient increases by a factor of 5.2 as the initial vibrational quantum number of the O2 diatom increases from v = 6 to v = 10. For T = 2000 K, this factor drops to 3.3, to 2.9 for T = 3000 K, and to 2.5 for T = 4000 K. On the DMBE IV...
Towards a Minimal Cytoplasm

Cytoplasm is common to all living cells and is increasingly recognized for its active role in facilitating and regulating intracellular reactions. Models for the crowded, dynamic, and compartmentalized cytoplasm should therefore be ­considered for incorporation in minimal cells. This chapter begins with an ­introduction to biological cytoplasm and then describes several approaches to ­primitive models of the intracellular environment. Key aspects of the ­cytoplasm that have been incorporated in model systems thus far include restricted ­volumes, ­macromolecular crowding, and colocalization or compartmentation of ­biomolecular components.
Cr(VI) occurrence and geochemistry in water from public-supply wells in California

Hexavalent chromium, Cr(VI), in 918 wells sampled throughout California between 2004 and 2012 by the Groundwater Ambient Monitoring and Assessment-Priority Basin Project (GAMA-PBP) ranged from less than the study reporting limit of 1 microgram per liter (μg/L) to 32 μg/L. Statewide, Cr(VI) was reported in 31 percent of wells and equaled or exceeded the recently established (2014) California Maximum Contaminant Level (MCL) for Cr(VI) of 10 μg/L in 4 percent of wells. Cr(VI) data collected for regulatory purposes overestimated Cr(VI) occurrence compared to spatially-distributed GAMA-PBP data. Ninety percent of chromium was present as Cr(VI), which was detected more frequently and at higher concentrations in alkaline (pH ≥ 8), oxic water; and more frequently in agricultural and urban land uses compared to native land uses. Chemical, isotopic (tritium and carbon-14), and noble-gas data show high Cr(VI) in water from wells in alluvial aquifers in the southern California deserts result from long groundwater-residence times and geochemical reactions such as silicate weathering that increase pH, while oxic conditions persist. High Cr(VI) in water from wells in alluvial aquifers along the west-side of the Central Valley results from high-chromium in source rock eroded to form those aquifers, and areal recharge processes (including irrigation return) that can mobilize chromium from the unsaturated zone. Cr(VI) co-occurred with oxyanions having similar chemistry, including vanadium, selenium, and uranium. Cr(VI) was positively correlated with nitrate, consistent with increased concentrations in areas of agricultural land use and mobilization of chromium from the unsaturated zone by irrigation return.
Mechanisms of action of adrenal medulla grafts: the possible role of peripheral and central dopamine systems.

Publisher Summary This chapter examines the mechanisms of action of adrenal medulla grafts. Adrenal medulla grafts reduce rotational behavior induced by both amphetamine (AMPH) and apomorpbine (APO) in animals with unilateral dopamine (DA)-denervation. The peripheral administration of DA increases extracellular striatal DA concentrations adjacent to adrenal medulla grafts, suggesting an impairment of the blood–brain barrier by the grafts. This change in extracellular DA is slight in animals with no behavioral change, modest in animals with decreased APO-induced rotation, and marked (about 10-fold) in animals with decreased AMPH-induced rotation. Changes in serum catecholamines are correlated with the decrease in APO-induced rotations following adrenal medulla grafts. The specific correlations depend upon whether the animal is adrenodoxin (ADX) or not. Adrenal chromaffin cell survival is not correlated with serum catecholamines or behavioral changes. The number of surviving chromaffin cells is small and inconsistent. Behavioral recovery (decreased APO-induced rotation) is associated with an increased symmetry of striatal extracellular DA and dihydroxyphenylacetic acid (DOPAC) concentrations as determined by microdialysis. This increased symmetry appears to be related in part to increases in DA and DOPAC concentrations on the lesioned side but also in part to decreases in DA and DOPAC concentrations on the normal, unlesioned, and ungrafted side.
Mammography registered tactile imaging

Breast cancer and other breast pathologies often manifest as an area of increased tissue stiffness. The gold standard for breast cancer screening is mammography, which records the radioopacity of tissues in the breast, and therefore depends on factors other than stiffness. Tactile imaging uses an array of pressure sensors to noninvasively record the palpable extent of breast tissue stiffness. Tactile imaging quantifies palpation, and holds promise for increasing the positive predictive value of screening mammography by highlighting areas of abnormal stiffness. We propose a method for registering tactile images obtained in the same plane and immediately after the corresponding mammogram. A finite element model-based approach is presented which is used to account for the spreading of the breast tissue induced by the mammographic compression that is not present in obtaining the tactile image. We devise an algorithm that can register the modeled tactile images to within 6% of the modeled mammograms for breasts of varying size and stiffness. Clinical mammograms and tactile images were collected on 11 subjects, and the registration algorithm applied to the images. The registered tactile images and mammograms correlate well over stiff, radioopaque areas such as glandular and fibrous tissue, and highlight areas of increased stiffness not indicated by the mammogram alone.
Key pathways regulated by HoxA9,10,11/HoxD9,10,11 during limb development

The 39 mammalian Hox genes show problematic patterns of functional overlap. In order to more fully define the developmental roles of Hox genes it is necessary to remove multiple combinations of paralogous and flanking genes. In addition, the downstream molecular pathways regulated by Hox genes during limb development remain incompletely delineated. In this report we examine limb development in mice with frameshift mutations in six Hox genes, Hoxa9,10,11 and Hoxd9,10,11. The mice were made with a novel recombineering method that allows the simultaneous targeting of frameshift mutations into multiple flanking genes. The Hoxa9,10,11 −/− /Hoxd9,10,11 −/− mutant mice show a reduced ulna and radius that is more severe than seen in Hoxa11 −/−/Hoxd11 −/− mice, indicating a minor role for the flanking Hox9,10 genes in zeugopod development, as well as their primary function in stylopod development. The mutant mice also show severe reduction of Shh expression in the zone of polarizing activity, and decreased Fgf8 expression in the apical ectodermal ridge, thereby better defining the roles of these specific Hox genes in the regulation of critical signaling centers during limb development. Importantly, we also used laser capture microdissection coupled with RNA-Seq to characterize the gene expression programs in wild type and mutant limbs. Resting, proliferative and hypertrophic compartments of E15.5 forelimb zeugopods were examined. The results provide an RNA-Seq characterization of the progression of gene expression patterns during normal endochondral bone formation. In addition of the Hox mutants showed strongly altered expression of Pknox2, Zfp467, Gdf5, Bmpr1b, Dkk3, Igf1, Hand2, Shox2, Runx3, Bmp7 and Lef1, all of which have been previously shown to play important roles in bone formation. The recombineering based frameshift mutation of the six flanking and paralogous Hoxa9,10,11 and Hoxd9,10,11 genes provides a resource for the analysis of their overlapping functions. Analysis of the Hoxa9,10,11 −/− /Hoxd9,10,11 −/− mutant limbs confirms and extends the results of previous studies using mice with Hox mutations in single paralogous groups or with entire Hox cluster deletions. The RNA-Seq analysis of specific compartments of the normal and mutant limbs defines the multiple key perturbed pathways downstream of these Hox genes.
Universal Power Law Governing Pedestrian Interactions

Human crowds often bear a striking resemblance to interacting particle systems, and this has prompted many researchers to describe pedestrian dynamics in terms of interaction forces and potential energies. The correct quantitative form of this interaction, however, has remained an open question. Here, we introduce a novel statistical-mechanical approach to directly measure the interaction energy between pedestrians. This analysis, when applied to a large collection of human motion data, reveals a simple power-law interaction that is based not on the physical separation between pedestrians but on their projected time to a potential future collision, and is therefore fundamentally anticipatory in nature. Remarkably, this simple law is able to describe human interactions across a wide variety of situations, speeds, and densities. We further show, through simulations, that the interaction law we identify is sufficient to reproduce many known crowd phenomena. Language: en
Thalamocortical axons extend along a chondroitin sulfate proteoglycan- enriched pathway coincident with the neocortical subplate and distinct from the efferent path

The distinct axonal tracts of the mature nervous system are defined during development by sets of substrate-bound and diffusible molecular signals that promote or restrict axonal elongation. In the adult cerebral cortex, efferent and afferent axons are segregated within the white matter. To define the relationship of growing efferent and afferent axons in the developing murine cortex to chondroitin sulfate proteoglycans (CSPGs) in the pericellular and extracellular matrix, we used the fluorescent tracer Dil to determine axonal trajectories and immunolabeling to disclose the distribution of CSPGs. Axons of neurons in the preplate are the first to leave the cortex; they arise in the CSPG-rich preplate and extend obliquely across it to enter the CSPG-poor intermediate zone. Slightly later, axons of cortical plate neurons extend directly across the CSPG-rich subplate, and then turn abruptly to run in the upper intermediate zone. In contrast, once afferent axons from the thalamus reach the developing cortical wall, their intracortical trajectory is centered on the CSPG-rich subplate, above the path taken by efferent axons. Our findings demonstrate a molecular difference between the adjacent but distinct efferent and afferent pathways in developing neocortex. Early efferents cross the subplate and follow a pathway that contains very little CSPG, while afferents preferentially travel more superficially within the CSPG-rich subplate. Thus, CSPGs and associated extracellular matrix (ECM) components in the preplate/subplate do not form a barrier to axonal initiation or outgrowth in the neocortex as they may in other locations. Instead, their distribution suggests a role in defining discrete axonal pathways during early cortical development.
Implementing particle filters with Metropolis-Hastings algorithms

A particle filter deals with state estimation problem or nonlinear models with non-Gaussian noise. In the framework of a particle filter, a resampling scheme is used to decrease the degeneracy phenomenon, however it also introduces the problem or sample impoverishment, which can be reduced by using the Markov Chain Monte Carlo (MCMC) method, such as the Metropolis-Hastings (M-H) algorithm. However, there are many possible choices within the family of M-H algorithms, and the performance of particle filters with MCMC moves is closely related to the choice of the M-H algorithm. This paper discusses the implementation of a particle filter with various M-H algorithms. A numerical example is presented, and the simulation results are given for discussion.
Increasing parental participation during rounds in a pediatric cardiac intensive care unit.

Background Inviting parents of sick children to participate during the rounding process may reduce parents' anxiety and improve communication between the parents and the health care team. Objectives To increase the percentage of available parents invited to participate in morning rounds in a pediatric cardiothoracic intensive care unit (CTICU). Methods Invitations to parents to participate in morning CTICU rounds were randomly audited from June 2012 to April 2014 (mean, 15 audits per month). From June 2012 to February 2013 (before intervention), 73% of parents available during morning rounds received an invitation to participate. From April 2013 to May 2013, the following interventions (family participation bundle) were implemented: (1) staff education, (2)"Invitation to Rounds" handout added to the parent welcome packet with verbal explanation, (3) bedside tool provided for parents to communicate desire to participate in rounds with the team, (4) reminder to invite parents added to nursing rounding sheet. Following interventions, family feedback was obtained by 1-on-1 (physician-parent) open-ended conversation. Results From April 2013 to April 2014, 94% of parents available during morning rounds received an invitation to participate. Reasons for not participating: chose not to participate (63%), sleeping-staff reluctant to wake (25%), not English speaking (7%), breastfeeding (5%). Conclusion Implementation of a family participation bundle was successful in increasing invitations to parents to participate during morning rounds in the CTICU. Engagement of staff and addressing specific staff concerns was instrumental in the project's success.
The Devil you Know: Pegs vs Floats with Uncertain Outcomes

Theory predicts that a fixed exchange rate regime will be abandoned after a sizable economic shock as currency devaluation could stimulate exports and output. However, devaluation is risky as the new level of the exchange rate and the rate of inflation cannot be predicted. We show that this uncertainty creates resistance to devaluation. Policymakers prefer to maintain the fixed exchange rate and to undergo internal adjustment. We illustrate the point theoretically and provide supporting evidence from Bulgaria's currency board.
Microstructural Development and Mechanical Properties for Reactive Air Brazing of ZTA to Ni Alloys Using Ag ? CuO Braze Alloys

Reactive air brazing (RAB) is a potential joining technique to join metal alloys to ceramics for a variety of applications. In the current study, nickel (Ni) alloys were heat treated to form an oxide layer prior to RAB joining to zirconia toughened alumina (ZTA). The Ni alloys evaluated were Nicrofer 6025 HT, Inconel 600, Inconel 693, Haynes 214 and Inconel 601. The ZTA studied had compositions of 0 to 15 wt% zirconia and 0 to 14 wt% glass. Four point-bend tests were performed to evaluate the joint strength of ZTA/ZTA and ZTA/nickel alloys brazed with Ag-2wt% CuO braze alloys. It was determined that the joint strength is not a function of the ZTA composition, but that the strength is a strong function of the chemistry and microstructure of the oxide layer formed on the nickel alloy. It was determined that an increase in the aluminum content of the Ni alloy resulted in an increase of the thickness of alumina in the oxide layer and was directly proportional to the bond strength with the exception of Inconel 601 which exhibited relatively high joint strengths even though it had a relatively low aluminum content.
Tobacco and alcohol use-prevention program for Hispanic migrant adolescents.

Abstract Objectives Evaluate a community-based tobacco/alcohol use–prevention program group compared with an attention-control condition (first aid/home safety) group. Methods A total of 660 adolescents and 1 adult caregiver for each were recruited through the Migrant Education Program to participate in an 8-week intervention. Random assignment to the two groups occurred in 22 schools. Seventy 8-week intervention groups (37 tobacco/alcohol and 33 attention-control) were conducted. Assessments occurred at baseline, immediate post-intervention, and 1- and 2-year follow-ups. Susceptibility to smoking and alcohol as well as smoking and drinking over the past 30 days were the primary outcomes of interest. Results Following intervention, no between-group differences in smoking or drinking were significant. Thirty-day smoking started and remained at very low levels, with the highest group prevalence at any measurement period being 4.7% and the lowest 2.5%. Those considered susceptible to smoking dropped by nearly 40% in the attention-control group and by 50% in the intervention group from baseline to the final follow-up. (The overall reduction from post-test to final follow-up was statistically significant.) Less-acculturated children were less likely to report drinking in the past 30 days. Conclusions The current intervention was not demonstrated to be effective in preventing cigarette or alcohol consumption. This perhaps is due to very low baseline levels of smoking and drinking in the migrant youth participants.
Proton-threshold states in 28Si☆

Abstract The 27 Al( 3 He, d) 28 Si reaction has been used to locate candidates for resonances in the 27 Al + p system residing near the proton-capture threshold in the energy region characteristic of quiescent stellar hydrogen burning. Two such states are observed at excitation energies E x = 11.658 MeV( J π = 2 + ) and 11.671 MeV ( J π = 1 − ). A comparison of the cross sections for the 27 Al( 3 He, d) 28 Si and the 27 Al(α, t) 28 Si reactions implies angular-momentum transfers of l = 2 and l = 3, respectively, for the two states of interest. Using this result, an astrophysically significant upper limit on the thermonuclear reaction rate has been calculated for the 27 Al(p, γ) 28 Si reaction which is found to be too slow to affect the 27 Al abundance in red giants.
Ethics Case-Study Simulation: A Generic Tool for Psychology Teachers.

A case-study simulation program designed to assist instructors in teaching ethics in psychology is described. The program is generic, allowing instructors to develop their own case studies to use w...
Outcome of adenotonsillectomy for obstructive sleep apnea in obese and normal-weight children

OBJECTIVES: 1) To evaluate the relative severity of obstructive sleep apnea (OSA) in obese and normal-weight children; 2) to compare changes in respiratory parameters after adenotonsillectomy in obese and normal-weight children.STUDY DESIGN AND SETTING: Prospective controlled trial that included children aged 3 to 18 years. All study participants underwent pre- and postoperative polysomnography.RESULTS: The study population included 33 obese children and 39 normal-weight controls. Preoperatively, the median obstructive apnea-hypopnea index (AHI) was 23.4 (range 3.7-135.1) for obese and 17.1 (range 3.9-36.5) for controls (P < 0.001). Postoperatively, the AHI was 3.1 (range 0-33.1) for obese and 1.9 (range 0.1-7.0) for controls (P < 0.01). Twenty-five obese children (76%) and 11 controls (28%) had persistent OSA.CONCLUSION AND SIGNIFICANCE: AHI scores are higher in obese than in normal-weight children with OSA. Both groups show a dramatic improvement in AHI after adenotonsillectomy, but persistent OSA is mo...
Time-domain analysis of ultrasonic reflection from imperfect interfaces

The specular reflection of ultrasound from defect covered bond planes is analyzed in the time-domain using the independent scattering model for incident plane waves. We hypothesize that the early-time asymptotics of the reflected wave are given exactly by the independent scattering model for waves that are normally incident on the bond plane. For non-normal incidence, a more restricted result is available for reflected longitudinal waves. We present theoretical arguments for the plausibility of the hypothesis. Experimental measurements made on two sets of model bond planes test and support the hypothesis. Our motivations are as follows. An effort is underway to develop nondestructive methods for estimating the integrity of metal-metal bonds. These methods primarily focus on the reflection of ultrasound in the long wavelength limit, where one can estimate an effective elastic constant. People have characterized the overall quality of the bond in terms of this elastic constant. However, one cannot in this way infer more detailed information such as the average size of the defects or their area fraction. Higher frequency probes, which do provide more detailed information, have been studied in the independent scattering model. Consequently, we have (1) extended the independent scattering model to the time-domain, and (2) shown that it is asymptotically correct for early-time reflections from a defect covered plane (the bond plane). We expect that time-domain methods, based on the analysis presented in this paper, will form the basis for a more rigorous technique for determining the area fraction and the average defect size.
Video streaming over overlaid bluetooth piconets (OBP)

In a large scale Bluetooth network, scatternet has been regarded as the only interconnection method among piconets. But, most Bluetooth devices do not support scatternet connection. Moreover, in high mobility situations, scatternet is not useful because of frequent disconnections and reconnections. Overlaid Bluetooth Piconets (OBP) interconnects piconets and forms a virtual scatternet. This demo shows the possibility of using OBP instead of Scatternet for Video Streaming.
MediaBench II video: expediting the next generation of video systems research

The first step towards the design of video processors and video systems is to achieve an accurate understanding of the major video applications, including not only the fundamentals of the many video compression standards, but also the workload characteristics of those applications. Introduced in 1997, the MediaBench benchmark suite provided the first set of full application-level benchmarks for studying video processing characteristics, and has consequently enabled significant research in computer architecture and compiler research for multimedia systems. To expedite the next generation of systems research, the MediaBench Consortium is developing the MediaBench II benchmark suite, incorporating benchmarks from the latest multimedia technologies, and providing both a single composite benchmark suite as well as separate benchmark suites for each area of multimedia. In the area of video, MediaBench II Video includes both the popular mainstream video compression standards, such as Motion-JPEG, H.263, and MPEG-2, and the more recent next-generation standards, including MPEG-4, Motion-JPEG2000, and H.264. This paper introduces MediaBench II Video and provides a comprehensive workload evaluation of its major processing characteristics.
Chronoamperometry of surface-confined redox couples. Application to daunomycin adsorbed on hanging mercury drop electrodes

Abstract The electrochemistry of daunomycin adsorbed on a hanging mercury drop electrode (HMDE) was studied in aqueous pH 9.18 phosphate buffer solution. At potentials positive of the formal potential ( E °′=−0.73 V vs. SCE), bilayer formation was indicated, while at negative potentials, a less densely packed monolayer was formed. A novel differential chronoamperometric kinetic analysis, which explicitly took into account solution IR drop, indicated that a two-electron ECE pathway was followed for the cathodic reaction. The mechanism and associated kinetic parameters were also in agreement with the cyclic voltammetry. The chemical step, which was assigned to protonation of the semiquinone radical anion, was assumed to be at equilibrium. In Appendix A , the transient response of the simple Randles equivalent circuit to a potential step excitation function is derived.
Polyimide solution properties

Solution characterization measurements indicate that cylization of the polyamic acid from 2,4-diaminoisopropylbenzene and pyromellitic dianhydride (PMDA) to the polyimide can be effected with small change in number-average degree of polymerization. An increase in weight-average molecular weight on conversion to polyimide is attributed to branching side reactions. Inherent viscosities of polyimides from 4,4′-diaminodiphenyl ether and PMDA decreased slowly with time in concentrated (97%) sulfuric acid, probably as a result of hydrolytic cleavage. The zero-time viscosity intercepts were related to both the precursor and the estimated polyimide molecular weight. The latter gave ηinh (c = 0.5% solids) = 2.76 × 10−3M0.53w for 60,000 < Mw < 300,000. The exponent is near the lower limit of 0.5 found in theta solvents. The characteristic ratio of the root-mean-square end-to-end distance of a chain to the square root of its molecular weight is 1.1 A and the steric factor is 1.1; these results suggest that the unperturbed polyimide chain is almost as extended as an equivalent freely rotating chain, a general feature of long-bonded polymers with p-phenylene rings in the chain backbone.
Synthesis of a cytosine nucleoside of 2-amino-2-deoxy-β-D-xylofuranose

Abstract 1-(2-Amino-2-deoxy-β-D-xylofuranosyl)cytosine (13) was synthesized by three routes: (a) coupling of 2-deoxy-3,5-di-O-p-nitrobenzoyl-2-(trifluoroacetamido)-D- xylofuranosyl chloride (5) with 2,4-dimethoxypyrimidine and subsequent treatment with methanolic ammonia (b) coupling of 5 with 4-N-acetyl-2-O,4-N-bis(trimethylsilyl)cytosine followed by treatment with methanolic ammonia, and (c) thiation of 1-[3,5-di-O-acetyl-2-deoxy-2-(triflouroacetamido)-β-D-xylofuranosyl]uracil (6) by treatment with phosphorus pentasulfide in pyridine followed by amination of the resulting 4-thionucleoside 12 with methanolic ammonia. The best yield was obtained via route (a).
Metabolism of dimethylnitrosamine and subsequent removal of O6-methylguanine from DNA by isolated rat hepatocytes

Abstract Freshly prepared isolated hepatocytes were shown to metabolize dimethylnitrosamine producing an alkylating agent which reacted with cellular DNA giving rise to 7-methylguanine and O6-methylguanine. Alkylation of DNA was prevented by aminoacetonitrile and was proportional to the dimethylnitrosamine concentration over the range of 1–90 μM. Isolated hepatocytes were able to catalyze the removal of O6-methylguanine from their DNA. After formation of this product by reaction with N-methyl-N-nitrosourea or dimethylnitrosamine to give extents of alkylation in the range of 0.1–15.0 μmol O6-methylguanine per mole of guanine in DNA, the loss produced in 3 h incubation was comparable to that seen in vivo from liver DNA alkylated to the same extent. The isolated hepatocytes therefore, provide a useful system in which factors influencing O6-methylguanine persistence in DNA can be studied.
REACHING ASYMPTOTIC EFFICIENT PERFORMANCE FOR SQUARED PROCESSING OF RANGE AND RANGE DIFFERENCE LOCALIZATIONS IN THE PRESENCE OF SENSOR POSITION ERRORS

Computationally efficient source location solutions from TOAs or TDOAs require the squaring of the measurements before optimization. The squaring operation changes the characteristics of the measurements and causes degradation in the localization accuracy, unless proper weightings are applied when forming the cost function for minimization. The previously developed weighting values are useful for measurements with accurate sensor positions only. This paper extends the study and derives the weightings when the sensor position uncertainties are present such as in sensor networks. The resultant cost functions for TOA and TDOA positionings are analyzed and the performance accuracy is shown to attain the CRLB asymptotically under Gaussian noise. Simulations validate the performance of the new cost functions and the theoretical investigations.
Fibrillar Growth in Polyaniline

Large, colorless aggregates are observed during the induction period of a chemical oxidative polymerization of aniline in dilute aqueous acids using an ammonium peroxydisulfate oxidant. Observed for the first time by static and dynamic light-scattering (LS) measurements, these aggregates are believed to be anilinium-peroxydisulfate ion clusters whose shape (spherical or rod-like) plays an important role in the overall morphology of the emeraldine salt formed (granular or fibrillar). The role of these aggregates in influencing the morphology of polyaniline is further evaluated under a variety of reaction conditions, for example, varying ionic strength, concentration, temperature, nitrogen substitution, and so forth.
Irreversibility lines and pinning force density of aligned (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ single crystals

DC magnetic properties of aligned (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ single crystals have been measured for the first time using a SQUID magnetometer in field up to 5 T and in the temperature range from 5 K to 150 K. The results confirm the existence of a broad temperature and field regime with completely reversible magnetization for these crystals. The temperature dependence of the irreversibility field H*(T) is determined from both M-H and M-T curves with fields oriented perpendicular to the ab plane of the crystal lattice. A strong field dependence of critical current density has been observed in these pristine single crystals with very weak pinning. These observations emphasize the importance of artificially introducing pinning sites in BSCCO material used for applications. Non-linear scaling models have been used to fit our experimental results to estimate the elemental pinning force density and the effective pinning potential.
From Economic Freedom to Economic and Social Poverty: Institutional Approaches to the Business Enterprise, Structural Change, and the Role for Government

The extent to which freedom should prevail continues to be a lingering question in the economic discipline. The article focuses on how freedom is conceptualized. The question addressed is whose freedoms are being served through economic self-governance. The profit seeking microeconomic objective of capitalists, as addressed by Karl Marx, must lead to structural change resulting in unemployment. But unemployment has disastrous social costs. So the promotion of freedom for capitalists comes at a high cost toward society. Thus it is argued that the concept of freedom is itself a paradox. Freedom itself must be constrained to be viable.
Imaging β-galactosidase activity using 19F chemical shift imaging of LacZ gene-reporter molecule 2 -fluoro -4-nitrophenol -β -D -galactopyranoside

Abstract 2-Fluoro-4-nitrophenol-β- d -galactopyranoside (OFPNPG) belongs to a novel class of NMR active molecules (fluoroaryl-β- d -galactopyranosides), which are highly responsive to the action of β-galactosidase (β-gal). OFPNPG has a single 19F peak (−55 ppm relative to aqueous sodium trifluoroacetate). Upon cleavage by β-gal, the pH sensitive aglycone 2-fluoro-4-nitrophenol (OFPNP) is observed at a chemical shift of −59 to −61 ppm. The chemical shift response is sufficient to observe β-gal activity using chemical shift imaging (CSI). 19F CSI studies of enzyme activity and lacZ gene expression in 9L-glioma and MCF7 breast cancer cells are presented, providing further evidence for the utility of OFPNPG as a gene-reporter molecule for future in vivo studies.
Evaluation of the Severity of Mitral Stenosis and Regurgitation

Indices have been developed that provide an improved means for evaluation of the degrees of severity of mitral stenosis and regurgitation. The severity of anatomic mitral valve disease found at surgery or autopsy was considered to be the determinant of the state of the valve. An index of the time for the diastolic atrioventricular pressure gradient to fall to half its value multiplied by 100 and divided by the cardiac index was shown to be comparable to the severity of anatomic stenosis. This index ranged from 5.7 to 10 in mitral stenosis, 0.4 to 0.8 in normal subjects, and 0.6 to 2.0 in patients with predominant mitral regurgitation. Mitral regurgitation was estimated by an index of the rate of the atrial pressure rise during ventricular systole in mm. Hg/0.02 second multiplied by 10, and divided by the cardiac index. In predominant mitral regurgitation, this index ranged from 8.0 to 15; in mitral stenosis these values were 3.7 to 6.3, and normal subjects had an index varying from 2.5 to 3.7. Both indices were significantly elevated in patients in whom stenosis and regurgitation were present at surgery. Mitral stenosis complicated by a mild degree of regurgitation gave significantly elevated stenotic indices, while the regurgitation indices were normal or slightly elevated. These indices facilitate the evaluation of either mitral stenosis or regurgitation even when both processes are present together. The significance of these indices in the evaluation of the degree of invalidism in patients with valvular disease is also discussed.
L-arginine reverses low coronary reflow and enhances postischaemic recovery of cardiac mechanical function.

Objective: To evaluate the effect of l-arginine, the physiological substrate of nitric oxide (NO), upon coronary flow (CF) and mechanical function during reperfusion following cardioplegic arrest. Methods: Two groups of isolated rat hearts were subjected to cardioplegic arrest for 4 h at 4 °C. In group 1 ( n = 10) cardioplegic arrest was followed by 4 consecutive periods of reperfusion with Krebs buffer (control), Krebs plus l-lysine (1 mmol/l), Krebs plus l-arginiae (1 mmol/l) and Krebs plus l- N Gmonomethylarginine (l-NMMA), a specific inhibitor of NO synthesis, (0.5 mmol/l). In group 2. hearts ( n = 8) were perfused by Krebs, then l-NMMA, during both pre- and postischaemic periods. In group 3, hearts ( n = 8) were perfused by Krebs, then l-arginine (1, 2 and 4 mmol/l). In group 4 ( n = 5), NO released into the perfusate was measured before ischaemia and during reperfusion. Results: In group 1, l-arginine enhanced the postischaemic CF (ml/min ± s.e.m.) from 15.0 ± 0.4 to 17.2 ± 0.4. This was reduced by l-NMMA to 11.3 ± 0.3. Postischaemic cardiac output (% of preischaemic value ± s.e.m.) was increased from 55.8 ± 2.4. to 80.1 ± 2.5 by l-arginine and dropped to 54.3 ± 2.3 with l-NMMA. In group 2, the pre- and postischaemic loss of coronary flow (CF) by l-NMMA was 51% and 31% respectively. In group 3, l-arginine did not modify CF. In group 4 the preischaemic level of NO (in nmol/ml/min) in the coronary effluent, measured by chemiluminescence, was 14.84 ± 0.83 and dropped significantly ( P < 0.05) to levels ranging from 3.80 ± 0.56 to 4.75 ± 0.51 during the postischaemic period. Conclusion: Exogenous administration of l-arginine improves low coronary reflow and postischaemic mechanical function.
Exercise effects on bone mineral density relationships to changes in fitness and fatness.

Background Weight loss typically reduces bone mineral density (BMD). Exercise may preserve or increase BMD even while reducing fatness. We examined the relationships among exercise-induced changes in fitness and fatness with BMD. Design Randomized controlled trial conducted between July 1999 and November 2003. Participants Men and women ( n =115) aged 55 to 75 years. Intervention Six months of exercise training. Main Outcome Measures Fitness measured as peak oxygen uptake and muscle strength, body composition by anthropometry, dual-energy x-ray absorptiometry, and magnetic resonance imaging. Results A total of 51 men and 53 women completed the trial. Exercise increased aerobic and strength fitness and lean body mass, and reduced general and abdominal obesity. BMD did not change among men in either group. Among women exercisers, there were reductions in total skeleton BMD ( p =0.02) and greater trochanter BMD ( p =0.02). By bivariate correlation, among women, increased femoral neck BMD was associated with increased aerobic fitness ( p =0.01) and with reduced body weight ( p =0.02) and BMI ( p =0.02). In the final regression model, 13% of the change in femoral neck BMD was explained by the change in aerobic fitness ( p p =0.04). The change in lean mass explained 20% of the change in femoral shaft BMD ( p p Conclusions When examined by group assignment, 6 months of exercise had no effect on BMD among men, and reduced BMD among women. When examined by change in fitness and fatness, women who had the greatest increases in aerobic capacity and men who had the greatest increases in strength and lean mass were more likely to increase their BMD. Exercise-induced reductions in fatness did not lead to bone loss.
Wholesalers and Caribbean Resort Hotels

Wholesale tour operators have an important role in the resorthotel industry, enabling hotels to reach potential clients in a lowcost manner. During the low season they can fill otherwise empty rooms. At the same time, hotels may run the risk of selling too many rooms at too low a price to wholesalers. During the high season hotels may displace high-paying transient guests with low-paying wholesaler guests. In areas heavily dependent on tourism, such as the Caribbean, the relationship between wholesalers and hotels is even more important because of the effect it can have on the region's economic health. This article assesses the relationship between wholesale-tour operators and Caribbean resort hotels. It includes an introduction to tourism in the Caribbean, a discussion of the structure and economics of the wholesale-tour industry, a presentation of the results of a survey of the members of the Caribbean Hotel Association, and a discussion of the implications for resort hotels and tourism.
Superconductivity in Pb inverse opal

Abstract Type-II superconducting behavior was observed in highly periodic three-dimensional lead inverse opal prepared by infiltration of melted Pb in blue (D = 160 nm), green (D = 220 nm) and red (D = 300 nm) opals and followed by the extraction of the SiO2 spheres by chemical etching. The onset of a broad phase transition (ΔT = 0.3 K) was shifted from Tc = 7.196 K for bulk Pb to Tc = 7.325 K. The upper critical field Hc2 (3150 Oe) measured from high-field hysteresis loops exceeds the critical field for bulk lead (803 Oe) fourfold. Two well resolved peaks observed in the hysteresis loops were ascribed to flux penetration into the cylindrical void space that can be found in inverse opal structure and into the periodic structure of Pb nanoparticles. The red inverse opal shows pronounced oscillations of magnetic moment in the mixed state at low temperatures, T 0.9Tc has been observed for all of the samples studied. The magnetic field periodicity of resistivity modulation is in good agreement with the lattice parameter of the inverse opal structure. We attribute the failure to observe pronounced modulation in magneto-resistive measurement to difficulties in the precision orientation of the sample along the magnetic field.
Long-term follow-up in children with functional hemispherectomy for Rasmussen's encephalitis.

Cerebral hemispherectomy has been performed for over 60 years. Multiple variations of functional hemispherectomy have been performed since its inception by Rasmussen. Long-term follow-up for these variations is lacking in the medical literature. We review the long-term follow-up for five children with Rasmussen’s encephalitis who underwent a modification of functional hemispherectomy. The length of follow-up for this cohort ranged from 13 to 23 years (mean 15.6 years). All patients experienced immediate and complete elimination of seizures. Only one patient underwent ventriculoperitoneal shunt placement. All patients are capable of ambulating on their own. Many years following their procedures, this cohort of patients remains seizure free.
Cation exchange capacity of density fractions from paired conifer/grassland soils

The cation exchange capacity (CEC) of a soil depends on the type and amount of both mineral and organic surfaces. Previous studies that have sought to determine the relative contribution of organic matter to total soil CEC have not addressed differences in soil organic matter (SOM) composition that could lead to differences in CEC. The objectives of this study were (1) to compare the CEC of two distinct SOM pools, the “light fraction (LF)” composed of particulate plant, animal, and microbial debris, and the “heavy fraction (HF)” composed of mineral-bound organic matter; and (2) to examine the effects of differences in aboveground vegetation on CEC. Soil samples were collected from four paired grassland/conifer sites within a single forested area and density fractionated. LF CEC was higher in conifer soils than in grassland soils, but there was no evidence of an effect of vegetation on CEC for the HF or bulk soil. LF CEC (but not HF CEC) correlated well with the C concentration in the fraction. The mean CEC of both fractions (per kg fraction) exceeded that of the bulk soil; thus, when the LF and HF CEC were combined mathematically by weighting values for each fraction in proportion to dry mass, the resulting value was nearly twice the measured CEC of bulk soil. On a whole soil basis, the HF contributed on average 97% of the CEC of the whole soil, although this conclusion must be tempered given the inflation of CEC values by the density fractionation procedure.
Methodology for the development of analytical fragility curves for retrofitted bridges

Fragility curves for retrofitted bridges indicate the influence of various retrofit measures on the probability of achieving specified levels of damage. This paper presents an analytical methodology for developing fragility curves for classes of retrofitted bridge systems. The approach captures the impact of retrofit on the vulnerability of multiple components, which to date has not been adequately addressed, and results in a comparison of the system fragility before and after the application of different retrofit measures. Details presented include analytical modeling, uncertainty treatment, impact of retrofit on demand models, capacity estimates, and component and system fragility curves. The findings indicate the importance of evaluating the impact of retrofit not only on the targeted response quantity and component vulnerability but also on the overall bridge fragility. As illustrated by the case study of a retrofitted multi-span continuous (MSC) concrete girder bridge class, a given retrofit measure may have a positive impact on some components, yet no impact or a negative impact on other critical components. Consideration of the fragility based only on individual retrofitted components, without regard for the system, may lead to over-estimation or under-estimation of the impact on the bridge fragility. The proposed methodology provides an opportunity to effectively compare the fragility of the MSC concrete bridge retrofit with a range of different retrofit measures. The most effective retrofit in reducing probable damage for a given intensity is a function of the damage state of interest. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation and characterization of the native iron(II)-containing DNA repair AlkB protein directly from Escherichia coli.

The Escherichia coli AlkB protein was recently found to repair cytotoxic DNA lesions 1-methyladenine and 3-methylcytosine by using a novel iron-catalyzed oxidative demethylation mechanism. This protein belongs to a family of 2-ketoglutarate−Fe(II)-dependent dioxygenase proteins that utilize iron and 2-ketoglutarate to activate dioxygen for oxidation reactions. We report here the overexpression and isolation of the native Fe(II)−AlkB with a bound cofactor, 2-ketoglutarate, directly from E. coli. UV−vis measurements showed an absorption peak at 560 nm, which is characteristic of a bidentate 2-ketoglutarate bound to an iron(II) ion. Addition of excess amounts of single-stranded DNA to this isolated Fe(II)−AlkB protein caused a 9 nm shift of the 560 nm band to a higher energy, indicating a DNA-binding-induced geometry change of the active site. X-ray absorption spectra of the active site iron(II) in AlkB suggest a five-coordinate iron(II) center in the protein itself and a centrosymmetric six-coordinate iron(...
Variation in thromboembolic complications among patients undergoing commonly performed cancer operations

Objective There is widespread evidence that cancer confers an increased risk of deep venous thrombosis (DVT). This risk is thought to vary among different cancer types. The purpose of this study is to better define the incidence of thrombotic complications among patients undergoing surgical treatment for a spectrum of prevalent cancer diagnoses in contemporary practice. Methods All patients undergoing one of 11 cancer surgical operations (breast resection, hysterectomy, prostatectomy, colectomy, gastrectomy, lung resection, hepatectomy, pancreatectomy, cystectomy, esophagectomy, and nephrectomy) were identified by Current Procedural Terminology and International Classification of Diseases, Ninth Revision codes using the American College of Surgeons National Surgical Quality Improvement Program database (2007-2009). The study endpoints were DVT, pulmonary embolism (PE), and overall postoperative venous thromboembolic events (VTE) within 1 month of the index procedure. Multivariate logistic regression was utilized to calculate adjusted odds ratios for each endpoint. Results Over the study interval, 43,808 of the selected cancer operations were performed. The incidence of DVT, PE, and total VTE within 1 month following surgery varied widely across a spectrum of cancer diagnoses, ranging from 0.19%, 0.12%, and 0.28% for breast resection to 6.1%, 2.4%, and 7.3%, respectively, for esophagectomy. Compared with breast cancer, the incidence of VTE ranged from a 1.31-fold increase in VTE associated with gastrectomy (95% confidence interval, 0.73-2.37; P = .4) to a 2.68-fold increase associated with hysterectomy (95% confidence interval, 1.43-5.01; P = .002). Multivariate logistic regression revealed that inpatient status, steroid use, advanced age (≥60 years), morbid obesity (body mass index ≥35), blood transfusion, reintubation, cardiac arrest, postoperative infectious complications, and prolonged hospitalization were independently associated with increased risk of VTE. Conclusions The incidence of VTE and thromboembolic complications associated with cancer surgery varies substantially. These findings suggest that both tumor type and resection magnitude may impact VTE risk. Accordingly, such data support diagnosis and procedural-specific guidelines for perioperative VTE prophylaxis and can be used to anticipate the risk of potentially preventable morbidity.