cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of Habitat Alteration on the Epizootiology of Myxobolus cerebralis, the Causative Agent of Salmonid Whirling Disease

Abstract: Whirling disease, caused by the myxozoan parasite Myxobolus cerebralis, is a serious health threat to salmonid fish and its control remains problematic. The parasite has a 2-host life cycle involving a salmonid and the aquatic oligochaete Tubifex tubifex. A commonly used strategy to control parasites that requires an obligatory invertebrate host is to eliminate or reduce the host population size to a point where parasite transmission can no longer occur. Large numbers of T. tubifex are frequently found in degraded habitats that are characterized by an abundance of fine sediments, organic matter, and a lack of aquatic invertebrate diversity. If such environments are rehabilitated, then the normal flora and fauna should re-establish and the numbers of T. tubifex should decline due to their inability to compete with the re-established invertebrates. During an epizootiological study on Rock Creek, located in west-central Montana, 2 opportunities were available to examine the effects of habitat rest...
Smart Growth and the Greening of Comprehensive Plans and Land Use Regulations

Global warming, climate change, reducing greenhouse gas emissions, reducing the carbon footprint, and going green are just some of the buzz words in the news over the last two years that have captured the attention of lawmakers and policymakers at all levels of government. In Congress, lawmakers have proposed, among other things, mandating standards to reduce greenhouse gas emissions, and governors across the country have announced myriad programs designed to encourage the use by governments of green products, the construction of green buildings, and the offering of a combination of tax incentives and grants for private developers and other members of the public who develop and install various renewable energy products. However, It is initiatives at the local government level that have the greatest potential for most quickly and most efficiently slowing the pace of global warming. This is because local governments are the critical decision-makers in how communities use and conserve key resources. Municipalities serious about curbing emissions as well as energy and water usage within their communities, to both combat global warming and to preserve the immediate environment, have found many successful ways to implement plans that reduce the strain on environmental resources. Local governments have begun to incorporate principles and goals of sustainability and carbon reduction into comprehensive land use plans. This paper begins to examine the elements of a "green audit" for local comprehensive plans and land use regulations.
ASSESSING THE FALSIFIABILITY OF EXTREME LINKING

Extreme linkings are performed in settings in which neither equivalent groups nor anchor material is available to link scores on two assessments. Examples of extreme linkages include links between scores on tests administered in different languages or between scores on tests administered across disability groups. The strength of interpretation attached to a linkage depends on the proper design and execution of a sound data collection plan. The current paper uses a real data set to illustrate how to indirectly assess the quality of linking the scores on two assessments that contain neither equivalent groups nor common anchor material.
Origin of Norepinephrine in the Heart

NOREPINEPHRINE is present in various organs of the body and in the blood plasma1. The adrenal medulla is not necessary for the maintenance of tissue stores of this catecholamine1, and it is likely that synthesis of norepinephrine occurs in the sympathetic nervous tissue throughout the body. Norepinephrine in the plasma originates from discharge of the neurohumour from the sympathetic nerve endings. The circulating catecholamine is excreted, metabolically inactivated (predominantly by O-methylation), or rebound in the tissues2,3. A portion of the norepinephrine present in each organ is derived from the circulating pool of catecholamine. The ability of the heart to take up, concentrate, and store intravenously administered norepinephrine has been amply demonstrated4–6. It has recently been shown that the isolated perfused heart is capable of synthesis of norepinephrine from tyrosine, at a sufficiently rapid rate to account for a considerable portion of the norepinephrine in this organ7. Thus norepinephrine stores in the heart could be maintained in part by extraction of the catecholamine from the circulation and in part by synthesis. We have used an isotope dilution technique to demonstrate that in the normal rat about 60 per cent of the norepinephrine present in the heart is synthesized in this organ, while the remainder is derived from the circulating pool of norepinephrine
The physical chemistry of the precipitation stripping process for removing iron (III) from carboxylate solutions with dilute Sulphuric Acid

Abstract Precipitation stripping is a single-stage process for stripping a metal from a loaded liquid cation exchanger with dilute mineral acid while simultaneously precipitating a hydrolyzed phase. The process has potential applications for removing iron from hydrometallurgical process streams; iron (III) can be stripped from carboxylate solutions with dilute H 2 SO 4 (10–40 g/l), at 100°C under atmospheric pressure, to give goethite or basic sulphates. Experimental results for precipitation stripping are summarized. The thermodynamics of the process are examined and equilibrium constants for the precipitation stripping process are estimated at 25°C and 100°C. For the formation of goethite and hematite, these constants are very high at both temperatures. This indicates that iron (III) can only be extracted in reasonable concentrations by carboxylic acids before precipitates have nucleated, or when the metastable phase Fe (OH) 3 is present. The sluggish kinetics of Fe(III) hydrolysis and precipitation favour extraction at 25°C. At 100°C, however, goethite and hematite precipitate more rapidly, which drives the precipitation stripping process to near completion. The structure of the iron carboxylate complexes within the organic phase is discussed, along with the influence of these structures on the kinetics of stripping and the nature of the hydrolysis products.
Spectral Convergence of Quasi-One-Dimensional Spaces

We consider a family of non-compact manifolds Xe (“graph-like manifolds”) approaching a metric graph X0 and establish convergence results of the related natural operators, namely the (Neumann) Laplacian $$\Delta _{X_{\epsilon}}$$ and the generalized Neumann (Kirchhoff) Laplacian $$\Delta _{X_0 } $$ on the metric graph. In particular, we show the norm convergence of the resolvents, spectral projections and eigenfunctions. As a consequence, the essential and the discrete spectrum converge as well. Neither the manifolds nor the metric graph need to be compact, we only need some natural uniformity assumptions. We provide examples of manifolds having spectral gaps in the essential spectrum, discrete eigenvalues in the gaps or even manifolds approaching a fractal spectrum. The convergence results will be given in a completely abstract setting dealing with operators acting in different spaces, applicable also in other geometric situations.
Social positions in influence networks

In this article we derive implications about social positions from a formal theory of social influence. The formal theory describes how, in a group of actors with heterogeneous initial opinions, a network of interpersonal influences enters into the formation of actors' settled opinions. We derive the following conclusions about a special form of structural equivalence. If actors are structurally equivalent in the network of interpersonal influences, then any dissimilarity of their initial opinions is reduced by the social influence process. If the social positions of actors are identical, i.e. if they have identical initial opinions and are structurally equivalent in the influence network, then they have identical opinions at equilibrium. If actors are not structurally equivalent in the network of interpersonal influences, then the social influence process does not necessarily reduce dissimilarities of initial opinions. We extend our analysis to consider automorphic equivalence.
Atmospheric Transmission from a 4-pi Light Source to a 2-pi Receiver.

This survey report points out the progress and insufficiencies in the assessment and prediction of atmospheric effects on thermal radiation from an effective point source in the troposphere to a 2-π sr receiver at the ground. Major findings of investigators during the past two decades are summarized, which also provide additional conclusions. Complicated transmission problems can, futhermore, be treated theoretically by assuming model type atmospheres and solving the radiation transfer equation by an available technique such as the Monte Carlo method. Some of the major results of this method are also presented.
The polarography of aqueous pertechnetate ion

The polarographic reduction of pertechnetate in 4-0.01 M perchloric acid media takes place in two stages. The E12 of the more positive wave at +0.10 to −0.17 V S.C.E. is pH-dependent, E12=0.06–0.106 pH. Coulometry indicates a four-electron process, TcO4−+8 H++4 e−=Tc3+. A second wave at −0.73 V appears to involve the three-electron step (III) → (O). Technetium electrodeposits into mercury in a finely-divided form. Centrifugation of the product indicates particles of 10−5–10−6 cm diameter. A freshly-prepared technetium “amalgam” dropping-electrode showed no anodic polarographic activity in 0.1M HCl from −0.8 to +0.05 V S.C.E., indicating little solubility, or true amalgam character.
Acute Kidney Injury in Children Undergoing Correction of Congenital Heart Disease

Objective To assess risk factors of acute kidney injury in congenital cardiac disease following cardiac surgery with cardiopulmonary bypass in children. Methods A 50% postoperative creatinine increase was regarded as the criterion of acute kidney injury. 124 children aged 3 years or little undergoing cardiac surgery were divided into three groups: (1) negative AKI (-); (2) AKI (+) with an increase in postoperative creatinine from 150% to 200%; and (3) AKI (++) with an increase in postoperative creatinine by more than 200%. Demographics, and preoperative, intraoperative, and postoperative variables were evaluated for associations with AKI using univariate and multiple logistic regression analysis. Results Several variables, including mortality, preoperative albumin and creatinine levels, cardiopulmonary bypass duration, and postoperative creatinine levels, were significant differences among the three groups (P
THE PAIR POTENTIAL APPROACH FOR INTERFACES : FUNDAMENTAL PROBLEMS AND PRACTICAL SOLUTIONS

A fundamental problem in the use of a central pair-force model for defect problems is that it omits three-body and higher terms which are necessarily present in real systems. Electronic fluctuation effects are also usually omitted. While these can be small in the simple metals, they are significant in noble and transition metals, as shown by a simple real space argument. To guage the importance of their effects in interface problems, the structure of a simple sum 5 twist boundary is examined, with the atoms described by both pair- and three-center interactions and as a function of the relative strength of the two. 15 refs.
Transverse and longitudinal ultrasonic attenuation measurements of the superconducting energy gap in high-purity rhenium

The attenuation of transverse and longitudinal waves propagating along thec axis in high-purity rhenium has been measured in the normal and superconducting states. In the superconducting state the attenuation was compared with the simple BCS theory using as adjustable parameters the gap parameter and the residual attenuation atTc (for transverse waves). Using transverse-wave attenuation a gap parameter of 3.50±0.10 was found, while the longitudinal attenuation data yielded a gap parameter of 2.90±0.10. At present, the only apparent explanation for this difference is that the integrals for transverse-and longitudinal wave energy loss in an ultrasonic wave contain different azimuthal angle dependencies and thus average an anisotropic energy gap differently.
Evaluation of line transect sampling based on remotely sensed data from underwater video

Abstract We used underwater video in conjunction with the line transect method and a Fourier series estimator to make 13 independent estimates of the density of known populations of bricks lying on the bottom in shallows of Lake Huron. The pooled estimate of density (95.5 bricks per hectare) was close to the true density (89.8 per hectare), and there was no evidence of bias. Confidence intervals for the individual estimates included the true density 85% of the time instead of the nominal 95%. Our results suggest that reliable estimates of the density of objects on a lake bed can be obtained by the use of remote sensing and line transect sampling theory.
Convex optimal uncertainty quantification: Algorithms and a case study in energy storage placement for power grids

How does one evaluate the performance of a stochastic system in the absence of a perfect model (i.e. probability distribution)? We address this question under the framework of optimal uncertainty quantification (OUQ), which is an information-based approach for worst-case analysis of stochastic systems. We are able to generalize previous results and show that the OUQ problem can be solved using convex optimization when the function under evaluation can be expressed in a polytopic canonical form (PCF). We also propose iterative methods for scaling the convex formulation to larger systems. As an application, we study the problem of storage placement in power grids with renewable generation. Numerical simulation results for simple artificial examples as well as an example using the IEEE 14-bus test case with real wind generation data are presented to demonstrate the usage of OUQ analysis.
Insulin resistance in uremia: In vitro model in the rat liver using human serum to study mechanisms

Abstract We have previously demonstrated in a rat model of chronic uremia that the liver is resistant to insulin. To further investigate the mechanism(s) of insulin resistance in uremia, primary cultures of normal rat hepatocytes were incubated with varying dilutions ( 1 10 to 1 10,000 ) of sera from undialyzed end stage uremic and normal humans for 20 hours. We then studied insulin action, binding, and postbinding events. Dilutions of uremic sera as low as 1 1,000 rendered the hepatocytes resistant to maximal concentrations of insulin with regard to [14C]acetate incorporation into lipids. The dose response curve for insulin-stimulated [14C]aminoisobutyric acid uptake demonstrated a shift to the right in hepatocytes incubated with uremic sera when compared with those incubated with normal sera. The 125I-insulin binding sites and affinity, 125I-insulin internalization and degradation, insulin receptor structure, autophosphorylation of the insulin receptor, and its tyrosine-specific kinase activity were normal in the hepatocytes rendered resistant to insulin by uremic sera. However, these cells failed to generate the chemical mediator or second messenger of insulin action, as assessed by its ability to stimulate pyruvate dehydrogenase (PDH) in liver mitochondria from normal rats. We concluded that uremic sera renders normal rat hepatocytes resistant to insulin. Insulin resistance is a postinsulin receptor kinase defect possibly due to lack of the generation of the chemical mediator of insulin action. This in vitro cell model may be useful to further define the mechanism(s) and the serum factor(s) responsible for insulin resistance in uremia in the absence of complicating hormonal and substrate changes that occur in vivo.
Metabolism of testosterone-4-C14 by rat brain homogenates and subcellular fractions.

Abstract The metabolism of testosterone by rat brain homogenates and subcellular fractions has been investigated with the use of a radioactive substrate and a NADPH regenerating system. The findings indicated that a less polar metabolite, representing about a 6% conversion of the substrate, was the major end-product under the conditions utilized. A more polar peak of radioactivity was found to represent a 2.5 – 3.0% conversion of the substrate without the use of recovery factors. The less polar metabolite was found only in the microsomal fraction, whereas more polar metabolites were formed in both the microsomal and soluble fractions.
Unsteady viscous-inviscid interaction procedures for transonic airfoils using Cartesian grids

A viscous-inviscid interaction procedure for transonic airfoils using an Euler/integral boundary layer formulation and Cartesian grids is presented. The approach is based on a time dependent formulation for both the integral boundary layer equations and the Euler equations. Effects of upstream history on the shear stress are modeled by a time dependent rate equation derived from the turbulent kinetic energy equation. Results are presented for two of the test cases reported by Cook et al. (1979) for the RAE 2822 supercritical airfoil and one of the cases reported by Harris (1981) for the NACA 0012 symmetric airfoil. In general, the results are in good agreement with experiment.
A 3D digital map of rat brain

A three dimensional (3D) computerized map of rat brain anatomy created with digital imaging techniques is described. Six male Sprague-Dawley rats, weighing 270-320 g, were used in the generation of this atlas. Their heads were frozen, and closely spaced cryosectional images were digitally captured. Each serial data set was organized into a digital volume, reoriented into a flat skull position, and brought into register with each other. A volume representative of the group following registration was chosen based on its anatomic correspondence with the other specimens as measured by image correlation coefficients and landmark matching. Mean positions of lambda, bregma, and the interaural plane of the group within the common coordinate system were used to transform the representative volume into a 3D map of rat neuroanatomy. images reconstructed from this 3D map are available to the public via Internet with an anonymous file transfer protocol (FTP) and World Wide Web. A complete description of the digital map is provided in a comprehensive set of sagittal planes (up to 0.031 mm spacing) containing stereotaxic reference grids. Sets of coronal and horizontal planes, resampled at the same increment, also are included. Specific anatomic features are identified in a second collection of images. Stylized anatomic boundaries and structural labels were incorporated into selected orthogonal planes. Electronic sharing and interactive use are benefits afforded by a digital format, but the foremost advantage of this 3D map is its whole brain integrated representation of rat in situ neuroanatomy.
A Consistent Model for Thermal Fluctuations and Protein-Induced Deformations in Lipid Bilayers

We present an elastic Hamiltonian for membrane energetics that captures bilayer undulation and peristaltic deformations over all wavelengths, including the short wavelength protrusion regime. The model implies continuous functional forms for thermal undulation and peristaltic amplitudes as a function of wavelength and predicts previously overlooked relationships between these curves. Undulation and peristaltic spectra display excellent agreement with data from both atomistic and coarse-grained models over all simulated length scales. Additionally, the model accurately predicts the bilayer's response to a cylindrical protein inclusion as observed in coarse-grained simulation. This elastic response provides an explanation for gramicidin ion channel lifetime versus membrane thickness data that requires no fit constants. The physical parameters inherent to this picture may be expressed in terms of familiar material properties associated with lipid monolayers. Inclusion of a finite monolayer spontaneous curvature is essential to obtain fully consistent agreement between theory and the full range of available simulation/experimental data.
Fructus corni attenuates oxidative stress in macrophages and endothelial cells.

The antioxidant effect of a Chinese medicinal herb, Fructus corni extract (FCE), was investigated using models of oxidative stress in macrophages and vascular endothelial cells. Murine macrophages (J774) were incubated with FCE at 37°C and 5% CO2 for 1 hr. Oxidative burst was triggered by zymosan and measured with a fluorescent probe. FCE exhibited a concentration- dependent suppression of oxidative burst. Confluent monolayers of bovine pulmonary artery endothelial cells (PAEC) were preincubated with FCE for 20 hrs, washed, and then exposed to an organic oxidant t-butyl hydroperoxide (tBHP) for 2 hrs. Cell viability was assessed by methylthiazol tetrazolium (MTT) assay, and cell injury by the release of intracellular lactate dehydrogenase (LDH). Lipid peroxidation products of PAEC were determined by measuring thiobarbituric acid-reactive substances (TBARS). Exposure of PAEC to tBHP resulted in decreased cell viability, increased LDH release, and elevated TBARS. Preincubation of PAEC with FCE significantly reversed these changes. Our results demonstrated that FCE can protect vascular endothelial cells from oxidant injury. The data thus suggest that Fructus corni may be useful for the prevention and/or treatment of disorders associated with oxidative damage.
Reaction mechanism for the photopolymerization of solid fullerene C60

Abstract A photochemical “2+2 cycloaddition” reaction is proposed to drive the photopolymerization of pristine solid C 60 . This mechanism proceeds via the triplet T 1 state and exhibits a temperature threshold near 250 K, close to the orientational ordering transition of solid C 60 . Below this threshold, the topochemical requirement of reactive double bond alignment on adjacent C 60 molecules becomes improbable, thereby suppressing the reaction rate.
Apoptotic signaling by c-MYC

c-MYC has a pivotal function in growth control, differentiation and apoptosis, and its abnormal expression is associated with many tumors. Overexpression of c-MYC sensitizes cells to apoptosis by a variety of stimuli. The decision of a cell to undergo apoptosis and how this apoptotic response is regulated by c-MYC depends on the specific cell type and the physiological status of the cell. Multiple cooperating molecular pathways of cell survival and apoptosis determine whether a cell lives or dies, and understanding how c-MYC interfaces with these pathways to influence the survival of cells is important to understand normal and abnormal development, tumor initiation and progression, and response of tumors to different treatment regimens. This article will provide an overview of the function of the tumor suppressor gene product p53 in the c-MYC-mediated apoptotic response and how c-MYC amplifies the intrinsic mitochondrial pathway and triggers and/or amplifies the death receptor pathways. Finally, a model for how deregulated c-MYC prematurely triggers the normal apoptotic response associated with terminal myeloid differentiation while also blocking the differentiation program is presented.
A pharmacodynamic study of (14C)thiourea toxicity in mature, immature, tolerant, and nontolerant rats.

Abstract Radioautographic localization of [ 14 C]thiourea (TU) in rat lung 24 hr post ip administration indicates uniform distribution in alveolar walls. Lung parenchymal tissue may, therefore, be a target area for TU binding and toxicological effects. Immature and tolerant rats bind less radioactivity from [ 14 C]TU in their lungs than do mature or nontolerant rats. This may partially explain the refractoriness of these animals to the lethal pulmonary edematogenic effect of TU. Differences in binding characteristics or subcellular localization of [ 14 C]TU were not observed. Immature, mature, tolerant, and nontolerant rats all excrete urinary [ 14 C]TU in the same amount and at the same rate. If an active intermediate is responsible for the toxicological effect of TU in the lung, then it is probably not formed by liver drug microsomal metabolism since induction of this system with phenobarbital did not alter lung binding. In addition, tolerance to the toxic lung effect of TU does not appear to involve enhanced oxidative inactivation by the liver since pretreatment with TU produced no change in hepatic cytochrome P-450. The possibility remains, however, that formation of a labile metabolite may occur in the lung itself.
Moisture Uptake and Outgassing in Patterned and Capped Porous Low-k Dielectric Films

The interactions of moisture with spin-on porous methylsilsesquioxane (p-MSQ) low-k dielectric films are investigated by on-line and real-time measurement of the rates of moisture uptake and removal. A process model is developed that provides information on the dynamics of moisture adsorption and desorption processes. The process model can be used to find optimum purge temperature and gas purity condition for cleaning and drying of low-k films. The cured p-MSQ films are compared with the partially etched and N 2 H 2 ashed films. The results show that these two films have similar moisture solubilities; however, the moisture diffusivity in the patterned film is considerably higher. Transmission electron microscope results show that the etching and ashing processes not only decrease the overall film thickness but also increase the film porosity. The process model also provides information on moisture distribution within the film; this information is important in characterizing residual moisture and interfacial adhesion. The results for a wide range of diffusivity show that thin cap layers with low moisture solubility effectively block moisture penetration into the p-MSQ film without slowing down the outgassing and moisture removal during the purge.
Fine structure of perifollicular nerve endings in human hair.

Perifollicular nerve endings of the human lanugo hairs have been studied with the electron microscope. The endorgans are arranged in palisade along the periphery of the follicle and are composed of an axon and an enveloping Schwann sheath. Spaces between the endorgan are largely free from collagen and cellular elements. This arrangement of endorgans perpendicular to the follicle may be most efficient to detect the movement of the follicle, and the empty spaces between the organs permit a maximum deformation of the terminal axon. The axon produces a subcytomembrane dense layer at the follicular end but is, with rare exceptions, separated from the external root sheath cells by the basal lamina. The endorgan can attach to any portion of the follicle including the cellular junctions, indicating that there is no specialization on the follicular side at the site of attachment. In fact, half-desmosomes and subbasal dense plaques are regularly seen on the basal surface of the follicular basal cells.
Changes in Column Ozone Correlated with the Stratospheric EP Flux

Variability in planetary wave forcing from the troposphere to the stratosphere is reflected in changes in ozone transport, due to fluctuations in the stratospheric Brewer-Dobson circulation and eddy mixing. This work examines the space-time patterns of correlations between column ozone tendency and planetary wave Eliassen-Palm (EP) flux into the lower stratosphere, using monthly mean data for 1979-2000. Strong correlations are found during winter-spring in both hemispheres, with out-of-phase ozone changes between the tropics and middle-high latitudes. Springtime polar ozone is strongly influenced by wave forcing in both the Arctic and Antarctic. The ozone tendency-wave forcing correlations are combined with observed variations in EP flux to estimate the dynamic contribution to decadal-scale NH ozone trends. These calculations suggest that interannual changes in EP flux contribute ∼20-30% of the observed trends in column ozone over 35-60°N during the past two decades.
Transportation as a Component of National Urban Strategy

The purpose of national urban policy planning is to recommend distributions of population, infrastructure investment, and productive economic investment across national space. This is to address national development objectives, such as increased productivity, improved regional equity, enhanced social equity, and so forth. There is obviously a transportation component. Many national transportation studies have been done in the developing world with some attention to serving the development of a system of cities, Over the last 25 years useful experience has been gained. The target dates of the studies have tended lately to draw towards a sensible lo-15 years, rather than including only immediate action needs plus recommendations for futuristic distant target dates. A perspective on transportation as a system has evolved in these studies, while they still include separate issue analyses. The technical complexity of the studies has evolved towards a level that takes advantage of the state of the art, while at the same time considering the limitations of the data and data quality (Houel).2 These plans have generally had sections on (1) removing administrative deficiencies in the supply of transportation services and facilities, (2) urgent programmes to remove system bottlenecks, and (3) serving projected future demand. The field has only slowly moved towards multimodal integration. An important contribution towards that objective has been made by Kanafani’s textbook on national transportation planning.3 Studies have shown very limited attention to relating transportation to other spatial development decisions and have made little effort to deal with the role of urban transportation in this large context. This paper will lay out four critical problems of including transportation in national urban policy planning. It will then propose a framework for transportation in national urban policy planning that provides one response to each of *This is an edited version of a paper presented at the 9th EAROPH International Congress, 20-24 August
Timing of Retroviral Infection Influences Anamnestic Immune Response in Vaccinated Primates

Using simian immunodeficiency virus (SIV) infection of rhesus macaques to model human immunodeficiency virus (HIV) infection of humans, we assessed whether broadly reactive vaccine-induced humoral immunity would remain broadly reactive after viral challenge, and whether there would be significant differences in anamnestic antibody responses if animals were challenged when predominately effector or memory lymphocyte populations were present. Animals immunized over a prolonged period and challenged 11 months after vaccination mounted more broadly reactive and stronger humoral immunity than those rapidly vaccinated and challenged 2 weeks after their final vaccinations. These data suggest that vaccination schedule and the timing of virus challenge should be considered when evaluating future candidate HIV vaccines.
Degenerate Regge trajectories and parity doublets of baryon resonances

Abstract The MacDowell reflection symmetry as applied to Regge recurrences of SU(3) multiplets is suggested as a natural explanation of recent experimental observations of parity doublets of baryon resonances (resonance pairs with approximately equal masses, the same Y , I and J values and opposite parities).
Simultaneous perfusion and permeability measurements using combined spin- and gradient-echo MRI.

The purpose of this study was to estimate magnetic resonance imaging-based brain perfusion parameters from combined multiecho spin-echo and gradient-echo acquisitions, to correct them for T1-, T2-, and -related contrast agent (CA) extravasation effects, and to simultaneously determine vascular permeability. Perfusion data were acquired using a combined multiecho spin- and gradient-echo (SAGE) echo-planar imaging sequence, which was corrected for CA extravasation effects using pharmacokinetic modeling. The presented method was validated in simulations and brain tumor patients, and compared with uncorrected single-echo and multiecho data. In the presence of CA extravasation, uncorrected single-echo data resulted in underestimated CA concentrations, leading to underestimated single-echo cerebral blood volume (CBV) and mean transit time (MTT). In contrast, uncorrected multiecho data resulted in overestimations of CA concentrations, CBV, and MTT. The correction of CA extravasation effects resulted in CBV and MTT estimates that were more consistent with the underlying tissue characteristics. Spin-echo perfusion data showed reduced large-vessel blooming effects, facilitating better distinction between increased CBV due to active tumor progression and elevated CBV due to the presence of cortical vessels in tumor proximity. Furthermore, extracted permeability parameters were in good agreement with elevated T1-weighted postcontrast signal values.
Reproducibility of exercise-induced ventricular arrhythmia in patients undergoing evaluation for malignant ventricular arrhythmia

In patients with malignant ventricular arrhythmia, the utility of exercise testing for exposing arrhythmias and guiding antiarrhythmic drug selection and dosage is not yet generally accepted. A major reservation relates to the issue of reproducibility of arrhythmia provocation. This prospective study comprised 28 patients referred for evaluation of ventricular arrhythmia. In half of these subjects the clinical arrhythmia was sustained ventricular tachycardia or ventricular fibrillation. Maximal exercise testing adhering to a Bruce protocol was performed on 2 separate days. No antiarrhythmic drugs were administered at the time of testing. Of the 28 patients, 27 had an increase in arrhythmia with exercise. The prevalence rates of arrhythmia were greater than 80% and did not significantly differ between test 1 and test 2. Excluding infrequent single ventricular premature complexes, the reproducibility of a test with positive outcome was 76%. Similarly, test-retest agreement, a bidirectional measure of reproducibility, was greater than 74%. Kappa coefficients ranged from 0.26 to 0.36 for all grades of arrhythmia, indicating that reproducibility was consistently greater than by chance alone. Linear regression analysis of arrhythmia frequency in the 2 tests yielded R values of 0.76 to 0.96 and slopes of 0.82 to 1.2. No patient had enough spontaneous variability in repetitive forms to suggest spurious efficacy or aggravation. For ventricular premature complexes there was an 8 to 14% incidence of spurious efficacy and a 4 to 7% incidence of spurious aggravation. These results suggest that exercise-induced ventricular arrhythmia is sufficiently reproducible to serve as an adjunct method in the evaluation and management of patients with potentially life-threatening ventricular arrhythmias.
Chemical modification of dopamine β-hydroxylase

Abstract Dopamine β-hydroxylase (3,4-dihydroxyphenylethylamine, ascorbate:oxygen oxidoreductase (β-hydroxylating), EC 1.14.17.1) is the terminal enzyme in the biosynthetic pathway of norepinephrine. Chemical modification studies of this enzyme were executed to investigate contributions of specific amino-acid side-chains to catalytic activity. Sulfhydryl reagents were precluded, since no free cysteine residue was detected upon titration of the denatured or native protein with 2-chloromercuri-4-nitrophenol. Incubation of enzyme with diazonium tetrazole caused inactivation of the protein coupled with extensive reaction of lysine and tyrosine residues. Reaction with iodoacetamide resulted in complete loss of enzymatic activity with reaction of approximately three histidine residues; methionine reaction was also observed. Modification of the enzyme using diethylpyrocarbonate resulted in complete inactivation of the enzyme, and analysis of the reacted protein indicated a loss of approx. 1.7 histidine residues per protein monomer with no tyrosine or lysine modification observed. The correlation of activity loss with histidine modification supports the view that this residue participates in the catalytic function of dopamine β-hydroxylase.
Fracture toughness of a soft sandstone

Abstract Fracture toughness of a rock/material is important in the design of rock drilling/boring equipment, rock bursting, prediction of rock drilling forces, hydraulic fracturing, wellbore stability and stability of jointed rock masses. A series of fracture toughness tests under mode-I, mode-II and mixed-mode (I–II) loading conditions were conducted on straight-edge notch Brazilian disk (SENBD) specimens in an attempt to develop an empirical failure envelope under both tension-shear and compression-shear conditions. This series of tests is the first of its kind on a naturally weakly-cemented Antler sandstone. Even though there have been published data on artificially cemented sandstones, there are no data on mixed-mode fracture toughness of such soft formations. The SENBD specimen configuration used herein provides consistent failure patterns and development of a failure envelope in the compression-shear zone, as well. Microscopic studies using thin sections of tested and untested specimens were carried out to study the fracture propagation at micro-level.
Turning Meat, Poultry, Eggs, and Dairy Products Into Nutraceuticals Through Increasing Their Conjugated Linoleic Acid Levels, Part One: Reviewing the Literature of Benefits Claimed for Conjugated Linoleic Acids in Human Health

ABSTRACT In the first of this two-part series of articles, the debate in the clinical literature over the reality or extent of particular positive health benefits of a putative nutraceutical, conjugated linoleic acids (CLAs), in human subjects will be reviewed. In the second article, the means by which animal scientists and farmers—responding as much to annual sales in the hundreds of millions of dollars in health food stores of seed oil capsules rich in CLAs, as opposed to any conclusive clinical science—are aggressively pursuing ways to feed livestock that would naturally increase the concentration of CLAs per conventional consumer dietary portions, essentially allowing meat, eggs, fluid milk and the processed foods derived from them to be marketed as functional foods. In both installments in this series, the core journals covering developments in CLA-related research are identified for agricultural and food science librarians.
Lethality and bioaccumulation of 4-nonylphenol in bluegill sunfish in littoral enclosures

Toxicity and bioaccumulation in bluegill sunfish (Lepomis macrochirus) of 4-nonylphenol (NP), a common precursor and degradation intermediate of certain nonionic surfactants, were evaluated in a set of 18 aquatic mesocosms (littoral enclosures) in northeastern Minnesota. Nonylphenol was applied to enclosures every 48 h over a 20-d period (11 applications) at rates of 3, 30, 100, and 300 {micro}g/L. Additional enclosures served as untreated controls. Maximum NP levels in the integrated water column 2 h after each application averaged 5 {+-} 4, 23 {+-} 11, 76 {+-} 21, and 243 {+-} 41 {micro}g/L over the 11 applications at the 3-, 30-, 100-, and 300-{micro}g/L treatments, respectively. Sixty-one percent of the NP dissipated from the water column within {approximately} 39 h of each application. Estimated survival of stocked juvenile bluegills was significantly reduced at the 300-{micro}g/L NP treatment. No significant effects were noted at the other NP treatments; however, the 100-{micro}g/L enclosure with the highest mean NP concentration (93 {+-} 39 {micro}g/L) within that treatment had four to nine times more dead bluegills and four to six times fewer bluegills captured at the end of the season than the other two 100-{micro}g/L enclosures (64 {+-} 23 and 71 {+-} 32 {micro}g/L) andmore » the controls, suggesting increased mortality in this enclosure. Nonylphenol tissue concentrations in juvenile bluegills collected from enclosures treated with 3 and 30 {micro}g/L NP ranged from 0.01 to 2.94 {micro}g/g wet weight and showed a significant positive relationship with the average measured NP concentration in the water. The mean wet weight nonequilibrium NP bioaccumulation factor was 87 {+-} 124. There was no relationship between fish lipid content and NP tissue concentration.« less
The Structures of Antibiotics Bound to the E Site Region of the 50 S Ribosomal Subunit of Haloarcula marismortui: 13-Deoxytedanolide and Girodazole.

Crystal structures of the 50 S ribosomal subunit from Haloarcula marismortui complexed with two antibiotics have identified new sites at which antibiotics interact with the ribosome and inhibit protein synthesis. 13-Deoxytedanolide binds to the E site of the 50 S subunit at the same location as the CCA of tRNA, and thus appears to inhibit protein synthesis by competing with deacylated tRNAs for E site binding. Girodazole binds near the E site region, but is somewhat buried and may inhibit tRNA binding by interfering with conformational changes that occur at the E site. The specificity of 13-deoxytedanolide for eukaryotic ribosomes is explained by its extensive interactions with protein L44e, which is an E site component of archaeal and eukaryotic ribosomes, but not of eubacterial ribosomes. In addition, protein L28, which is unique to the eubacterial E site, overlaps the site occupied by 13-deoxytedanolide, precluding its binding to eubacterial ribosomes. Girodazole is specific for eukarytes and archaea because it makes interactions with L15 that are not possible in eubacteria.
Justice and the Foundations of Social Morality in Hume's Treatise

Soulevant la question de la psychologie morale au fondement du sens de la justice et de l'appreciation des vertus artificielles, l'A. propose une lecture du «Traite de la nature humaine» qui s'eloigne de l'interpretation des attitudes sociales developpee par B. Stroud et qui distingue la position humeenne de la psychologie essentialiste de ses contemporains (Hutcheson et Hobbes). A partir d'une reconstruction de l'idee d'une morale pre-culturelle ou pre-conventionnelle chez Hume, l'A. montre que les conventions concernant la justice incarnent certaines interactions sociales regies par la loi qui nous incitent a developper une conception commune de l'interet public par rapport a laquelle se determinent nos perspectives evaluatives
Phase space features and statistical aspects of forward - Backward semiclassical dynamics

Forward-backward semiclassical dynamics (FBSD) has emerged as a practical quasiclassical methodology for including important quantum mechanical effects in the initial state of a system, while retaining a classical description of the subsequent dynamics. FBSD expressions for time correlation functions or expectation values constitute rigorous stationary phase limits of the corresponding quantum mechanical quantities but can be evaluated with relatively little computational power. While allowing the inclusion of important effects such as zero point energy, the mixing of a quantum mechanical representation of the initial condition with a classical treatment of the dynamics is at least in principle inconsistent. In this paper we investigate various manifestations of this issue. Specifically, we examine the classical evolution of the quantized FBSD phase space density and the validity of the detailed balance condition in model systems. Our findings indicate that the practical consequences of the inconsistent quantum-classical treatment generally are of minor significance and suggest specific tests for checking the accuracy of FBSD calculations in polyatomic systems.
Enterohepatic circulation of cholic acid and cholesterol metabolism in the rat

A role for cholic acid in the regulation of body cholesterol levels is emphasized by the following experiment and findings. Fifteen rats with biliary and duodenal fistulae were divided into three groups. 4-14C-cholesterol was admistered intravenously to all animals on day 1. Two groups received a duodenal infusion of either sodium taurocholate or of cholesterol at the same time and thereafter daily. Bile samples were collected daily for 15 consecutive days. Cholic, chenode-oxycholic acid and cholesterol were the major labeled compounds in the bile. Labeled cholic acid disappeared from the bile of control animals after day 8 while it persisted in the group receiving unlabeled cholic acid up to day 15. The decrease of specific radioactivity of labeled biliary cholic acid in the rats receiving unlabeled cholesterol corresponded to that of control animals. A significant increase in the concentration of cholesterol was found in the plasma of animals receiving cholic acid and in the liver of those receiving unlabeled cholesterol.
Antiferromagnetism in Rb2MnCl4·2H2O

Abstract Specific heat measurements in the temperature range 1.38° – 4.03°K indicated a λ-type anomaly at 2.24°K which has been identified as a paramagnetic-antiferromagnetic transition. Short range ordering accounts for approximately 25% of the total entropy change. The calculated sublattice magnetization is compared to several statistical models.
Fuzzy weighted averages and implementation of the extension principle

Abstract This paper addresses the computational aspect of the extension principle when the principle is applied to algebraic mappings and, in particular, to weighted average operations in risk and decision analysis. A computational algorithm based on the α-cut representation of fuzzy sets and interval analysis is described. The method provides a discrete but exact solution to extended algebraic operations in a very efficient and simple manner. Examples are given to illustrate the method and its relation to other discrete methods and the exact approach by non-linear programming. The algorithm has been implemented in a computer program which can handle very general extended algebraic operations on fuzzy numbers.
A systems framework for globalisation

Globalisation is widely acknowledged as a phenomenon affecting the environment in significant ways. The attention given to it by different academic disciplines underscores its multidimensionality and complicates our ability to analyse its impact. This paper argues that the systems approach provides the tools to both frame globalisation as well as provide guidelines for analysis. Globalisation is presented as comprising of five domains – political, economic, social, business and physical. The paper then describes the use of systems thinking through the importance of goal identification/setting performance measures, boundary delineation, the nature of interactions between the domains, and trends in convergence/divergence. This approach leads to a more systematic decision making process in the context of globalisation.
INFLUENCE OF LIFE-PROLONGING DIETARY RESTRICTION ON INTESTINAL VITAMIN A ABSORPTION IN MICE

We studied influences of life prolonging dietary restriction on the absorptive capacity of the small intestine for the lipid micronutrient, Vitamin A. Using a well established intestinal perfusion technique, we measured the vitamin absorption rates in vivo in male mice fed regular laboratory chow (LC) ad lib, female mice on 95 kcal/week of a semipurified diet (designated “N” for normally fed), and female mice restricted to a 55 kcal/wk diet fed four days per week (R). The absorption rate of vitamin A was the lowest in LC mice and highest in R mice. Both at 6 and 26 months of age, R mice absorbed significantly more vitamin A than did the N mice. For example, at 6 months, R mice absorbed 10696 pmol/100 cm/hr while N mice absorbed only 7986 pmol/100 cm/hr (p<.01). Thus, dietary restriction increased the absorptive capacity of the small intestine for the lipid micronutrient vitamin A. The mechanisms responsible remain unknown, but could involve changes in the unstirred water layer resistance or in the lipid cell membrane of the enterocytes.