cssi/SciSciGPT-SciSciNet huggingface dataset:
Image‐guided radio‐frequency gain calibration for high‐field MRI

High-field (≥ 3T) MRI provides a means to increase the signal-to-noise ratio, due to its higher tissue magnetization compared with 1.5T. However, both the static magnetic field (B0) and the transmit radio-frequency (RF) field (B) inhomogeneities are comparatively higher at higher field strengths than those at 1.5T. These challenging factors at high-field strengths make it more difficult to accurately calibrate the transmit RF gain using standard RF calibration procedures. An image-based RF calibration procedure was therefore developed, in order to accurately calibrate the transmit RF gain within a specific region-of-interest (ROI). Using a turbo fast low-angle shot (TurboFLASH) pulse sequence with centric k-space reordering, a series of ‘saturation-no-recovery’ images was acquired by varying the flip angle of the preconditioning pulse. In the resulting images, the signal null occurs in regions where the flip angle of the preconditioning pulse is 90°. For a given ROI, the mean signal can be plotted as a function of the nominal flip angle, and the resulting curve can be used to quantitatively identify the signal null. This image-guided RF calibration procedure was evaluated through phantom and volunteer imaging experiments at 3T and 7T. The image-guided RF calibration results in vitro were consistent with standard B0 and B maps. The standard automated RF calibration procedure produced approximately 20% and 15–30% relative error in the transmit RF gain in the left kidney at 3T and brain at 7T, respectively. For initial application, a T2 mapping pulse sequence was applied at 7T. The T2 measurements in the thalamus at 7T were 60.6 ms and 48.2 ms using the standard and image-guided RF calibration procedures, respectively. This rapid, image-guided RF calibration procedure can be used to optimally calibrate the flip angle for a given ROI and thus minimize measurement errors for quantitative MRI and MR spectroscopy. Copyright © 2009 John Wiley & Sons, Ltd.
Ultrasound and the intestinal wall: experimental methods.

High-frequency, high-resolution ultrasound provides a new approach to imaging structures in the wall of the gastrointestinal tract. Questions about internal ultrasound include: is the ultrasound image specific for disease states, in which diseases will this technology add new and useful information not available from existing diagnostic studies, and what are the necessary characteristics for a system to accomplish these diagnoses? Answering these questions requires that precise correlations be made between the ultrasound image and pathology. We have developed a method to image a resected gastrointestinal tissue with ultrasound and to remove and examine the corresponding piece of tissue histologically. Changes in wall thickness, obliteration of layers, and changes in the characteristics of the tissue can be studied. We have shown that ultrasound can resolve the layers of the gut wall. This system should enable us to answer questions about which intestinal wall diseases are suitable for internal ultrasound ...
Correlation of activity of chlorpromazine and respective hydroxy, dimethoxy and sulphoxide analogues on dopamine, muscarinic, histamine and calmodulin sites of action

1. Chlorpromazine (CPZ) is a unique molecule which has many potential sites of action, as well as a propensity to be transformed into a host of metabolites possessing varying degrees of pharmacological and/or toxic reactions. This investigation examined the rank order of potency of CPZ and eight metabolic derivatives with respect to displacement of 3H-spiperone at central dopamine-2 (DA-2) receptors, 3H-pirenzepine at central muscarinic-1 (M-1) receptors, and inhibition of calmodulin-induced activation of cyclic AMP-dependent phosphodiesterase.2. The most potent CPZ analogues to displace labelled spiperone from DA-2 receptors in rat striatum were: 3-hydroxy-CPZ, CPZ, 3,7-dihydroxy-CPZ, and 7-hydroxy-CPZ. Intermediate potency was observed with 8-hydroxy-CPZ, 3,7,8-trihydroxy-CPZ, and 7,8-dihydroxy-CPZ. Chlorpromazine sulphoxide and 7,8-dimethoxy-CPZ displayed the least activity at DA-2 receptors.3. Displacement of labelled pirenzepine from M-1 receptors in rat frontal cortex occurred to the greatest extent...
Bargaining structure and economic performance in the open economy

Abstract It seems nowadays accepted that both centralized wage bargaining and negotiation at the firm level perform better than sectoral wage bargaining. This is because sectoral unions have enough market power to raise wages, but do not internalize all the effects of their actions. However, the ranking may be different in an open economy facing a less than infinitely elastic foreign demand, because raising wages improves the country's terms of trade, as in the optimal tariff argument. As a result, welfare is higher in the centralized setting, while sectoral bargaining is better than full decentralization when imported goods represent a large share of total consumption.
Source model for the 2001 flank eruption of Mt. Etna volcano

[1] Using interferometric synthetic aperture radar (InSAR) we constrain the deformation sources for the July–August 2001 flank eruption of Mt. Etna volcano, Italy. InSAR data from ascending and descending passes of the ERS2 satellite reveal a pattern of deformation that cannot be explained by a dike intrusion alone. In addition to a vertical dike beneath the south rift zone, the spatially large (10 km scale, 15–20 cm in range) negative range displacement lobes across the western (descending data) and eastern (ascending data) flanks require a nearly symmetric set of shallowly dipping normal faults to each side of the central dike. Complexity in the observed InSAR surface displacements constrains an additional dike intrusion beneath its NE flank. Long-term deformation of Etna's eastern and southern flanks is well established through field and InSAR observations. Therefore, the relative symmetry of motion beneath both the western and eastern flanks during the 2001 eruption is surprising. Our model of symmetric flank motion suggests that on the short time scales of a large dike intrusion volcanoes can deform differently from their long-term deformation.
Ultrafast energy transfer and population buildup among strongly coupled and curve crossing regions of the boron oxide A and X states

Abstract Boron oxide A 2 Π –X 2 Σ + chemiluminescence resulting from the reaction of boron atoms with nitrogen dioxide (NO 2 ) and ozone (O 3 ) has been studied. The reactions are characterized from 10 −5 to 10 −3 Torr and at P total ∼1 Torr in order to assess rapid X→A intramolecular vibrational-to-electronic transfers including BO ( X 2 Σ + ,v ″ =17)+ M → BO ( A 2 Π 1/2 ,v ′ =4)+ M where M=NO 2 , O 3 or a combination of these oxidants with argon, and the nature of the pressure dependent population buildup due to a possible bottleneck associated with the curve crossing of the BO X 2 Σ + and A 2 Π states between v ′ =8 and 9 A 2 Π . At the very lowest pressures, the B+NO 2 reaction also yields emission corresponding to the BO 2 A 2 Π u –X 2 Σ g + band system, however, the B–O 3 reaction results only in BO * A–X emission and produces neither BO 2 A–X nor BO B–X emission. At elevated pressures both the B–NO 2 and B–O 3 systems yield BO 2 A–X where the excited BO 2 is formed in a two-step reaction sequence. The effects of ultrafast intramolecular energy transfer, manifest at pressures as low as 2×10 −5 Torr for the B–NO 2 system, are consistent with expectations based on long-range interactions. For both the B–NO 2 and B–O 3 metatheses, the BO * A 2 Π vibrational distributions are strongly influenced by (1) a combination of population buildup in vibrational levels v ′ ⩾9 in the vicinity of the A 2 Π –X 2 Σ + curve crossing region and (2) near resonant energy transfer among nearly isoergic levels of the X 2 Σ + and A 2 Π states (both 2 Π 1/2 and 2 Π 3/2 components). The effects observed in BO demonstrate the interaction of a highly vibrationally excited ground state molecule in the presence of a collision partner with a cross-section well in excess of that expected for gas kinetic interaction and a rate constant exceeding 10 10 Torr s −1 .
Quantitative neuromuscular ultrasound in the intensive care unit

Introduction: Intensive care unit acquired weakness (ICU-AW) results from a complex mixture of nerve and muscle pathology, and early identification is challenging. This pilot study was designed to examine the ultrasonographic changes that occur in muscles during ICU hospitalization. Methods: Patients admitted to the ICU for acute respiratory failure were enrolled prospectively and underwent serial muscle ultrasound for thickness and gray-scale assessment of the tibialis anterior, rectus femoris, abductor digiti minimi, biceps, and diaphragm muscles over 14 days. Results: Sixteen participants were enrolled. The tibialis anterior (P = 0.001) and rectus femoris (P = 0.041) had significant decreases in gray-scale standard deviation when analyzed over 14 days. No muscles showed significant changes in thickness. Conclusions: Ultrasound is an informative technique for assessing muscles of patients in the ICU, and lower extremity muscles demonstrated increased homogeneity during ICU stays. This technique should be examined further for diagnosing and tracking those with ICU-AW. Muscle Nerve, 2013
Plastic microchip liquid chromatography-matrix-assisted laser desorption/ionization mass spectrometry using monolithic columns

A prototype array of monolithic liquid chromatography (LC) columns was prepared in a plastic microfluidic device for the off-line interface with matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The microfluidic channels were fabricated on a cyclic olefin copolymer (COC) plate by hot embossing. An array of methacrylate monolithic columns was prepared in the microfluidic channels by UV-initiated polymerization. The deposition system employed a pulsed electric field to transfer the effluents from multiple columns directly onto MALDI targets with a non-contact deposition method reported by Ericson et al. [C. Ericson, Q.T. Phung, D.M. Horn, E.C. Peters, J.R. Fitchett, S.B. Ficarro, A.R. Salmon, L.M. Brill, A. Brock, Anal. Chem. 75 (2003) 2309]. To characterize the off-line interface of the multiple-channel microchip LC and the MALDI-MS for the analysis of peptide mixtures, the separation efficiency and reproducibility tests in each column were carried out by separating a peptide mixture from tryptic digested proteins and depositing the multiple effluents simultaneously on the MALDI target plate. Using a MALDI-TOF mass spectrometer with a mass accuracy of +/-1 Da for peptide assignments of digested bovine serum albumin (BSA), amino acid sequence coverage of around 59% was obtained for the microchip LC-MALDI-MS compared to 23% obtained by the MALDI-MS method without LC separation. In sensitivity tests for the detection of low abundance proteins in the presence of high concentration protein mixtures, as low as 10 fmol/mul (S/N = 10) of a spiked peptide in 1 microg of digested BSA could be detected. In the analysis of a mixture of three digested proteins (BSA, myoglobin, and cytochrome c), more than twice the amino acid sequence coverage was obtained for the microchip LC-MALDI-MS compared to MALDI-MS alone.
The Pricing of Durable Exhaustible Resources: Comment

In its simplest form Hotelling's [1931] r-percent rule states that in a competitive market with no extraction costs the price of an exhaustible resource will grow at the rate of interest. For instance, if price grows at a rate slower than the rate of interest, it is in the interest of each firm to sell its entire stock immediately: The hypothesized price path is obviously not an equilibrium. Even if there are extraction costs and firms are not identical, it remains true that price net of marginal cost rises at the rate of interest. The proposition generalizes to monopolized resources: Along the equilibrium path of extraction net marginal revenue grows at the rate of interest. In a recent article in this Journal, Levhari and Pindyck [1981] (henceforth, L-P) show the r-percent rule extends to durable exhaustible resources in a competitive market. But they conclude that it does not hold in a monopoly market. This is a surprising result. Following the Hotelling logic, should it not be possible for the monopolist to rearrange production from low net marginal revenue dates to high net marginal revenue dates and raise its present value? The primary purpose of this comment is to show that Hotelling's rule does in fact hold. This is shown in Section II. Our result is compared with that of L-P in Section III. The conflict is shown to arise from a disagreement over the relevant marginal revenue. In continuous time, increasing the flow of production of a durable good at a particular point in time has no effect on the sales price at that, or any other, point in time. Hence, the rate of change in the flow of revenue at that particular point in time is the sales price: This is the definition of marginal revenue L-P use. However, durables are different from nondurables in that a perturbation in the production trajectory over some length of time will affect the entire sales price trajectory. In choosing its
Autonomy and Paternalism in Health Policy: Currents in Contemporary Bioethics

In the United States the delivery of health care traditionally has been hierarchical and strictly controlled by physicians. Physicians typically provided patients with little information about their diagnosis, prognosis, and treatment plan; patients were expected to follow their physicians’ orders and ask no questions. Beginning in the 1970s, with the widespread adoption of the doctrine of informed consent to treatment, the physician-patient relationship began to be more collaborative, although the extent of the change has been subject to debate. At a minimum, physicians began to give patients more information and asked them to consent to recommended treatment, the therapeutic privilege to withhold information from patients lost support and eventually was repudiated, and physicians embraced — at least in theory — a more patient-centered conception of health care. More recently, health care and health promotion activities have moved beyond clinical encounters and the strict confines of physician-patient interactions.
Finite permutation groups of rank 3

By the rank of a transitive permutation group we mean the number of orbits of the stabilizer of a point thus rank 2 means multiple transitivity. Interest is drawn to the simply transitive groups of "small" rank > 2 by the fact that every known finite simple group admits a representation as a primitive group of rank at most 5 while not all of these groups have doubly transitive representations. In this paper we consider finite transitive groups of rank 3, a class of groups which seems to have received little direct attention.
Evaluation of data for atmospheric models: Master Equation/RRKM calculations on the combination reaction ClO + NO2 → ClONO2, a recurring issue

Experimental data for the title reaction have been modeled using Master Equation/RRKM methods based on the Multiwell suite of programs. The starting point for the exercise was the empirical fitting provided by the NASA and IUPAC data evaluation panels, which represent the data in the experimental pressure ranges rather well. Despite the availability of quite reliable parameters for these calculations (molecular vibrational frequencies and a value of the bond dissociation energy of ClONO2, DH298(ClONO2) = 26.5 kcal mol−1, corresponding to ΔH00 = 25.35 kcal mol−1 at 0 K) and use of RRKM/Master Equation methods, fitting calculations to the reported data was anything but straightforward. Using these molecular parameters resulted in a discrepancy between the calculations and the database of rate constants of a factor of ca 4 at, or close to, the low-pressure limit. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 573–581, 2009
Control of NOD2 and Rip2‐dependent innate immune activation by GEF‐H1

Background Genetic variants of nucleotide-binding oligomerization domain 2 (NOD2) lead to aberrant microbial recognition and can cause chronic inflammatory diseases in patients with Crohn’s disease.
A phase I clinical and pharmacokinetic study of fenretinide combined with paclitaxel and cisplatin for refractory solid tumors.

Background: Fenretinide is a semi-synthetic retinoid that has pro-apoptotic effects as a single agent and synergistically with chemotherapy in vitro. We performed this study to determine the toxicity of cisplatin, paclitaxel and fenretinide in patients with advanced cancer, the recommended phase II dose of these agents together, and the pharmacokinetics (PK) of fenretinide when administered with chemotherapy.
PHOSPHORYLATION OF ΔFosB MEDIATES ITS STABILITY IN VIVO

Abstract The transcription factor, ΔFosB, accumulates in a region-specific manner in brain in response to many types of chronic stimulation due to the unusual stability of the protein. The phosphorylation of Ser27 in ΔFosB has been shown to promote this stability in vitro. We show here that this phosphorylation reaction is also important for ΔFosB's stability in the brain in vivo and for the unique behavioral plasticity mediated by this transcription factor.
Numerical solution of constrained optimal control problems with parameters

This article presents a numerical solution technique for constrained optimal control problems that contain parameters. Here, the state, control, and parameter inequality constraints are accommodated via an extended penalty function. This penalty function takes on large values when the constraints are violated and small values when the constraints are satisfied. Using the calculus of variation it is shown that the first-order necessary conditions for optimality are in the form of a two-point boundary-value problem involving differential and algebraic equations (BVP-DAE). A multiple shooting/continuation method is developed for solving this BVP-DAE. Two examples are presented to demonstrate the effectiveness of the solution approach developed in the paper.
Low-velocity impact of thin woven carbon fabric composites incorporating multi-walled carbon nanotubes

Abstract The low-velocity impact response of thin carbon woven fabric composites reinforced with functionalized multi-walled carbon nanotubes (MWCNTs) is investigated. Three loadings of MWCNTs by weight of epoxy are examined; 0.5%, 1.0%, and 1.5%. The composite plates are subjected to five levels of energy; 15, 24, 30, 60, and 120 J. The time history response of load, displacement, velocity, and energy are measured and reported. Moreover, the composite damage, associated with each energy level, is quantified and compared between different MWCNTs loadings. It is observed that the functionalized MWCNTs enhanced the impact response and limited the damage size in the woven carbon fiber composite. The addition of 1.5% MWCNTs resulted in 50% increase in energy absorption.
Factor Structure Invariance of the Kaufman Adolescent and Adult Intelligence Test Across Male and Female Samples

Multisample confirmatory factor analysis (MCFA) and latent mean structures analysis (LMS) were used to test measurement invariance and latent mean differences on the Kaufman Adolescent and Adult Intelligence Scale™ (KAIT) across males and females in the standardization sample. MCFA found that the parameters of the KAIT two-factor model were invariant across groups. A follow-up LMS found intercept differences on the Memory for Block Designs, Famous Faces, Auditory Comprehension, and Logical Steps subtests, indicating low to moderately higher expected scores for males. Thus, latent means were not tested for invariance. Although the KAIT two-factor model met partial measurement invariance, it did not demonstrate strong factorial invariance. Implications for test score interpretation are discussed.
The effects of prey relative abundance and chemical cues on prey selection in rainbow trout

An optimal foraging model was used to predict prey selection based on both energy maximization and number maximization strategies. The influence of chemical cues and relative abundance on rainbow trout diet selection was examined under laboratory conditions. In most fish, diet composition was strongly influenced by chemical cues. No fish followed an energy maximization strategy, and selection of prey based on taste persisted despite large caloric penalties associated with these choices. In the absence of chemical cues, diet composition was based on relative abundance of prey (a number maximization strategy). Within the feasible constraints of the optimal foraging model lie a large number of possible diet combinations which would provide sufficient energy for growth and reproduction. This provides a wide scope for feeding flexibility. Response to prey chemical cues may be the basis for observations of individual diet variability in trout.
Lead structures for thin film magnetic recording heads

Inductive coupling of lead structures in thin film magnetic recording heads causes crosstalk noise in multi-track or read-after-write systems. We analyze various lead structures for multi-element thin film head devices by computing mutual inductance. We find that a lead structure in which one thin film lead is placed on top of the other has superior performance with mutual coupling several orders of magnitude less for the modeled geometries. >
Cooperation without Synchronization: Practical Cooperative Relaying for Wireless Networks

Cooperative relay aims to realize the capacity of multi-antenna arrays in a distributed manner. However, the symbol-level synchronization requirement among distributed relays limits its use in practice. We propose to circumvent this barrier with a cross-layer protocol called Distributed Asynchronous Cooperation (DAC). With DAC, multiple relays can schedule concurrent transmissions with packet-level (hence coarse) synchronization. The receiver then extracts multiple versions of each relayed packet via a collision-resolution algorithm, thus realizing the diversity gain of cooperative communication. We demonstrate the feasibility of DAC by prototyping and testing it on the GNURadio/USRP software radio platform. To explore its relevance at the network level, we introduce a DAC-based medium access control (MAC) protocol, and a generic approach to integration of the DAC MAC/PHY layer into a typical routing algorithm. Considering the use of DAC for multiple network flows, we analyze the fundamental tradeoff between the improvement in diversity gain and the reduction in multiplexing opportunities. DAC is shown to improve the throughput and delay performance of lossy networks with intermediate link quality. Our analytical results have also been confirmed via network-level simulation with ns-2.
Analytic continuation of perturbative solutions of acoustic 1D wave equation by means of Padé approximants

The forward scattering series is an important and useful tool in constructing perturbative solutions to wave equation and understanding their relationship to their non-perturbative counterparts. When it converges, the series describes the total wavefield everywhere in a given medium as propagations in a reference medium and interactions with point scatterers. The method can be viewed as constructing a mapping between non-perturbative solutions of wave events and their volume point scatterer description. This mapping was shown to be required by the recently developed techniques for inverse problems based on the inverse scattering series with applications to seismic exploration (Weglein, A.B., Gasparotto, F.A., Carvalho, P.M. and Stolt, R.H., 1997, An inverse scattering series method for attenuating multiples in seismic reflection data. Geophysics, 62, 1975--1989, Weglein, A.B., Araujo, F.V., Carvalho, P.M., Stolt, R.H., Matson, K.H., Coates, R., Corrigan, D., Foster, D.J., Shaw, S.A. and Zhang, H., 2003, I...
Crown Ether Complexed Alkali Metal Picrate Ion Pairs in Water-Saturated Dichloromethane As Studied by Electrolytic Conductance and by Partitioning into Water. Effect of Lithium Chloride on Partitioning

The equilibrium constant of extraction of lithium, sodium, or potassium picrates, MPi, with 18-crown-6 or dibenzo-18-crown-6 between water and dichloromethane was determined spectrophotometrically and compared with literature values. In all instances, a 1:1:1 complex was extracted. The value of the ionic association constant of the complexed potassium picrate in the organic phase agrees well with that from electrolytic conductivity data. The latter reveals the presence of both cationic and anionic ion triplets in solutions >3 × 10-3 mol-1 dm-3. The effect of temperature on the solubility of dibenzo-18-crown-6 in water saturated with dichloromethane yields ΔH = −16.4 kJ mol-1 and ΔS = −36.02 kJ mol-1 K-1. Values of the activity coefficient of dibenzo-18-crown-6 at 298.1 K (“salting out effect”) in aqueous lithium chloride (0.10 to 0.25 mol dm-3) were estimated from the effect of the salt on the solubility, while the activity coefficient of the crown ether in dichloromethane saturated with water was evaluat...
New Bond Graph Primitive Elements for Modeling Systems Modeled by Practical Derivatives

This paper describes our work in creating and using new bond graph primitive elements to represent time-varying and/or frequency-dependent effects in engineering systems. These phenomena can be mathematically represented by fractional-order differential and integral operators. Equations with such operators arise from the analysis and application of several classes of partial differential equations [1]. Previous researchers (Bagley, Torvik, et. al.) have used this approach to further the modeling of fluid-structure interactions, heat transfer, and related control systems [3–6]. These new primitive elements represent visco-inertial and visco-elastic phenomena, whose constitutive laws are dictated by half-order derivatives and integrals. After a brief overview of the fractional derivative, we continue with a formalized mathematical development of these new primitive elements using an impedance-based approach, which provides further support in the argument for their necessity. This approach provides the system modeler with new tools to widen the range of systems that he can accurately model using a lumped-parameter bond graph approach. We illustrate the application and utility of the approach with an example problem in fluid-structure interactions by presenting bond graph models and corresponding simulations. The simulations reveal that the use of these new elements accurately captures the frequency-dependent behavior of the physical system.Copyright © 2006 by ASME
The effects of memory elaboration on adult age differences in incidental recall.

Abstract To test the hypothesis that elaboration of information declines with advancing age, young and elderly adults were tested for incidental recall of target words in base sentences, sentences for which precise (relevant) or imprecise (irrelevant) elaborations were provided, or sentences for which precise or imprecise elaborations were participant-generated. Age differences were greater when participants were instructed to generate precise elaborations than when they were provided precise elaborations, and elderly adults generated fewer precise elaborations than young adults. Results were discussed as reflecting the pervasiveness of elderly adults' difficulty in constructing effective elaborations.
Effect of simulated altitude on blood gas transport in the pigeon.

Abstract Unacclimated pigeons were exposed to various simulated altitudes. Arterial and mixed venous blood gas levels were measured. At the highest altitude 9150 m (Pb = 235 mm Hg) a remarkable degree of alkalosis was tolerated for several hours without ill effect (Pa CO 2 = 10.52 mm Hg. pHa = 7.850). This tolerance was considered an important factor in the bird's ability to survive such altitudes.
MS Xα calculations on the valence auger spectrum of CO

Abstract We have examined the utility of the MS Xα method of calculation of molecular electronic structure, in the transition-state model, as a tool in the analysis of valence Auger spectra, using CO as a test case. The method is not especially reliable in prediction of final-state energies, but serves reasonably well in prediction of the many-electron contribution to the final-state energies and in prediction of intensities.
The spinal cord, anesthesia and immobility: A re-examination

Abstract There has been much recent emphasis on the spinal cord as an important site of anesthetic action with respect to immobility. For example, decerebration or spinal cord transection in rats appears to have little effect on minimum alveolar anesthetic concentration (MAC) needed to produce immobility. Likewise, selective delivery of isoflurane, halothane or thiopental to the brain circulation necessitates increased anesthetic concentrations to provide immobility. However, we have observed that chronic spinal cord transection or acute spinal cooling results in lower MAC and reduced force of limb movement. Others have shown that discrete drug microinjections at various brain sites (gabazine in tuberomammillary nucleus or pentobarbital in the pontine tegmentum) alter anesthetic requirements or produce anesthesia. Collectively, these data suggest that, while the spinal cord is a major site of action for the immobilizing properties for anesthetics, supraspinal sites still play an important role in determining MAC.
Advancing Evidence-Based Care For Diabetes: Lessons From The Veterans Health Administration

The Veterans Health Administration (VHA) is a unique laboratory for using the electronic health record (EHR) to transform health care and accelerate discovery. This is particularly evident in the care of veterans with diabetes, who constitute a quarter of those served by the VHA. Although EHRs have enabled rapid learning, additional factors were necessary, including the lead participation of clinician-investigators, accountability through performance measurement, a delivery system focused on population health, and favorable economic externalities. “Off-the-shelf” technology is unlikely to generate similar benefits if these attributes are not in place.
Dynamic strain localization in elasto-(visco-)plastic solids, Part 2. Plane strain examples

Viscoplasticity is introduced as a procedure to regularize the elastic-plastic solid, especially for those situations in which the underlying inviscid material exhibits instabilities which preclude meaningful analysis of the initial-value problem. The procedure is general and therefore has the advantage of allowing the regularization of any inviscid elastic-plastic material. Rate dependence is shown to naturally introduce a length-scale that sets the width of the shear bands in which the deformations localize and high strain gradients prevail. Then, provided that the element size is appropriate for an adequate description of the shear band geometry, the numerical solutions are shown to be pertinent. Stable and convergent solutions with mesh refinements are obtained which are shown to be devoid of spurious mesh length-scale effects. The numerical framework adopted for this study is realistic and relevant to the solution of large scale nonlinear problems. An efficient explicit time stepping algorithm is used to advance the solution in time, and low-order finite elements with only one stress-point are used. An unconditionally stable stress-point algorithm is used to integrate the nonlinear elasto-(visco-) plastic constitutive equations. Therefore, the only numerical restriction of the proposed computational procedure stems from a time step size restriction which emanates from the explicit time integration of the equations of motion. However, since the wave speeds remain elastic, this restriction is trivially dealt with, resulting in a most efficient computational procedure.
Lessons from SADHART, ENRICHD, and other trials

Depression is highly prevalent in patients with cardiovascular disease and is independently associated with a poor prognosis when present. A very important aspect of continued therapeutic advances in this field will be the ability to show a convincing connection between the treatment of depression in patients with heart disease and a reduction in morbidity and mortality associated with the co-occurrence of these conditions. The recent SADHART (Sertraline AntiDepressant Heart Attack Trial) investigation demonstrated that sertraline is safe and efficacious in depressed patients with ischemic heart disease but was underpowered to detect a mortality difference between sertraline and placebo. The ENRICHD (ENhancing Recovery in Coronary Heart Disease) trial showed that cognitive-behavioral therapy is effective for treating depression but had no impact on cardiovascular morbidity or mortality. There are a number of methodologic complexities associated with research regarding depression and cardiovascular disease, including difficulties in the definition and measurement of depression, complexities in the conduction of large-scale trials, ethical considerations surrounding the use of placebo, and interpretation of trial results. In addition, the lack of certainty regarding the pathophysiologic link between depression and cardiovascular disease means that there is a lack of pharmacotherapy targeted specifically at the dysregulated physiology that might explain the increased morbidity and mortality seen when these two conditions occur together.
An overview of bone marrow transplantation

Abstract BMT has progressed from early isolated attempts in man through controlled animal studies in mice, rats, and dogs to the treatment of choice for some patients. 2 BMT is no longer a treatment of last resort for patients with acute leukemia; rather, it is seen as a viable alternative to conventional maintenance chemotherapy especially for patients with AML. 2 As researchers learn to apply the BMT process to partially matched and matched unrelated donors, BMT will offer treatment options to an even larger group of patients. Further research in the areas of prevention and treatment of complications and leukemic relapse will result in even better long-term survival rates. 8, 36 Research must also focus on the psychosocial costs of BMT and the quality of life experienced by long-term survivors. Nurses, as the 24-hour-a-day care providers face new challenges to provide the specialized physical, psychologic, and educational care these patients and their families require.
A solid-state intraoperative beta probe system

Successful beta-sensitive intraoperative probes must be capable of detecting relatively small amounts of beta-emitting radionuclides in an environment where a significant photon background exists. The probe system described in this investigation utilized a new photon correction scheme consisting of a stark of two ion-implanted-silicon detectors (IISDs) mounted in a compact unit. The rear detector operated as a photon monitor, whose data was used to correct for photon contamination present in the front detector's readings. The completely battery-powered system incorporated a computer-controlled data acquisition and processing system. Positron and photon detection sensitivities were measured using fluorine-18. The probe was found to have a positron detection sensitivity of 7.21/spl plusmn/0.11 cps/nCi and a 0.0001/spl plusmn/0.0389 cps/nCi photon detection sensitivity. In a simulated search for tumor remnants following a tumor resection using a phantom presenting a realistic annihilation photon background, the intraoperative probe was capable of definitively identifying 12-mm- and 6-mm-diameter, 1-mm-thick disks of simulated tumor.
The size distribution of Jupiter's main ring from Galileo imaging and spectroscopy

Abstract Galileo's Solid State Imaging experiment (SSI) obtained 36 visible wavelength images of Jupiter's ring system during the nominal mission (Ockert-Bell et al., 1999, Icarus 138, 188–213) and another 21 during the extended mission. The Near Infrared Mapping Spectrometer (NIMS) recorded an observation of Jupiter's main ring during orbit C3 at wavelengths from 0.7 to 5.2 μm; a second observation was attempted during orbit E4. We analyze the high phase angle NIMS and SSI observations to constrain the size distribution of the main ring's micron-sized dust population. This portion of the population is best constrained at high phase angles, as the light scattering behavior of small dust grains dominates at these geometries and contributions from larger ring particles are negligible. High phase angle images of the main ring obtained by the Voyager spacecraft covered phase angles between 173.8° and 176.9° (Showalter et al., 1987, Icarus 69, 458–498). Galileo images extend this range up to 178.6°. We model the Galileo phase curve and the ring spectra from the C3 NIMS ring observation as the combination of two power law distributions. Our analysis of the main ring phase curve and the NIMS spectra suggests the size distribution of the smallest ring particles is a power law with an index of 2.0±0.3 below a size of ∼15 μm that transitions to a power law with an index of 5.0±1.5 at larger sizes. This combined power law distribution, or “broken power law” distribution, yields a better fit to the NIMS data than do the power law distributions that have previously been fit to the Voyager imaging data (Showalter et al., 1987, Icarus 69, 458–498). The broken power law distribution reconciles the results of Showalter et al. (1987, Icarus 69, 458–498) and McMuldroch et al. (2000, Icarus 146, 1–11), who also analyzed the NIMS data, and can be considered as an obvious extension of a simple power law. This more complex size distribution could indicate that ring particle production rates and/or lifetimes vary with size and may relate to the physical processes that control their evolution. The significant near arm/far arm asymmetry reported elsewhere (see Showalter et al., 1987, Icarus 69, 458–498; Ockert-Bell et al., 1999, Icarus 138, 188–213) persists in the data even after the main ring is isolated in the SSI images. However, the sense of the asymmetry seen in Galileo images differs from that seen in Voyager images. We interpret this asymmetry as a broad-scale, azimuthal brightness variation. No consistent association with the magnetic field of Jupiter has been observed. It is possible that these longitudinal variations may be similar to the random brightness fluctuations observed in Saturn's F ring by Voyager (Smith et al., 1982, Science 215, 504–537) and during the 1995 ring plane crossings (Nicholson et al., 1996, Science 272, 509–515; Bosh and Rivkin, 1996, Science 272, 518–521; Poulet et al., 2000, Icarus 144, 135–148). Stochastic events may thus play a significant role in the evolution of the jovian main ring.
First-order differential-delay equation for the baroreflex predicts the 0.4-Hz blood pressure rhythm in rats.

We have described a 0.4-Hz rhythm in renal sympathetic nerve activity (SNA) that is tightly coupled to 0.4-Hz oscillations in blood pressure in the unanesthetized rat. In previous work, the relatio...
Magnesium Intake and Risk of Coronary Heart Disease among Men

Objective: Our aim in this study was to assess the relationship between magnesium intake and risk of coronary heart disease (CHD) among men.Methods: A total of 39,633 men in the Health Professionals Follow-up Study who returned a dietary questionnaire in 1986 were followed up for 12 years. Intakes of magnesium, zinc and potassium and other nutrients were assessed in 1986, 1990 and 1994. Total CHD incidence (nonfatal myocardial infarction (MI) and fatal CHD) was ascertained by biennial questionnaire and mortality surveillance confirmed by medical record review. Standard CHD risk factors were recorded biennially.Results: During 12 years of follow-up (414,285 person-years), we documented 1,449 cases of total CHD (1,021 non-fatal MI cases, and 428 fatal CHD). The age-adjusted relative risk (RR) of developing CHD in the highest quintile (median intake = 457 mg/day) compared with the lowest quintile (median intake = 269 mg/day) was 0.73 (95% CI 0.62–0.87, p for trend <0.0001). After controlling for standard CHD...
Smoking-induced vascular disease: a new twist on an old theme.

Polycyclic aromatic hydrocarbons (PAHs) are recognized widely as potential environmental procarcinogens and have attracted their share of attention from both funding agencies and scientists interested in biomedical research. Curiously, their potential relevance to cardiovascular disease, rather than cancer, has stirred less emotion. This imbalance of attention is reflected also in society’s response to that most intimate form of self-pollution with PAHs (and much else), cigarette smoking. While the States have chosen to allocate varying proportions of their Tobacco Settlements to research, cancer tends to dominate the agenda. Yet, tobacco-related cardiovascular disease yields an even more striking burden on the public health than cancer. It has been estimated that cardiovascular morbidity and mortality are increased 4-fold in smokers and by one third in passive smokers.1 One might think that such daunting figures would prompt advocacy groups, such as the American Heart Association, to lobby vigorously at the State level for an appropriate allocation of the Tobacco Settlements to cardiovascular research. Our understanding of the mechanisms by which smoking mediates cardiovascular injury and the factors that determine interindividual susceptibility to smoking-induced tissue injury is remarkably limited. In this issue of Circulation Research , Kerzee and Ramos2 draw our attention to a mechanism of potential relevance to acceleration of atherogenesis by PAHs, including those in cigarette smoke. The aryl hydrocarbon receptor (Ahr) is a member of the family of basic helix loop helix proteins (bHLHs) that contain PAS domains. This family includes proteins related to differentiation, such as MyoD, the response to hypoxia, such as Hif1α, and circadian rhythms, such as CLOCK, …
Gang Exposure and Pregnancy Incidence among Female Adolescents in San Francisco: Evidence for the Need to Integrate Reproductive Health with Violence Prevention Efforts

Among a cohort of 237 sexually active females aged 14-19 years recruited from community venues in a predominantly Latino neighborhood in San Francisco, California, the authors examined the relation between gang exposure and pregnancy incidence over 2 years of follow-up between 2001 and 2004. Using discrete-time survival analysis, they investigated whether gang membership by individuals and partners was associated with pregnancy incidence and determined whether partnership characteristics, contraceptive behaviors, and pregnancy intentions mediated the relation between gang membership and pregnancy. Pregnancy incidence was determined by urine-based testing and self-report. Latinas represented 77% of participants, with one in five born outside the United States. One quarter (27.4%) became pregnant over follow-up. Participants' gang membership had no significant effect on pregnancy incidence (hazard ratio = 1.25, 95% confidence interval: 0.54, 3.45); however, having partners who were in gangs was associated with pregnancy (hazard ratio = 1.90, 95% confidence interval: 1.09, 3.32). The male partner's perceived pregnancy intentions and having a partner in detention each mediated the effect of partner's gang membership on pregnancy risk. Increased pregnancy incidence among young women with gang-involved partners highlights the importance of integrating reproductive health prevention into programs for gang-involved youth. In addition, high pregnancy rates indicate a heightened risk for sexually transmitted infections.
LOCALE: Collaborative Localization Estimation for Sparse Mobile Sensor Networks

As the field of sensor networks matures, research in this area is focusing not only on fixed networks, but also on mobile sensor networks. For many reasons, both technical and logistical, such networks will often be very sparse for all or part of their operation, sometimes functioning more as disruption-tolerant networks (DTNs). While much work has been done on localization methods for densely populated fixed networks, most of these methods are inefficient or ineffective for sparse mobile networks, where connections can be infrequent. While some mobile networks rely on fixed location beacons or per-node, onboard GPS, these methods are not always possible due to cost, power and other constraints. In this paper we present the Low-density Collaborative Ad-Hoc Localization Estimation (LOCALE) system for sparse sensor networks. In LOCALE, each node estimates its own position, and collaboratively refines that location estimate by updating its prediction based on neighbors it encounters. Nodes also estimate (as a probability density function) the likelihood their prediction is accurate. We evaluate LOCALE'S collaborative localization both through real implementations running on sensor nodes, as well as through simulations of larger systems. We consider scenarios of varying density (down to 0.02 neighbors per communication attempt), as well as scenarios that demonstrate LOCALE'S resilience in the face of extremely-inaccurate individual nodes. Overall, our algorithms yield up to a median of 21X better accuracy for location estimation compared to existing approaches. In addition, by allowing nodes to refine location estimates collaboratively, LOCALE also reduces the need for fixed location beacons (i.e. GPS- enabled beacon towers) by as much as 64X.
CT screening for lung cancer: coping with nihilistic recommendations.

The practicing radiologist today is well persuaded that earlier diagnosis of lung cancer can be achieved with traditional-type radiography and especially with modern computed tomography. The practitioner also is confident that intervention in the context of earlier diagnosis is more effective in preventing death due to this otherwise fatal disease. The practitioner is thus inclined to consider such screening in a high-risk person with suitably long life expectancy, especially when asked to provide it. On the other hand, the practitioner is aware of official recommendations against lung cancer screening, said to be based on demonstrated lack of effectiveness of traditional radiographic screening. Some researchers have expressed concerns about screening-associated “overdiagnosis.” Given this dilemma, the critically thinking practitioner is concerned to understand the foundation of the official nihilism in evidence and reasoning, as she or he suspects that something may be seriously wrong in this. This artic...
Direct Determination of Selenium In Horse Blood By Graphite Furnace Atomic Absorption Spectroscopy

Abstract Results on a direct determination of selenium in horse blood are presented. A 10 mg/L solution of nickel was added to the blood after the blood was treated with Triton X. This provides a means of direct determination of selenium in horse blood and cuts out the time consuming digestion step. the accuracy of the method was good and the precision of greater than 10 percent was considered acceptable.
The Power of Place and the Future of Spatial Analysis in the Study of Conflict

Given the general neglect of space and place in the study of conflict and conflict processes- especially in contrast to the temporal context- this article makes a plea for a more explicit and extensive attention to the spatial contexts of social phenomena. In so doing, the paper discusses the importance of space, the relationship between space and time, how space and spatiality can be studied, and the continuing challenges that come with the study of space, and of combining the study of space and time in our analyses of social phenomena.