cssi/SciSciGPT-SciSciNet huggingface dataset:
An enhancer core element mediates stimulation of the rat beta-myosin heavy chain promoter by an alpha 1-adrenergic agonist and activated beta-protein kinase C in hypertrophy of cardiac myocytes.

Abstract In hypertrophy of cultured rat cardiac myocytes, alpha 1-adrenergic agonists activate protein kinase C (PKC) and up-regulate beta-myosin heavy chain (MHC). The 3300-base pair (bp) rat beta-MHC promoter is stimulated by both an alpha 1-agonist and a constitutively activated mutant of beta-PKC (Kariya, K., Karns, L. R., Simpson, P. C. (1991) J. Biol. Chem. 266, 10023-10026). Here, we report the convergence of alpha 1-adrenergic and beta-PKC signaling on the same element of the beta-MHC promoter. A 20-bp sequence in the beta-MHC promoter (-215/-196) was required for induction by both alpha 1-adrenergic stimulation and beta-PKC and conferred induction on a heterologous promoter. This sequence bound myocyte nuclear factor(s) through a 9-bp "enhancer core" (5'-TGTGGTATG-3'). A 3-bp mutation within the enhancer core which abolished factor binding also abolished inducibility of a 215-bp beta-MHC promoter. These results support the idea that beta-PKC is in the pathway for alpha 1-adrenergic regulation of beta-MHC transcription during cardiac myocyte hypertrophy. The enhancer core is the first PKC response element mapped by transfection of an activated PKC mutant, rather than by treatment with phorbol esters.
Development of high surface area monoliths for sulfur removal

Removal of trace sulfur compounds from fuels is important in a wide variety of applications such as transportation and stationary fuel processors for fuel cells, diesel engines, and gasoline direct injection engine NOx traps. Several materials have been found useful for sulfur removal such as nickel metal on oxidic supports, zinc-oxide adsorbents, molecular sieves, and metal-sulfur sorbents. This paper discusses structured monolith development and processing of commercially available sulfur trap materials, including methods to make various sizes of monolith substrates with honeycomb cell geometry. Challenges to develop crack-free large samples from high surface area materials will also be discussed. The physical properties of monolithic parts are compared with that of pellets.
Microstructure and Mechanisms of Ion-Simulated Irradiation-Induced Creep of Nickel

The microstructure of cold-worked, high-purity nickel has been investigated following ion-simulated irradiation-induced creep with 22-MeV deuterons and 70-MeV α-particles. The irradiations were conducted at 224°C (435°F),at stresses between 170 and 345 MPa, and at displacement rates between 13 and 30 x 10 - 8 displacements per atom per second (dpa/s). Transmission electron microscopy (TEM) procedures were used to prepare, observe, and photograph the microstructure of the ion-irradiated uniaxial creep specimens and companion unirradiated specimens. Examination of the ion-irradiated microstructure revealed no substantial differences between the deuteron and α-particle irradiated specimens. In all cases, a heterogeneous distribution of defect clusters or small dislocation loops and network dislocations, or both, were observed. A significant reduction in dislocation density from the unirradiated values was seen for the irradiated specimens. It was found that the small loops and defect clusters provided effective obstacles to dislocation motion as evidenced by the bowing of dislocations between adjacent defects. The microstructural results were evaluated in terms of the theoretical mechanisms proposed for irradiation-induced creep and the previously reported creep simulation results for nickel by Hendrick et al. A model based on the climb-controlled glide of dislocations over dispersed obstacles was found to be consistent with the microstructural results and the experimental creep data.
Landscaping the effect of CT reconstruction parameters: Robust Interstitial Pulmonary Fibrosis quantitation

Inter- and intra-rater agreement in assessing Interstitial Pulmonary Fibrosis (IPF) on CT scans is poor. Lack of approaches to understand the nuances of CT reconstruction parameters and their effect on patient scans hampers objective IPF quantification. In this paper, we propose an image analytic methodology to characterize the relationship between CT reconstruction parameters and IPF manifestation in scans. The raw data acquired from a patient was reconstructed with a combination of image thickness, interval and reconstruction kernels to derive 104 datasets. Quantitative and qualitative analyses were performed on the regional statistics computed in the neighborhood of each parenchymal voxel and for expert-chosen regions of interest (ROIs). The proposed approach could facilitate the selection of optimal CT reconstruction parameters to more robustly quantify IPF.
Micro-Raman/PL and Micro-LBIC studies of CZTSe materials and PV devices

Micro-Raman/PL/LBIC (Laser Beam Induced Current) was applied to investigate the homogeneity of polycrystalline Cu2ZnSnSe4 (CZTSe) thin-films from both front surface and cleaved edge with sub-micron spatial resolution. By comparing the materials before and after CdS coating, we have investigated the effect of non-uniformity of CdS layer on the spatial variation of the photo-response, correlating to the μ-Raman/PL probes. The CdS induced spatial variation is found to be a source of inhomogeneity in addition to that of the absorber layer itself. The devices investigated typically have > 8.5% efficiency. The contrast of the LBIC signal adjacent to the CdS rich area is found to depend on excitation laser power, indicating a potential for further efficiency improvement. Cleaved edge Raman probe has revealed possible variation in the compositions along the growth direction.
Asthma and risk of death from lung cancer: NHANES II Mortality Study.

Objective. Although smoking is the most important risk factor for lung cancer, nearly 10% of lung cancer is not attributable to smoking. Insights into risk factors for lung cancer other than smoking will become increasingly important, given decreasing trends in the prevalence of smoking. Prior research suggests asthma may increase the risk of lung cancer, particularly among nonsmokers. Methods. We used Cox regression analyses of data from a nationally representative sample of 9087 adults aged 30–75 years included in the NHANES II Mortality Study (1976–1992) to estimate the relative risk (RR) of death from lung cancer associated with self-reported asthma, independent of smoking. Results. Age-adjusted prevalence of smoking was 36.0%, and the age-adjusted prevalence of asthma was 6.1% (6.2% among nonsmokers) at baseline. During approximately 17 years of follow-up, 196 adults died of lung cancer (ICD-9 160–165). Among 6144 nonsmokers, the RR of lung cancer death comparing adults with asthma to those without w...
Investigation into the thermoelectric properties of GaSb/InAs superlattice structures

We report on our investigation into the use of III-V superlattice structures for thermoelectric (TE) applications. Preliminary review of III-V materials trends indicate that the GaSb/InAs superlattice system should offer one of the best potentials for high thermoelectric performance in the 500K-800K range. MOCVD growth of GaSb/InAs superlattice structures was carried out, and relevant structural, thermal, and electrical characterization has been performed. TEM and XRD results demonstrate a well-ordered superlattice structure. Thermal conductivity measurements reveal a reduction in the room-temperature thermal conductivity of GaSb/InAs superlattices (4.4-10.0 W/m-K), relative to either binary GaSb (32 W/m-K) or InAs (27 W/m-K). Additionally, we have worked to optimize the thermoelectric power factor (α2σ), studying both Se- and Te-doping of the superlattice structures, in an effort to demonstrate optimal thermoelectric performance. Our results demonstrate a maximum ZT of 0.36 at 400K for optimally doped n-type GaSb/InAs superlattice structures.
Combined paraesophageal hernia repair and partial longitudinal gastrectomy in obese patients with symptomatic paraesophageal hernias.

Background Obesity is a risk factor for gastroesophageal reflux disease and hiatal hernia. Studies have demonstrated poor symptom control in obese patients undergoing fundoplication. The ideal operation remains elusive. However, addressing both obesity and the anatomic abnormality should be the goal.
Fluorescent chemosensor for carbohydrates which shows large change in chelation-enhanced quenching

A new water-soluble saccharide receptor based on a naphthalic anhydride fluorophore was synthesized from 3-aminophenylboronic acid. The large change in fluorescence intensity (IIo=ca. 0.25) and measured pKa (7.7) make this compound a useful chemosensor at neutral pH.
Stable isotope models to predict geographic origin and cultivation conditions of marijuana

Abstract Here we describe stable isotope based models using hydrogen and carbon isotope ratios to predict geographic region-of-origin and growth environment for marijuana, with the intent of applying these models to analyses of marijuana trafficking in the USA. The models were developed on the basis of eradication specimens and border specimens seized throughout the USA. We tested reliability of the geographic region-of-origin and growth environment models with a “blind” set of 60 marijuana eradication specimens obtained from counties throughout the USA. The two geographic region-of-origin model predictions were 60–67% reliable and cultivation environment model predictions were 86% accurate for the blind specimens. We demonstrate here that stable isotope ratio analysis of marijuana seizures can significantly improve our understanding of marijuana distribution networks and it is for that purpose that these models were developed.
Aqueous and micelle-bound structural characterization of the epidermal growth factor receptor juxtamembrane domain containing basolateral sorting motifs.

Abstract The EGF receptor is the prototype for four highly related receptors constituting the ErbB family. The EGF receptor is normally targeted to the basolateral membrane in polarized epithelial cells, where it relays information from underlying tissues. Two basolateral sorting signals have been mapped to the cytoplasmic juxtamembrane region of the receptor, a dominant signal comprised of a polyproline core (667-PXXP) and a preceding basic residue (Arg662), and a consensus leucine-based signal (658-LL) responsible for residual sorting when the 667-PXXP signal is absent or defective. The goal of this study was to define the structure of these signals, and gain some insights into how these structures might be regulated by cellular microenvironment. Structural information was acquired for two peptides corresponding to EGF receptor residues Arg645 and Ala674 in aqueous solution or in the presence of membrane-mimicking dodecylphosphocholine micelles, using a variety of NMR and CD spectroscopic methods. Chemi...
A 5-year retrospective review of experience with Clostridium difficile-associated diarrhea.

ABSTRACTThe incidence and virulence of Clostridium difficile-associated diarrhea (CDAD) has increased dramatically from the mid 1990s to the mid 2000s. This research assessed recent CDAD patterns at a major military medical center from 2005 to 2009, by retrospectively reviewing clinical data of each CDAD case identified using the center's electronic medical record system. Two hundred and thirty-two cases were identified. There was a stable incidence rate for both inpatient (2.6–4.3/1000) and outpatient (0.02–0.04/1000) infections. Overall mortality rate was 9%. Among inpatient cases, 49% were considered to be severe, with an associated mortality of 19%. Only 12% (9/77) of severe cases were treated initially with oral vancomycin. with the majority (8/9) treated in 2009. Hospitalization was a risk factor in 71% of cases, with 29% community-acquired. Other risk factors included recent antibiotic usage (83%) and proton-pump inhibitor use (60%), with 8% having no risk factors. Most cases were initially treated...
The burden of injury in preschool children in an urban medicaid managed care organization.

Background.—Efforts to control injuries within managed care organization (MCO) populations require information about the incidence and costs associated with the injuries cared for in MCOs. Objective.—This study uses administrative data to measure the rates and the costs of burn, choking, poisoning, blunt, and penetrating injuries in an urban Medicaid MCO. Design/Methods.—A database was assembled from all medical claims submitted to a Medicaid MCO covering children aged ≤6 years in urban Baltimore between the dates of July 1, 1997, and August 7, 1999. The database included claims submitted on behalf of 1732 children observed for 2180 person-years. International Classification of Disease–9 codes were reviewed to identify claims for burn, poisoning, choking, and blunt/penetrating injuries. Trained coders reviewed outpatient records to assign E-codes. Results.—A total of 796 injuries occurred. The overall injury rate was 36.5% per year. The total cost of the medical care for these injuries was $863 552, or $396 per covered person-year, representing 42%–55% of the capitated rate received in Baltimore. Falls, being struck by something, and cutting/piercing injuries accounted for 68% of injuries. Emergency departments were the most common service sites for injured children for all injuries except in the case of burns. Conclusion.—The children enrolled in this urban Medicaid population had nearly twice the rate of injury when compared to the national average. The medical costs of injuries account for about half of the capitated reimbursement for this age group.
Fish predation in size-structured populations of treefrog tadpoles

The effects of tadpole body size, tadpole sibship, and fish body size on predation of gray treefrog tadpoles, Hyla chrysoscelis, were studied in laboratory and artificial pond experiments. Tadpole body size had a significantly positive effect on the survival of tadpoles in all experiments. The relationship between tadpole biomass eaten and biomass available suggested that fish were not satiated when consuming the largest tadpoles. Large tadpoles were probably better able to evade predators. A difference in survival among full sib families of tadpoles was only present in one family, suggesting that genetic differences in predator avoidance behavior or palatability were probably secondarily important to body size per se. Fish body size had a significantly negative effect on the survival of tadpoles. Larger fish consumed a larger number and proportion of tadpoles as well as greater biomass. These results indicate that environmental factors affecting the growth rate of tadpoles cand dramatically alter their vulnerability to gape-limited predators.
Fumigant contamination during large-scale food sampling for analysis.

Incurred fumigants were determined from twenty-two food items “before” and “after” routine large-scale preparation of samples to see if these or similar kinds of chemicals were entering the samples during the preparation. This preparation includes making the samples “table ready” before compositing them for analysis. The following five fumigant residues were determined by gas chromatography (GC): carbon disulfide (CS2), carbon tetrachloride (CCl4), chloroform (CHCl3), methyl chloroform (CH3CCl3), and tetrachloroethylene (or perchloroethylene, PCE). The number of residues determined from each sample ranged from none to four. The amounts determined varied significantly between the “before” and “after” portions from several samples. Four samples gained at least one new residue during the preparation. Six lost most of the residues determined from the original “before” portions, and 12 contained essentially the same residues before and after the preparation, although the amounts varied between the two portions. In samples where the variant residues were detected in both portions, five showed a tenfold or greater increase of CHCl3 or CCl4 and two showed a ten-fold or lesser decrease of CH3CCl3 or PCE in the “after” portions.
Neuroticism moderates the effect of maximum smoking level on lifetime panic disorder: a test using an epidemiologically defined national sample of smokers.

Abstract The present study evaluated a moderational model of neuroticism on the relation between smoking level and panic disorder using data from the National Comorbidity Survey. Participants ( n =924) included current regular smokers, as defined by a report of smoking regularly during the past month. Findings indicated that a generalized tendency to experience negative affect (neuroticism) moderated the effects of maximum smoking frequency (i.e., number of cigarettes smoked per day during the period when smoking the most) on lifetime history of panic disorder even after controlling for drug dependence, alcohol dependence, major depression, dysthymia, and gender. These effects were specific to panic disorder, as no such moderational effects were apparent for other anxiety disorders. Results are discussed in relation to refining recent panic–smoking conceptual models and elucidating different pathways to panic-related problems.
Circuit Duality and the General Network Inverse

An n-terminal electrical network is specified by a double-centered equicofactor admittance matrix, which represents the current vector as a rank n - 1 linear transformation of the voltage vector. Several dual impedance descriptions are given in terms of baseset matrices and generalized inverses. The main result is the introduction of a unique general network inverse.
CORPUS-BASED GESTURE ANALYSIS: AN EXTENSION OF THE FORM DATASET FOR THE AUTOMATIC DETECTION OF PHASES IN A GESTURE

We present the results of using an extension of the FORM gesture dataset to predict the mid-level phenomenon of phase. We compare the results of human phase prediction with automated prediction using machine-learning techniques. Specifically, we present the results of hidden Markov model experiments using an extended version of the FORM data to predict phase labels. Additionally, we compare FORM to the currently most accurate method of data gathering in this field — motion capture — by comparing the predictive accuracy of the physical gesture models produced by FORM and by motion capture for phase labeling.
Phenylalanyl puromycin formation as a model system for studying peptide bond formation.

Abstract Using polyuridylic acid as a messenger RNA, phenylalanyl-RNA may be bound to two different sites on reticulocyte ribosomes. Phenylalanyl-RNA, bound to one of these sites, can react directly to form phenylalanyl puromycin. This reaction requires the peptide synthetase. Phenylalanyl-RNA in the other site requires GTP and possibly the binding enzyme as well as the peptide synthetase to participate in this peptide bond-forming reaction. The formation of phenylalanyl puromycin may be a convenient system to study various aspects of peptide bond formation. Various parameters of this model system are described. The rate-limiting step in the formation of phenylalanyl puromycin in this system is the binding of the peptide synthetase 3 to the ribosomes. Cycloheximide inhibits peptide bond formation by inhibiting association of the peptide synthetase with ribosomes.
Primary Structure and Crystallization of Orotate Phosphoribosyltransferase from Salmonella typhimurium

Orotate phosphoribosyltransferase (OPRTase; EC 2.4.2.10) catalyzes phosphoribosyl group transfer between alpha-d-5-phosphoribosyl-1-pyrophosphate and orotate to form orotidine-5′-monophosphate and pyrophosphate, the nucleotide-forming step in pyrimidine biosynthesis. It is one of ten PRTases that perform viral roles in de novo and salvage pathways for purine, pyrimidine and pyridine nucleotides. Although the PRTases are important drug targets, they are poorly understood mechanistically, and no three-dimensional structures exist. Here, we report the complete sequence of the Salmonella typhimurium pyrE gene and the deduced sequence of the OPRTase gene product. OPRTase forms tetragonal crystals from polyethylene glycol solutions; these crystals diffract to better than 2 A resolution, and are stable to radiation damage. The space group is P41212 (or P43212) with unit cell dimensions of a = b = 48·5 A, c = 210·5 A, and α = β = γ = 90°. A crystalline form of the selenomethionine derivative of the protein is also reported.
Enhancing structural support of the dermal microenvironment activates fibroblasts, endothelial cells, and keratinocytes in aged human skin in vivo.

The dermal extracellular matrix (ECM) provides strength and resiliency to skin. The ECM consists mostly of type I collagen fibrils, which are produced by fibroblasts. Binding of fibroblasts to collagen fibrils generates mechanical forces, which regulate cellular morphology and function. With aging, collagen fragmentation reduces fibroblast–ECM binding and mechanical forces, resulting in fibroblast shrinkage and reduced function, including collagen production. Here, we report that these age-related alterations are largely reversed by enhancing the structural support of the ECM. Injection of dermal filler, cross-linked hyaluronic acid, into the skin of individuals over 70 years of age stimulates fibroblasts to produce type I collagen. This stimulation is associated with localized increase in mechanical forces, indicated by fibroblast elongation/spreading, and mediated by upregulation of type II TGF-β receptor and connective tissue growth factor. Interestingly, enhanced mechanical support of the ECM also stimulates fibroblast proliferation, expands vasculature, and increases epidermal thickness. Consistent with our observations in human skin, injection of filler into dermal equivalent cultures causes elongation of fibroblasts, coupled with type I collagen synthesis, which is dependent on the TGF-β signaling pathway. Thus, fibroblasts in aged human skin retain their capacity for functional activation, which is restored by enhancing structural support of the ECM.
Spiral Servo Writing in Hard Disk Drives Using Iterative Learning Based Tracking Control

Abstract The servo control in a hard disk drive (HDD) system relies heavily on the position information obtained from the servo sectors. As the tracks-per-inch (TPI) gets higher and higher in HDDs, writing of servo sectors takes a longer and longer time. One way to solve this problem is to use servo track writers to write spiral servo patterns on the disks and then perform self servo writing (SSW) within each HDD unit. The quality of the spirals is the key to achieve high TPI in SSW. This paper discusses high precision tracking control algorithms for the writing of spiral servo patterns. An iterative learning scheme is introduced, which combines a disturbance observer with the zero phase error tracking algorithm, and develops a new way of designing asymptotically optimal feedforward inputs for a general two degree of freedom control systems. In learning control schemes, non-repetitive disturbances have an adverse influence on the tracking performance. The paper analyzes this situation, and develops a robust learning scheme to deal with the problem.
Targeting cardiac potassium channels for state-of-the-art drug discovery

Introduction: Cardiac K+ channels play a critical role in maintaining the normal electrical activity of the heart by setting the cell resting membrane potential and by determining the shape and duration of the action potential. Drugs that block the rapid (IKr) and slow (IKs) components of the delayed rectifier K+ current have been widely used as class III antiarrhythmic agents. In addition, drugs that selectively target the ultra-rapid delayed rectifier current (IKur) and the acetylcholine-gated inward rectifier current (IKAch) have shown efficacy in the treatment of patients with atrial fibrillation. In order to meet the future demand for new antiarrhythmic agents, novel approaches for cardiac K+ channel drug discovery will need to be developed. Further, K+ channel screening assays utilizing primary and stem cell-derived cardiomyocytes will be essential for evaluating the cardiotoxicity of potential drug candidates.Areas covered: In this review, the author provides a brief background on the structure, fu...
Ladder-Related Injuries Treated in Emergency Departments in the United States, 1990–2005

BACKGROUND: Ladder use is involved in many occupational and non-occupational activities. Falls from ladders can result in serious injury and affect people of all ages. The purpose of this study was to comprehensively examine nonfatal ladder-related injuries on a national level. METHODS: Using the National Electronic Injury Surveillance System (NEISS) database, cases of nonfatal ladder-related injuries treated in U.S. emergency departments (EDs) from 1990 through 2005 were selected using NEISS ladder product codes. Analysis was conducted from June 2006 to August 2006. RESULTS: An estimated 2,177,888 (95% confidence interval [CI]=1,885,311-2,470,466) individuals ranging in age from 1 month to 101 years were treated in U.S. EDs for ladder-related injuries during the 16-year study period, yielding an average of 136,118 cases annually, an average of 49.5 per 100,000 people. Males predominated in ladder-related injuries (76.5%, 95% CI=75.8-77.2). Fractures were the most common type of injury (31.5%, 95% CI=30.5-32.6). The body parts most frequently injured were the legs and feet (30.4%, 95% CI=29.5-31.2). Nearly 10% of injuries resulted in hospitalization (8.5%, 95% CI=7.4-9.6) or transfer to another hospital (1.4%, 95% CI=1.1-1.8), approximately twice that of consumer product-related injuries overall. The number of ladder-related injuries increased by more than 50% from 1990 to 2005. Ladder-related injuries per 100,000 people rose almost 27% during the 16-year study period. Of the cases for which locale of injury was recorded, 97.3% occurred in non-occupational settings, such as homes and farms. CONCLUSIONS: Given the 50% increase in ladder-related injuries during the study period, the relatively high likelihood of hospital admission, and the predominance of injuries in non-occupational settings, increased efforts are needed to prevent ladder-related injuries. Language: en
NUTRITIONAL INTERVENTIONS AND THERAPIES IN AUTISM A SPECTRUM OF WHAT WE KNOW: PART 2

Part 1 in this series (“Nutritional Intake and Therapies in Autism”) addressed the nutrient intake of children with autism and the myriad factors likely to affect dietary intake and nutritional sta...
NOISE FROM SUPERSONIC COAXIAL JETS, PART 3: INVERTED VELOCITY PROFILE

Abstract The instability wave noise generation model is used to study the instability waves in the two shear layers of an inverted velocity profile, supersonic, coaxial jet and the noise radiated from the dominant wave. The inverted velocity profile jet has a high speed outer stream surrounding a low speed inner stream and the outer shear layer is always larger than the inner shear layer. The jet mean flows are calculated numerically. The operating conditions are chosen to exemplify the effect of the coaxial jet outer shear layer initial spreading rates. Calculations are made for the stability characteristics in the coaxial jet shear layers and the noise radiated from the instability waves for different operating conditions with the same total thrust, mass flow and exit area as a single reference jet. Results for inverted velocity profile jets indicate that relative maximum instability wave amplitudes and far field peak noise levels can be reduced from that of the reference jet by having higher spreading rates for the outer shear layer, low velocity ratios and outer streams hotter than the inner stream.
Workshop on health search and discovery: helping users and advancing medicine

This workshop brings together researchers and practitioners from industry and academia to discuss search and discovery in the medi-cal domain. The event focuses on ways to make medical and health information more accessible to laypeople (including enhancements to ranking algorithms and search interfaces), and how we can dis-cover new medical facts and phenomena from information sought online, as evidenced in query streams and other sources such as social media. This domain also offers many opportunities for appli-cations that monitor and improve quality of life of those affected by medical conditions, by providing tools to support their health-related information behavior.
Effect of nifedipine on the myocardial and vascular response to myocardial ischemia

Nifedipine reduces reactive hyperemia following brief coronary artery occlusions. To determine whether this is related to improvement in collateral blood flow to ischemic myocardium or alterations in myocardial oxygen consumption, ten chloralose anesthetized dogs were instrumented with coronary sinus catheters, circumflex artery flowmeters, and ultrasonic microcrystals for measurement of myocardial segment shortening. Myocardial oxygen consumption and circumflex coronary artery flow were determined at rest and during incremental infusions of isoproterenol. Myocardial blood flow measured with microspheres and segmental function were assessed during and following 30- and 60-second coronary artery occlusions. Thirty minutes after the intravenous administration of nifedipine, 10 μg/kg iv, all measurements were repeated. Nifedipine did not alter myocardial oxygen consumption or the relationship between oxygen consumption and circumflex coronary artery flow either at rest or during isoproterenol infusion. Following 60-second coronary occlusions, nifedipine reduced peak circumflex coronary artery flow (176±99 vs. 128±68 cc/min) and reactive hyperemia debt repayment (221±84 vs. 158±66%; p<0.01). Nifedipine did not alter flow to ischemic segments during coronary artery occlusions (0.16±0.10 vs. 0.19±0.13 ml/min/g mean transmural flow). Furthermore, nifedipine did not affect the severity of ischemic segment dysfunction, nor the rate of recovery of ischemic segment function following release of coronary artery occlusion. We conclude that the reduction in reactive hyperemia induced by nifedipine was not related to alterations in the severity of hypoperfusion in ischemic areas, or alterations in myocardial oxygen consumption. Reductions in reactive hyperemia produced by nifedipine did not impair recovery of mechanical function in postischemic myocardium.
Expected versus observed error in a computer-aided navigation system for spine surgery

Abstract Error analysis of surgical navigation is extremely important in systems intended for clinical use. Knowledge of the overall clinical accuracy is vital for physicians during the preoperative planning process. Recent results in error analysis give us an idea of the expected impact of fiducial placement on overall clinical error (IEEE Trans. Med. Imaging 17 (1998)). We discuss this impact with respect to an end-to-end system for image-guided spine surgery. We show that fiducial placements have a definite effect on the clinical accuracy of our spine surgery system. Our results agree with the prediction that areas outside of the “bounding box” of fiducials are subject to greater clinical error.
Expression of DNA transferred into mammalian cells

There are several methods to introduce purified DNA into mammalian cells. These include microinjection into the nuclei of the recipient cells and complexing the DNA with facilitating agents such as calcium-phosphate. After it enters the nucleus, the DNA is expressed in a large proportion of the cells. This expression is dependent upon cis-acting sequences that are recognized by the mammalian transcriptional and translational machinery. In a smaller proportion of cells, the exogenous DNA becomes covalently integrated into the host cell DNA at random sites. Non-selectable genes can be introduced into mammalian cells by ligating them to a selectable marker or mixing the DNA with carrier DNA containing a selectable marker. The DNA that is introduced into mammalian cells can be rescued for examination and analysis. These gene transfer methods have already proven to be useful in identification of sequences which are necessary for normal gene expression as well as gene regulation. In addition a number of genes have been isolated using gene transfer methods. DNA mediated gene transfer holds much promise to target genes to specific sites in the chromosomes, to understand mechanisms of mammalian development and cell differentiation and is expected to provide a method to produce important and novel gene products that may be used for diagnostic and therapeutic purposes.
Modification of the characteristics of dopamine transporter in brain regions and spinal cord of morphine tolerant and abstinent rats

The specific binding of [3H]GBR 12935 to crude synaptosomal membranes of brain regions and spinal cord of morphine tolerant and abstinent rats was investigated. Male Sprague-Dawley rats were implanted with 6 morphine pellets each containing 75 mg of morphine base during a 7-day period. Placebo pellet implanted rats served as controls. Rats sacrificed without removal of the pellet were considered tolerant whereas those from which pellets were removed 16 hr prior to sacrificing were labeled abstinent. The binding of [3H]GBR 12935 was initially determined at a 1 nM concentration in all brain regions and spinal cord, which was followed by the determination of Bmax and Kd values in the corpus striatum, a highly enriched region for the dopamine transporter. In morphine tolerant rats, the binding of [3H]GBR 12935 was increased in the hypothalamus (182%) but was decreased in the corpus striatum (34%) and spinal cord (30%). The decrease in binding in the corpus striatum was due to an increase in the Kd value of [3H]GBR 12935. However, during morphine withdrawal, the binding of [3H]GBR 12935 was still higher in the hypothalamus (255%) but was decreased in the hippocampus (53%). Thus, chronic administration of morphine results in changes in the dopamine transporter function in selected brain regions and the spinal cord, and these changes are dependent upon whether or not the animals are undergoing the abstinence syndrome.
Evaluating the value of a web-based natural medicine clinical decision tool at an academic medical center

Background Consumer use of herbal and natural products (H/NP) is increasing, yet physicians are often unprepared to provide guidance due to lack of educational training. This knowledge deficit may place consumers at risk of clinical complications. We wished to evaluate the impact that a natural medicine clinical decision tool has on faculty attitudes, practice experiences, and needs with respect to H/NP.
Solution structure of a luteoviral P1-P2 frameshifting mRNA pseudoknot

A hairpin-type messenger RNA pseudoknot from pea enation mosaic virus RNA1 (PEMV-1) regulates the efficiency of programmed -1 ribosomal frameshifting. The solution structure and 15N relaxation rates reveal that the PEMV-1 pseudoknot is a compact-folded structure composed almost entirely of RNA triple helix. A three nucleotide reverse turn in loop 1 positions a protonated cytidine, C(10), in the correct orientation to form an A((n-1)).C(+).G-C(n) major groove base quadruple, like that found in the beet western yellows virus pseudoknot and the hepatitis delta virus ribozyme, despite distinct structural contexts. A novel loop 2-loop 1 A.U Hoogsteen base-pair stacks on the C(10)(+).G(28) base-pair of the A(12).C(10)(+).G(28)-C(13) quadruple and forms a wedge between the pseudoknot stems stabilizing a bent and over-rotated global conformation. Substitution of key nucleotides that stabilize the unique conformation of the PEMV-1 pseudoknot greatly reduces ribosomal frameshifting efficacy.
Evolutionary Algorithm for the Placement of Fluid Power Valves

Placement and routing of fluid power valves impact operational or manufacturing costs. Choosing the right placement that provides optimum routing configuration, and subsequently determining the optimum routing for a given placement, are both hard problems. Evolutionary algorithms, for two categories, are developed here to determine the placement of the valves, based on the optimal routing configuration that minimizes costs. The two categories we consider are a) the placement of conventional valves on a valve-stand and b) the placement of cartridge valves on a manifold block. Our results meet or exceed experienced designers’ solutions.Copyright © 2002 by ASME
Theoretical determinants of condom use intentions for vaginal sex with a regular partner among male and female injecting drug users

The factors influencing 90 male and 42 female injecting drug users' (N = 132) intentions to always use a condom while having vaginal sex with a regular partner were analyzed. For male IDUs, the partner norm (beta = 0.40), the mean of the weighted control beliefs (beta = 0.26), attitude (beta = 0.22) and perceived behavioural control (beta = 0.15) were important predictors of intention (R = 0.81). In contrast, for female IDUs, only the partner norm emerged as an independent predictor of intention (R = 0.72). Thus interventions directed at female IDUs will be most effective if they change the women's beliefs that 'my regular partner thinks we should always use condoms for vaginal sex'. For male IDUs, two behavioural beliefs and two control beliefs were identified as critical targets for an intervention: the behavioural beliefs that consistent condom use would make me feel more relaxed and cleaner, and the control beliefs concerning the regular partner's openness to condom use and the likelihood that she wou...
The relative detection efficiency calibration of a Ge(Li) detector at low energies

Abstract The relative detection efficiency of gamma-ray full energy peaks in the energy region 20–100 keV was determined using a modified pair-point method. An overall accuracy of 15% was obtained in this energy region.
The Economics of Influence

The economics profession has fallen into the habit of telling a limited "economics of control" policy story in their teaching of economics. While it is a useful story, it leaves out important elements of policy. This paper briefly analyzes the history of the profession's current policy story, and argues that a newly developed complexity theory offers a richer policy narrative. It is a policy story in which the government and market coevolve, and the role of government policy is to positively influence that evolution, not to control the system. The paper concludes with a discussion of some implications that the acceptance of an economics-of-influence approach to policy would have for the story economists tell about policy.
Fire analysis in the eighteenth century: Herman Boerhaave and scepticism about the elements.

AbstractIn the eighteenth century, many chemists asserted that chemical operations could not decompose a substance into its natural, constituent elements or principles. One such chemist was Herman Boerhaave (1668–1738), who claimed, following the work of Robert Boyle and Joan Baptista van Helmont, that examples of these alleged analyses were, in fact, not reductions of a body into elements, but rather the rearrangement of its particles by the fire. Since we cannot observe the shape and arrangement of particles directly, he reasoned, any claim regarding the elemental status of a substance was purely speculative and inadmissible in his chemistry. As a result, Boerhaave devised a system of chemistry which, in effect, accepted no elemental substances and which focused on understanding how the chemist's ‘instruments,’ including fire and chemical menstrua, effected changes in matter. I conclude by showing how Boerhaave's conclusion had ramifications for later developments in chemistry, especially those of the F...
BASAR: a framework for integrating agents in the World Wide Web

At GMD's Human Computer Interaction Research Division, we are working on a system called BASAR (Building Agents Supporting Adaptive Retrieval). BASAR, a Smalltalk-based program that runs on Unix platforms, involves intelligent agents that actively support construction and management of a user's personal information space. Possible agent tasks include supporting navigation and browsing; simplifying information retrieval; sorting, organizing, and indexing user-jobs; and filtering information from large databases. BASAR's interface is based on the concept of indirect management. That is, computer agents support human users in a cooperative process where both agents and users can initiate communication, monitor events, and perform tasks. >
X-gtrbac admin: A decentralized administration model for enterprise-wide access control

The modern enterprise spans several functional units or administrative domains with diverse authorization requirements. Access control policies in an enterprise environment typically express these requirements as authorization constraints. While desirable for access control, constraints can lead to conflicts in the overall policy in a multidomain environment. The administration problem for enterprise-wide access control, therefore, not only includes authorization management for users and resources within a single domain but also conflict resolution among heterogeneous access control policies of multiple domains to allow secure interoperation within the enterprise. This work presents design and implementation of X-GTRBAC Admin, an administration model that aims at enabling administration of role-based access control (RBAC) policies in the presence of constraints with support for conflict resolution in a multidomain environment. A key feature of the model is that it allows decentralization of policy administration tasks through the abstraction of administrative domains, which not only simplifies authorization management, but is also fundamental to the concept of decentralized conflict resolution presented. The paper also illustrates the applicability of the outlined administrative concepts in a realistic enterprise environment using an implementation prototype that facilitates policy administration in large enterprises.
Rates of Electron-Transfer Across Liquid/Liquid Interfaces. Effects of Changes in Driving Force and Reaction Reversibility†

Rates of electron-transfer between redox reactants located on opposite sides of the interface between thin layers of organic solvents on graphite electrode and aqueous solutions were measured by means of steady-state electrochemistry. Changes in the overall driving forces for irreversible reactions produced changes in rate that fit no simple behavioral pattern. For reversible reactions, a regular increase in rate with driving force was obtained. Evidence for a significant effect of diffuse-layer potentials on reaction rates was not found.
On the linearity of iron dichloride

Reexamen de donnees de diffraction electronique et nouveaux calculs des proprietes vibrationnelles de FeCl 2 : la molecule serait lineaire a l'etat gazeux
A New Species of the Chydorus sphaericus Group (Cladocera, Chydoridae) from Western Montana

Chydorus biovatus differs from C. sphaericus sens. str. in that the ephippial female carries two resting eggs, for which the brood pouch is expanded dorsally. resulting in a sharp angle in lateral contour near the junction of the head and shell and in the postpore distance being much elongated. The mature male has the pre-anal angle of the postabdomen rounded and the rostrum broadly rounded, both features being much different than in C. sphaericus sens. str. In North America there is a progressive replacement of C. brevilabris-group species in the South to C. sphaericus-group species in the Far North. Production of two resting eggs by Chydorus piger is recorded.
Long-term treatment results of postoperative radiation therapy for advanced stage oropharyngeal carcinoma.

Background. The authors report the long-term treatment results for advanced stage base of tongue (BOT) and tonsillar fossa (TF) carcinomas treated with surgery and postoperative radiation therapy (RT) at Memorial Sloan-Kettering Cancer Center. Methods. Between 1973 and 1986, 51 patients with squamous cell carcinoma of the BOT (n = 31 patients) and TF (n = 20 patients) were treated with surgery plus RT. Indication(s) for RT included: advanced disease (Stage T3/T4, 34 patients [66%]); close or positive margins (33 patients, 64%) and multiple positive neck nodes (43 patients, 84%). Results. The 7-year actuarial local control rates for BOT and TF lesions were 81% and 83%, respectively. Local control was achieved in 17 of 18 (94%) patients with T3 lesions, and 12 of 16 (75%) patients with T4 lesions. Among patients with positive or close margins who received postoperative doses of 60 Gy or more, the long-term control rate was 93%. The presence of a treatment interruption had a negative effect on the local control rates. The actuarial control among patients who required a treatment break was 64%; for those not requiring interruption of their treatment, the actuarial control was 93% (P = 0.05). At 7 years, the overall survival for all patients was 52y0, and the disease-free survival was 64%. The actuarial incidence of neck failure was 21% and 18% for BOT and TF, respectively. The likelihood of having distant metastasis at 7 years for all patients was 30%. The actuarial incidence of having a second malignancy was 35% for patients with BOT disease. Second malignancy was not observed among patients with TF lesions. Conclusions. The authors conclude that surgery and postoperative RT can provide excellent long-term, disease-control rates for patients with advanced BOT and TF tumors. However, current strategies for BOT lesions have been directed at tongue preservation without surgery.
Enamel matrix derivative improves clinical outcomes in intrabony periodontal defects

Abstract Original Article Kalpidis CDR, Ruben MP. Treatment of intrabony periodontal defects with enamel matrix derivative: a literature review. J Periodontol 2002;73:1360–76. Level of Evidence 4 Purpose To examine the short-term (ie, 6–12 months) clinical outcomes associated with use of enamel matrix derivative in the treatment of intrabony periodontal defects utilizing a meta-analysis approach Source of Funding Not reported Type of Study/Design Randomized Controlled Trials
NMR Solution Structure, Stability, and Interaction of the Recombinant Bovine Fibrinogen alphaC-Domain Fragment

According to the current hypothesis, in fibrinogen, the COOH-terminal portions of two Aα chains are folded into compact αC-domains that interact intramolecularly with each other and with the central region of the molecule; in fibrin, the αC-domains switch to an intermolecular interaction resulting in αC polymers. In agreement, our recent NMR study identified within the bovine fibrinogen Aα374-538 αC-domain fragment an ordered compact structure including a β-hairpin restricted at the base by a 423–453 disulfide linkage. To establish the complete structure of the αC-domain and to further test the hypothesis, we expressed a shorter αC-fragment, Aα406-483, and performed detailed analysis of its structure, stability, and interactions. NMR experiments on the Aα406-483 fragment identified a second loose β-hairpin formed by residues 459–476, yielding a structure consisting of an intrinsically unstable mixed parallel/anti-parallel β-sheet. Size-exclusion chromatography and sedimentation velocity experiments revealed that the Aα406-483 fragment forms soluble oligomers whose fraction increases with increasing concentration. This was confirmed by sedimentation equilibrium analysis, which also revealed that the addition of each monomer to an assembling αC oligomer substantially increases its stabilizing free energy. In agreement, unfolding experiments monitored by CD established that oligomerization of Aα406-483 results in increased thermal stability. Altogether, these experiments establish the complete NMR solution structure of the Aα406-483 αC-domain fragment, provide direct evidence for the intra- and intermolecular interactions between the αC-domains, and confirm that these interactions are thermodynamically driven.