cssi/SciSciGPT-SciSciNet huggingface dataset:
Urate produced during hypoxia protects heart proteins from peroxynitrite-mediated protein nitration.

Abstract Tyrosine nitration is a common modification to proteins in vivo, but the reactive nitrogen species responsible for nitration are often studied in vitro using just the amino acid tyrosine in simple phosphate solutions. To investigate which reactive nitrogen species could nitrate proteins in a complex biological system, we exposed rat heart and brain homogenates to peroxynitrite, nitric oxide under aerobic conditions, and other putative nitrating agents. Peroxynitrite was by far the most efficient nitrating agent when alternative targets were available to compete with tyrosine. Curiously, proteins in heart homogenates were substantially more resistant to nitration than brain homogenates. Ultrafiltration to remove low molecular weight compounds made the heart proteins equally susceptible as the brain proteins to nitration. Endogenous ascorbate and free thiols had little effect on nitration by peroxynitrite in either heart or brain. However, accumulation of urate formed by the oxidation of hypoxanthine by xanthine dehydrogenase and oxidase in heart appeared to be the major inhibitor of nitration. Heart homogenates treated with uricase, which converts urate to allantoin, showed equivalent nitration as in brain homogenates. Urate, as assayed by HPLC, was 58 ± 8 μM in heart but only 4 ± 2 μM in brain homogenates. Although xanthine dehydrogenase conversion to a free radical-producing oxidase can serve as an important source of superoxide and hydrogen peroxide during ischemia/reperfusion, our results suggest that urate formation by xanthine dehydrogenase may provide a significant antioxidant defense against peroxynitrite and related nitric oxide-derived oxidants.
Forward directed Smith-Purcell radiation from relativistic electrons.

The requirements for the generation of forward directed Smith-Purcell emission from relativistic electrons are introduced, and the first experimental evidence of this phenomenon is presented. The experiments were conducted with a 2.8 MeV/ $c$ electron beam interacting with a 1 cm period grating. Radiation emitted in two bands with wavelengths ranging from 600 to 650 $\ensuremath{\mu}$m and 1.2 to 1.7 mm were measured. Grating period to wavelength ratios were as high as 16. The measured intensities are higher than that predicted by incoherent emission.
How did mathemathematics and accounting get so many women majors?: what can IT disciplines learn?

Enrollment of women in Information Technology (IT) disciplines is shrinking. Disciplines that were traditionally male, mathematics and accounting, have succeeded in gaining equal numbers of male and female students. This paper looks at the changes in these two disciplines to see whether similar changes might be used to attract and retain women students in IT disciplines. An overview of the gender transformation of Math and Accounting provides a list of shared strategies used to attract women. A comparison of the three disciplines provides insight for attracting women to IT.
Cerebral physiological and metabolic effects of hyperventilation in the neonatal dog

To clarify the changes that occur during marked hypocarbia in the neonate, we measured brain blood flow and metabolite levels after 90 minutes of hyperventilation in neonatal dogs. Brain blood flow decreased significantly in diencephalon, brainstem, and spinal cord but not in cerebral cortex or white matter. There was no substantial change in the electroencephalogram. Lactate concentrations, both in telencephalon and in superior sagittal sinus blood, increased significantly, although there was no alteration in levels of ATP or phosphocreatine. Marked hypocarbia in the neonatal dog produces an elevated brain lactate level that may be related to changes in glycolytic rate rather than to tissue ischemia or hypoxia.
The optical jet of 3C273: an electron–positron plasma beam viewed by the light of its quasar?

The nearby bright quasar 3C273 has an extended multiband jet whose spatial pattern of intensity differs strongly from band to band. We propose that only the radio power of the jet is accounted for by the usual synchrotron model. All the higher energy photons seen are instead secondary, misdirected photons from the bright quasar core scattered our way by material within the jet. This model gives a good account of form, spectrum, polarization and intensity pattern along the jet in all the higher bands. Dust cannot plausibly scatter the X-rays seen, but Thomson scattering fits all bands well
Effects of olfactory bulbectomy and estrogen on tyrosine hydroxylase and glutamic acid decarboxylase in the nigrostriatal and mesolimbic dopamine systems of adult female rats.

Abstract Following olfactory bulbectomy (BULBX), ovariectomized female rats show enhanced behavioral sensitivity to estradiol benzoate (EB) as measured by an index of sexual receptivity, lordosis responding. We have proposed previously that alterations in EB sensitivity which also are produced by septal destruction reflect disruptions of gamma-aminobutyric acid (GABA) inhibitory feedback on dopamine (DA) cell bodies in the midbrain, which may be inhibitory to the expression of lordosis. Since the olfactory system as well as the septum receives mesolimbic DA projections, in the present study we examined the effects of EB given to bulbectomized and sham-operated rats on tyrosine hydroxylase (TH) activity in the olfactory tubercle (OT), nucleus accumbens septi and corpus striatum. Glutamic acid decarboxylase (GAD) activity was measured in the ventral tegmental region (VTR) and the substantia nigra (SN). Rats received 2 μg EB/day for 3 days and were tested on Day 4 in a 20 mount behavioral test. Ten bulbectomized rats demonstrating enhanced behavioral sensitivity to EB and all sham-operated rats (N = 10) were selected for further study. Five rats in each group received 0.05 ml oil/day X 3 (BULBX-oil, SHAM-oil), and five received 2 μg EB/day X 3 (BULBX-EB, SHAM-EB). Rats were sacrificed on Day 4. Subsequent assays revealed a bulbectomy-dependent decrease in TH activity in the striatum, and a lesion plus EB-dependent decrease in TH activity in the OT. GAD activity was slightly but significantly suppressed in the VTR in the SHAM-EB group relative to that in the SHAM-oil group. Rats of the BULBX-EB group failed to exhibit decreased GAD activity. Thus, bulbectomy may result in enhanced behavioral sensitivity to EB due to disruptions in GABA-DA interactions, which are similar to those observed following septal destruction and which result in diminished behaviorally inhibitory DA tone.
The Effect of CO2 Concentration on the Frequency of Blocking in a General Circulation Model Coupled to a Simple Mixed Layer Ocean Model

Abstract The effect of a doubling of atmospheric CO2 on the characteristics of the 500 mb height field and persistent height anomalies associated with blocking phenomena are investigated in two experiments with the NCAR Community Climate Model (CCM) coupled to a simple ocean mixed layer. This version of the CCM with a seasonal cycle, computed hydrology and the simple mixed layer ocean produces a somewhat improved simulation compared with earlier model versions in spite of a lack of ocean heat transport and overextensive sea ice. In a control experiment with present amounts of CO2, 500 mb height statistics compared best with observations during winter while summer is not simulated as well. In a second experiment, where CO2 is doubled, the troposphere experiences warming most everywhere and 500 mb heights increase, especially near areas where sea ice has retreated and surface air temperature warming is greatest. In most regions of significant blocking activity, standard deviations of 500 mb height and block...
Calculating boson and fermion loops in 3+1 dimensions and the derivative expansion

We extend our work on the numerical calculation of one-loop quantum corrections from two to four space-time dimensions, using a Green's-function technique. Studying time-independent, spherically symmetric background fields, we illustrate this method by calculating one-boson-loop and one-fermion-loop quantum corrections to the energy. We use our results to test derivative expansions and illuminate their convergence properties.
SIMULTANEOUS DESIGN OF CONTROL AND STRUCTURAL SYSTEMS

Abstract A numerical algorithm for simultaneous optimization of control and structural systems is proposed, analyzed and evaluated in this paper. In the procedure, the structural and control design subproblems are solved in a sequence. In the outer loop, it is proposed to solve the constrained structural optimization problem using the nonlinear programming ( NLP) approach, and in the inner loop, the control design problem is proposed to be solved using the differential dynamic programming ( DDP) approach. For the optimal control design problem, the functional and pointwise state variable constraints are treated using the augmented Lagrangian approach. The resulting unconstrained control design subproblem is then solved using the DDP approach which has been determined to be more efficient than the NLP approach for this class of problems. The basic ideas of the augmented Lagrangian and the DDP approaches are explained. The proposed approach is quite general as it can treat linear as well as nonlinear system...
Physical determinants of strong voltage sensitivity of K(+) channel block.

Inward-rectifier K+ channels respond to voltage via blockage by intracellular polyamines. How these blockers work is not entirely clear. Now a crystal structure of the cytoplasmic portion of Kir3.1 reveals five ion sites, and functional analyses indicate these ions are displaced by spermine binding.
Reduction in resident microflora, and experimentally inoculated Salmonella enterica, on spinach leaves treated with vinegar and canola oil.

In this study, we explored the use of vinegar, or vinegar and canola oil as a salad dressing, to reduce bacterial levels on spinach leaves. We found that incubation of spinach leaves with various types of vinegar substantially reduced the predominantly gram-negative microflora. A similar response was observed when spinach leaves were incubated with white vinegar mixed in various proportions with canola oil, as used in salad dressing. We assessed the effects of vinegar, or vinegar and oil, on spinach leaves that had been experimentally inoculated with a cocktail of Salmonella enterica strains. Allowing the mixture to sit at room temperature for at least 20 min resulted in a substantial reduction (up to 2.0 log CFU) in numbers of S. enterica. Vinegar and oil caused a limited reduction in CFU (0.5 log) for spinach leaves experimentally inoculated with a cocktail of Listeria monocytogenes strains. These findings suggest that mixing spinach leaves with vinegar and oil as a salad dressing can reduce the bacteri...
Endogenous sex hormones, blood pressure change, and risk of hypertension in postmenopausal women: The Multi-Ethnic Study of Atherosclerosis

Objective Sex steroid hormones have been postulated to involve in blood pressure (BP) regulation. We examine the association of endogenous sex hormone levels with longitudinal change of BP and risk of developing hypertension in initially normotensive postmenopausal women.
Expression of fetal isoforms of actin after transplantation injury

Trauma and injury to transplanted organs in the early post-transplant period are significant factors that affect long-term graft survival. Fetal isoforms of actin are integral members of the immediate early gene family and are expressed in response to free radical injury. We therefore studied actin gene expression in heart transplantation to determine if reperfusion injury activates fetal isoforms of actins. Heterotopic cardiac transplantations were performed in mice. mRNA was extracted from allo- and isografted hearts as well as from normal hearts and spleen. Northern hybridization with actin cDNA to α and β/γ actin mRNA was performed and analyzed by densitometry. The β/γ actin gene expression in the transplanted hearts was found to be significantly elevated within 48 h after transplantation. Analysis of β/γ actin gene expression in isografts substantiates the possibility of de novo increase in actin expression.Our studies demonstrate for the first time that fetal isoforms of actin are induced in the allograft heart after transplantation.
Stereoscopic acuity for photometrically matched background wavelengths at scotopic and photopic levels

Two Ss made equidistance settings in a two-rod apparatus using white and four chromatic (red, yellow, Feen, and blue) backgrounds, photometrically matched at each of eight or nine teat levels within a total retinal-illuminance range of 4 log units. The binocular depth setting were analyzed in terms of the angular magnitude of both the Yariable error, ηAD, and the constant error, ηΔR When ηAD is plotted as a function of retinal illuminance, the curves for each of the four chromatic IIIId white backlfound coditions show that at low retinal illuminances, ηAD, is initially large, and with increasing background illumination, ηAD progressively decreases to approach a final low asymptotic value. As predicted by the duplicity theory of vision, each experimental curve shows a dircontinulty at about −1.0 lot td (corresponding to a background luminance value of about 0.0069 fL with the 2.5-mm artificial pupil used) reflecting the transition from rod to cone functioning. The curves representing the different wavelengths essentially overlap throughout the total illumination range, indicating that, for both rod and cone vision, wavelength has no differential effect on the variability of depth settings. The data for ηΔR are less regular than those for ηAD and the rod-cone discontinuities appear less pronounced. The data are analyzed in terms of the relative contribution of the rod and cone mechanisms to performance level.
Structure and different conformational states of native AMPA receptor complexes

Ionotropic glutamate receptors mediate fast excitatory synaptic transmission in the central nervous system. Their modulation is believed to affect learning and memory, and their dysfunction has been implicated in the pathogenesis of neurological and psychiatric diseases. Despite a wealth of functional data, little is known about the intact, three-dimensional structure of these ligand-gated ion channels. Here, we present the structure of native AMPA receptors (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid; AMPA-Rs) purified from rat brain, as determined by single-particle electron microscopy. Unlike the homotetrameric recombinant GluR2 (ref. 3), the native heterotetrameric AMPA-R adopted various conformations, which reflect primarily a variable separation of the two dimeric extracellular amino-terminal domains. Members of the stargazin/TARP family of transmembrane proteins co-purified with AMPA-Rs and contributed to the density representing the transmembrane region of the complex. Glutamate and cyclothiazide markedly altered the conformational equilibrium of the channel complex, suggesting that desensitization is related to separation of the N-terminal domains. These data provide a glimpse of the conformational changes of an important ligand-gated ion channel of the brain.
Time-of-flight studies on compensated aSi:H

Abstract A discussion is presented, within the framework of the multiple trapping (MT) model of the measured changes in time of flight (TOF) parameters obtained on compensated aSi:H films. We also examine how discrepancies between the accepted models for hole transport in aSi:H and experimental data could be reconciled by slight modifications of the exponential localized tail state distribution.
Human Immunodeficiency Virus Type 1 Infection of Human Monocytes and Macrophages Does Not Alter Their Ability to Generate an Oxidative Burst

Human immunodeficiency virus type 1 (HIV-1) infects mononuclear phagocytes, cells that may serve as a reservoir for viral persistence. Infection with HIV-1 leads to progressive compromise of the immune system, resulting in infections with opportunistic pathogens and eventual death. Experiments were designed to determine if in vitro HIV-1 infection of mononuclear phagocytes would diminish their oxidative capabilities, thus decreasing their antimicrobial effectiveness. Blood monocytes and peritoneal macrophages were obtained from uninfected donors and inoculated with a monocytotropic strain of HIV-1. Hydrogen peroxide production and reduction of nitroblue tetrazolium were measured after acute stimulation of cells with PMA or a phagocytic stimulus. Despite vigorous virus production, no difference was seen in oxidative burst between uninfected cells and infected cells or between monocyte-derived and peritoneal macrophages. In conclusion, reduced antimicrobial activity of HIV-infected mononuclear phagocytes is probably not secondary to decreased ability to generate reactive oxygen species.
Late Quaternary paleoclimates and biotic responses in eastern North America and the western North Atlantic Ocean

Abstract Broad-scale late Quaternary paleoclimatic changes are interpreted from palynological records across eastern North America and from assemblages of marine Foraminifera in the western North Atlantic Ocean. Quantitative reconstructions of past dominance for major tree taxa at eight fossil-pollen sites, located south of the maximum glacial extent in the southeastern United States, illustrate dramatic responses of tree populations to climatic change during the transition from Pleistocene to Holocene conditions. A series of maps depicting changes in inferred boundaries of predominant airmasses during the late Quaternary are based upon paleoclimatic interpretation of paleovegetation maps for eastern North America, and CLIMAP maps of winter sea-surface temperatures for the western North Atlantic Ocean. In the eastern United States, at 18, 000 B.P. strong zonal circulation resulted in a fixed position of the atmospheric Polar Frontal Zone along 33°N latitude. The Pacific Airmass extended from 33°N latitude north to the southern margin of the Laurentide Ice Sheet, with the Maritime Tropical Airmass dominating south of 33°N across the Gulf Coastal Plain, the Gulf of Mexico, and the equatorial Atlantic Ocean. The oceanic Polar Frontal Zone extended northeastward from Cape Hatteras to 37°N in the western North Atlantic Ocean. Late glacial climatic amelioration was first reflected in vegetational changes south of the Laurentide Ice Sheet beginning at 16,500 B.P. Late glacial weakening in zonal atmospheric flow resulted in the penetration of the Maritime Tropical Airmass farther to the north during the summer season. Increased summer warmth and rain produced substantial melting of the southern flank of the Laurentide Ice Sheet. The early Holocene interval, from 12,500 to 8,000 B.P., bracketed the time of maximum seasonality of solar radiation, ca. 11,000 B.P. During the early Holocene, enhanced meridional air flows resulted in increased seasonality of temperatures. By 10,000 B.P., the oceanic Polar Frontal Zone was displaced northward from the Gulf Stream. Anomalously cold, maritime climatic conditions persisted along the central Atlantic coast, reflecting the position of the cold-marine Labrador Current between the Atlantic Seaboard and the Gulf Stream. During the mid-Holocene, or Hypsithermal, interval, from 8,000 to 4,000 B.P., prevailing westerlies expanded the midcontinental region of warmth and aridity. For the last 4,000 years, the modern climatic regime has been characterized by increased meridional flow.
Plasticization of poly(styrene‐b‐isobutylene‐b‐styrene) ionomers by acid salts of 2‐ethylhexyl‐p‐dimethylaminobenzoate

Poly(styrene-b-isobutylene-b-styrene block copolymer ionomer (overall molecular weight = 71,200 g/mole; 25.5 wt % polystyrene, 4.7% sulfonation of phenyl units, 100% neutralized with KOH) was compounded with various organic and inorganic acid salts of 2-ethylhexyl-p-dimethylaminobenzoate (ODAB) to explore the efficacy of these compounds as ionic plasticizers. Results were compared to the same polymer plasticized by zinc stearate. Plasticizers were added to the polymer at levels of ∼5 wt%. Films were prepared by solution casting from tetrachloroethylene. Thermogravimetric analysis (TGA) showed all ODAB derivatives to have lower decomposition temperatures than zinc stearate. Dynamic mechanical analysis (DMA) of the films showed varying degrees of ionic plasticization as evidenced by a lowering of the temperature at which the onset of flow occurred. With the exception of the stearic acid salt of ODAB, all ODAB derivatives were more efficient ionic plasticizers than zinc stearate. Among the ODAB derivatives, the degree of ionic plasticization varied, with the methane sulfonic and p-toluene sulfonic acid salts being most effective, leading to the conclusion that processing temperatures could be tailored to specific applications by choice of plasticizer and level of incorporation.
Perspectives on Auditing Education after Sarbanes‐Oxley

The events leading up to and culminating in the passage of the Sarbanes‐Oxley Act of 2002 dramatically impacted the auditing profession and auditing practice. Auditing is again the primary revenue source at the major accounting firms and is growing significantly. The auditing environment after passage of the Act demands students with greater understanding of risk assessment, including business and fraud risks, forensic accounting skills, the ability to understand and document controls and link controls to assertions and audit evidence, and the competence to deal with corporate governance and other PCAOB requirements. Acquiring these skills will require changes in the basic auditing course and one or more advanced auditing courses, as well as changes in the core business and accounting curriculum.
Streaming Video: The Collaborative Convergence of Technical Services, Collection Development, and Information Technology in the Academic Library

To meet the rapid evolution of visual media and changing patron expectations, Brigham Young University's Harold B. Lee Library created Byugle, a device to stream videos to their users. This article describes the new challenges streaming video creates for librarians and the cooperative efforts of subject librarians, technical services, and the Information Technology Department as they work together to meet these challenges to provide streaming media for their patrons.
Flip Chip Reliability on Dynamically Loaded Multi-Functional Spacecraft Structures

Electronic packages for space flight are becoming increasingly dense to allow for increased processing power and functionality. This has resulted in further hybridization of electronics where active devices are no longer surrounded by there own case or component package and are directly attached to the substrate. Chip-on-board approaches are being qualified for space flight use with flip chip approaches required to meet smaller volume requirements. These bare die attachment solutions are resulting in electronic sub-systems that have significantly lower weight and volume than state-of-the-art designs. Incorporating electronic traces or signal paths directly into the spacecraft or instrument structure can provide a significant savings in weight and volume. In addition, local computer processing power, increased operational speed and larger memory storage are achievable by using embedded or direct chip attach design methods. Recent developments in printed circuit board fabrication processes has given printed circuit boards increased strength and stiffness by incorporating single or multiple carbon graphite weave layers within the printed circuit board structure during the lamination fabrication process. Previous technology development work has demonstrated the significant mechanical yield strength and stiffness of multifunctional structures when printed circuit boards are laminated with graphite weave made from carbon fiber strands. Standard printed circuit board planar geometries with unique design features are used to construct three dimensional structural elements comprising a subsystem multi-functional structure.
A potent and specific morpholino antisense inhibitor of hepatitis C translation in mice

Hepatitis C virus (HCV) is an RNA virus infecting one in every 40 people worldwide. Current treatments are ineffective and HCV is the leading cause of liver failure leading to transplantation in the United States and Europe. Translational control of HCV is a prime therapeutic target. We assessed the inhibitory potential of morpholino phosphoramidate antisense oligonucleotides (morpholinos) on HCV translation by codelivering them with reporter plasmids expressing firefly luciferase under the translational control of the HCV internal ribosome entry site (IRES) into the livers of mice. Real-time imaging of HCV IRES luciferase reporter messenger RNA (mRNA) translation in living mice showed that a 20-mer complementary to nucleotides 345-365 of the IRES inhibited translation by greater than 95% for at least 6 days and showed mismatch specificity. No significant nonspecific inhibition of a cap-dependent luciferase or encephalomyocarditis virus (EMCV) IRES luciferase reporter translation was observed. Inhibition by the 20-mer morpholino was dose dependent, with 1 nmol/mouse giving the highest inhibition. In conclusion, morpholino antisense oligonucleotides are potent inhibitors of HCV IRES translation in a preclinical mouse model; morpholinos have potential as molecular therapeutics for treating HCV and other viral infections. The in vivo model described is a broadly applicable, straightforward, and rapid readout for inhibitor efficacy. As such, it will greatly facilitate the development of novel therapeutic strategies for viral hepatitis. Notably, the level of antisense inhibition observed in this in vivo model is similar to the maximal inhibition we have obtained previously with RNA interference in mice.
Effects of Kv1.1 channel glycosylation on C-type inactivation and simulated action potentials.

Kv1.1 channels are brain glycoproteins that play an important role in repolarization of action potentials. In previous work, we showed that lack of N-glycosylation, particularly lack of sialylation, of Kv1.1 affected its macroscopic gating properties and slowed activation and C-type inactivation kinetics and produced a depolarized shift in the steady-state activation curve. In our current study, we used single channel analysis to investigate voltage-independent C-type inactivation in both Kv1.1 and Kv1.1N207Q, a glycosylation mutant. Both channels underwent brief and long-lived closures, and the lifetime and frequency of the long-lived closed states were voltage-independent and similar for both channels. We found that, as in macroscopic measurements, Kv1.1N207Q exhibited a ∼8 mV positive shift in its single channel fractional open time (fo) and a shallower fo–voltage slope compared with Kv1.1. Data suggested that C-type inactivation reflected the equilibration time with at least two slow voltage-independent long-lived closed states that followed the rapid activation process. In addition, data simulation indicated that the C-type inactivation process reflected the equilibration time between the open state and at least two long-lived closed states. Moreover, the faster macroscopic current decay in Kv1.1 mostly reflected a slower equilibration time in these channels as compared with Kv1.1N207Q. Finally, action potential simulations indicated that the N207Q mutation broaden the action potential and decreased the interspike interval. The shape of the action potential was not significantly affected by C-type inactivation, however, for a given channel, C-type inactivation increased the interspike interval. Data and simulations suggested that excitable cells could use differences in K+ channel glycosylation degree as an additional mechanism to increase channel functional diversity which could modify cell excitability.
Performance comparison of slow-light coupled-resonator optical gyroscopes

We investigate the connection between group veloc- ity and rotation sensitivity in a number of resonant gyroscope designs. Two key comparisons are made. First, we compare two conventional sensors, namely a resonant fiber optic gyroscope (RFOG) and an interferometric fiber optic gyroscope (FOG). Second, we compare the RFOG to several recently proposed coupled-resonator optical waveguide (CROW) gyroscopes. We show that the relationship between loss and maximum rotation sensitivity is the same for both conventional and CROW gy- roscopes. Thus, coupling multiple resonators together cannot enhance rotation sensitivity. While CROW gyroscopes offer the potential for large group indices, this increase of group index does not provide a corresponding increase in the maximum sen- sitivity to rotation. For a given footprint and a given total loss, the highest sensitivity is shown to be achieved either in a conven- tional RFOG utilizing a single resonator, or a conventional FOG. Unidirectional CROWs: Folded configuration, twisted config- uration and planar configuration with alternating large and small rings.
Flutter Analysis of Flat Rectangular Panels Based on Three-Dimensional Supersonic Potential Flow

Flutter analysis of flat rectangular panels based on three-dimensional supersonic unsteady potential flow
Export of Cadmium and Phytochelatin by the Marine Diatom Thalassiosira weissflogii

Cadmium is one of the most toxic trace metals and induces high concentrations of the metal-binding polypeptide phytochelatin, (γ-Glu-Cys)nGly where n ≥ 2, in the marine diatom Thalassiosira weissflogii. Here we show that at high inorganic cadmium concentrations there is an efflux of cadmium from T. weissflogii so large that over half the cadmium taken up by the cell is returned to the medium. At high inorganic cadmium, there is also an efflux of phytochelatin from the cell. The efflux of both cadmium and phytochelatin stops when the external inorganic cadmium concentration is reduced. The efflux of phytochelatin and cadmium occurs at a molar ratio of approximately 4 γ-Glu-Cys subunits per cadmium, a stoichiometry similar to that measured in vivo for the cadmium−phytochelatin complex. We hypothesize that T. weissflogii exports the phytochelatin− cadmium complex as a detoxification mechanism. The cadmium−phytochelatin complex does not appear to be very stable in seawater once outside the cell since the cadm...
Two-Dimensional Simulations of Wake Vortex Detection Using Radio Acoustic Sounding Systems

Aparallelcodeisdevelopedtosimulatenumericallywakevortexdetectionusingaradioacousticsoundingsystem (RASS). The code is written in FORTRAN 90 with the message passing interface for parallel implementation. The numerical simulation solves simultaneously the linearized Euler equations for a nonuniform mean e ow and the Maxwellequationsforanonhomogeneousmedium.Theradartransmitterandreceiverantennasaremodeledusing an array of point sources and a beam-forming technique, respectively. Many features of the RASS are explored using thenumericalsimulation.First,a uniformmeane owisconsidered,and theRASSsimulation isperformedfor two different types of incident acoustic e eld: a short single-frequency acoustic pulse and a continuous broadband acoustic source. Both monostatic and bistatic cone gurations are examined, and their results are compared. Taylor and Oseen vortex velocity proe les are used as samplemodels, and their mean e owe eldsare reconstructed from the backscattered electromagnetic signal using the Abel transform. The effect of radar beam width is also considered, as are the issues of nonaxisymmetric and interacting vortices. I. Introduction T HEcapacity of airports is constrainedseverelyby the airtrafe c control system’ s consideration of aircraft wake vortices. The present Instrument Flight Rules (IFR) restrictions are based on aircraft weight. The “ 3‐ 4‐ 5‐ 6 rule” sets the separation distances of aircraft by categories from small, less than 41,000 lb (18,600 kg), to heavy, greater than 255,000 lb (116,000 kg). These separations are viewed as very conservative. However, because there remains signie cant uncertainty about wake vortex behavior under different atmospheric conditions, there are considerable technological barriers to improvements in terminal area productivity. In an attempt to enhance airport capacity, an aircraft vortex spacing system (AVOSS) has been under development at NASA Langley Research Center. The AVOSS will provide the means to allow air trafe c control to reduce spacing safely in instrument operations when the appropriate weather conditions exist. A key element in AVOSS is the development of a real-time reliable wake vortex detection system (WVDS). A radio acoustic sounding system (RASS) is a promising candidate for a WVDS. The basic concept of RASS is based on the tracking of sound waves with radar. When acoustic waves are transmitted, they produce pressure perturbations, which lead to e uctuations in the atmospheric permittivity. An incident electromagnetic e eldisthenscatteredduetothepermittivityvariationsandgenerates an echo that can be detected by a receiver antenna. The spectrum of this echo shows a Doppler shift proportional to the local speed of sound. However, the backscattered signals are so weak that no measurable signal would be received unless the Bragg condition is satise ed.The Bragg condition is a relationshipbetween the incident electromagnetic and acoustic wavelengths that ensures a constructive interference between the two waves. The Bragg condition may be written as ¸e D 2¸a sin®
Insulin is a potent survival factor in mesangial cells: role of the PI3-kinase/Akt pathway.

Insulin is a potent survival factor in mesangial cells: Role of the PI3-kinase/Akt pathway. Background Elucidating the mechanisms of apoptosis is important for understanding the molecular mechanisms underlying glomerular disease. The phosphatidylinositol 3 kinase (PI3-kinase)/Akt pathway is essential for survival signaling in non-renal cells. However, little is known about the anti-apoptotic effect of insulin and the role of the PI3-kinase/Akt pathway in mesangial cells (MC) apoptosis. Methods Apoptosis was induced in wild type, p27Kip1 (p27) -/- and p21Cip1/Waf1 (p21) -/- mouse MC by survival factor withdrawal, actinomycin D, ultraviolet (UV)-B irradiation and cycloheximide in the presence or absence of insulin (1 μmol/L) or insulin-like growth factor-I (IGF-I; 100 ng/mL). The activation and levels of Akt, extracellular signal regulated kinase (ERK) and specific cell cycle proteins were determined by Western blot analysis. Results Insulin and IGF-I inhibited wild-type MC apoptosis induced by survival factor withdrawal, actinomycin D, ultraviolet-B irradiation and cycloheximide and in p27 -/- MC when apoptosis was induced by survival factor withdrawal. Akt was activated by insulin and IGF-I during apoptosis. Blocking PI3-kinase with LY294002 reduced Akt activation and abrogated the anti-apoptotic effect of insulin. ERK was activated during apoptosis and blocking ERK activation with U0126 or PD98059 partially rescued MC from apoptosis. Moreover, insulin also suppressed ERK activation during apoptosis. Our results also showed that the CDK-inhibitor p21 was increased by insulin and that p21 up-regulation was PI3-kinase/Akt pathway dependent. Furthermore, p21 -/- MC apoptosis induced by survival factor withdrawal was not rescued by insulin in contrast to the wild-type and p27 -/- MC. These data suggest that p21 may have a critical role in the anti-apoptotic effect of insulin. Conclusions Insulin is a potent survival factor for MC in response to a number of different apoptotic triggers, and this effect is mediated through the PI3-kinase/Akt pathway. Moreover, ERK and p21 may be involved in anti-apoptotic effect of insulin in MC.
Migration of trimethylsilyl groups in enolates of silyl esters

Abstract The lithium enolate of trimethylsilyl acetate ( 1 ) undergoes a 1,3-O → C migration of the trimethylsilyl group.
Aortic Dissections: New Perspectives and Treatment Paradigms

Aortic dissection is a complex manifestation of disease of the arterial wall. The severity and consequences of a dissection are related to the physical characteristics and anatomic location of the tear as well as the underlying patient physiology. Despite in vitro and in vivo modeling advances, our understanding of the pathophysiology has been limited to evaluations of the success and failure of various treatment modalities. The indications for intervention have historically included rupture, intractable pain or hypertension, distal ischemia and degeneration of the aortic wall causing aneurysm formation. The management decisions for patients with dissections are dependent upon the abnormal anatomy, the acuity of the patient presentation, and physiology. Despite the availability of open surgery as a therapeutic option, acute dissections with evidence of ischemia are now handled using an endovascular approach that is specifically directed at the cause of the ischemia. Endovascular treatments include the placement of a stentgraft into the proximal aorta, branch vessel stenting, uncovered stent placement in the abdominal aorta, and aortic fenestrations. Chronic dissections, in contrast, are still most frequently managed with open surgical techniques. However, a subset of patients that are not candidates for traditional surgical repair of the thoracoabdominal aorta may be managed with a combined open mesenteric revascularization with subsequent endovascular grafting of the thoracoabdominal aorta.
Customers helping customers: payoffs for linking customers

Purpose – This paper aims to examine the relationship between customer networks and intercustomer social support, through the theoretical lens of service dominant logic (SDL). Co-creation and objective performance objectives are analyzed to understand the differential impact of instrumental and social/emotional intercustomer support on performance. Design/methodology/approach – A combination of survey and secondary data were collected within a health-club setting to test hypotheses. The data were analyzed using structural equation modeling. Findings – A customer’s network ties positively impact his/her intercustomer support perceptions, and this relationship is moderated by tie strength. Further, instrumental support impacts objective performance measures, while social/emotional has a greater impact on affective outcomes. Research limitations/implications – As customers become more connected, it is in the interest of the organization to capitalize on these connections. Future research should investigate w...
On the hatta normality condition and tax reforms

Abstract The role of the Hatta normality condition in the tax reform literature is discussed. It is shown that, in a one-consumer economy, the Hatta normality condition only pertains to the directions of welfare improving tax reforms, but has no role in determining the existence of such reforms. In a many consumer economy, the Hatta normality condition is shown to affect both the existence and directions of strict Pareto improving tax reforms. It is also shown that the Hatta normality condition can be used to indicate optimality or suboptimality of the economy's initial choice of lump-sum transfers.
Synthesis of Conductive Elastomeric Foams by an In Situ Polymerization of Pyrrole Using Supercritical Carbon Dioxide and Ethanol Cosolvents

Abstract Electrically conductive polyurethane (PU) foams were prepared by first impregnating a PU foam with ferric trifluoromethane sulfonate (ferric triflate) using supercritical carbon dioxide (scCO 2 ) containing 0.2–1.3 vol.% ethanol as a cosolvent, and then exposing the foam to pyrrole vapor. Polypyrrole (PPy) was formed in situ by an chemical oxidative polymerization. The conductivity of the composite foams ranged from 10 −7 to 10 −2 S/cm, depending on the amount of ethanol and impregnation time used. The amount of PPy produced depended on the amount of oxidant absorbed by the foam. For low ethanol concentrations and/or short impregnation time, the PPy produced was concentrated at or near the surfaces of the foam sample. The dispersion of the PPy in the foam was improved by increasing the amount of ethanol and the impregnation time. Ferric trifluoroacetate was more soluble in the scCO 2 /ethanol solutions, but produced foams with much lower conductivity than did ferric triflate.
FEATURED ARTICLE: CONVENIENTLY BLACK: Self-Delusion and the Racial Exploitation of African America

Commentary on the Following PublicationsMcWhorter, John H., Losing the Race: Self-Sabotage in Black America. New York: Free Press, 2000, 285 pages, ISBN 0 684 83669 6, $24.00.McWhorter, John H., Authentically Black: Essays for the Black Silent Majority. New York: Gotham Books, 2003, 264 pages, ISBN 1 59240 001 9, $25.00.
‘This is our speech’: voice, body and poetic form in recent South African writing

In recent years, different South African literary genres have revealed writers’ innovative efforts to name subjectivities and experiences that have been erased by legacies of colonial and sexual violence. By analysing the poem ‘Tongues of Their Mothers’, the novel Unconfessed and the play Reclaiming the P…Word, this essay traces a shift away from realistic representations of the physical and symbolic violence to which Black women’s bodies have been and continue to be subjected. Arguing that an emphasis on violence can unwittingly re-inscribe invasive acts and representations, this article shows how poetic strategies and registers can be used to write Black women’s bodies into alternative modes of visibility. Through a complex interplay of silence and reclamation, the texts unflinchingly confront the legacies, meanings and forms of sexual violence in South Africa, while also conveying new understandings of their histories and the languages that support them. Poetic language provides a powerful means of nam...
Ionic conduction in the Gd2Ti2O7−Gd2Zr2O7 system

Electrical conductivity measurements were made on Gd 2 (Zr 0.3 Ti 0.7 ) 2 O 7 as a function of temperature, oxygen fugacity and aliovalent dopant concentration using Ca and Ta. The oxygen ion conductivity was found to be dominated by oxygen vacancies generated both by intrinsic Frenkel formation and by impurity charge compensation. The Frenkel constant and oxygen vacancy mobility for Gd 2 (Zr 0.3 Ti 0.7 ) 2 O 7 were derived for the first time.
The Dynamin pH Domain Variable Loop 1 (Vl1) is an Assembly-Independent Sensor of Membrane Curvature

The role of the membrane-inserting pleckstrin homology (PH) domain variable loop 1 (VL1) in dynamin-catalyzed membrane fission remains unclear. A membrane bending function has been proposed based on the bilayer-couple mechanism and the inability of a membrane insertion-defective VL1 point mutant (Dyn1 I533A) to generate curvature from model membrane templates in vitro. Here using site-directed fluorescence labeling coupled to multiple, independent spectroscopic techniques and confocal imaging on Giant Unilamellar Vesicles (GUVs), we have resolved the role of VL1 in dynamin function. Contrary to current understanding, our characterization of the isolated Dyn1 PH domain in comparison to full-length dynamin reveals that the PH domain VL1 is primarily a sensor of membrane curvature that serves in partitioning dynamin to regions of high membrane curvature (i.e. the narrow membrane neck of an invaginated coated pit) in order to direct localized dynamin self-assembly. Similar to full-length dynamin, the isolated PH domain preferentially inserted into highly curved membrane bilayers. However, unlike the full-length molecule, the PH domain was unable to generate curvature from planar membrane templates on its own. Our studies further reveal that in vivo fission-incompetent Dyn1 I533A fails to distinguish membrane curvature in vitro and is defective in directing organized self-assembly on curved membrane templates. Our studies provide critical insights into the role of the PH domain VL1 in dynamin function and expand the repertoire of PH domain functionality in protein-protein and protein-membrane interactions.
Attending to Threat: Race-based Patterns of Selective Attention

The present research investigated the extent to which the stereotype that young Black men are threatening and dangerous has become so robust and ingrained in the collective American unconscious that Black men now capture attention, much like evolved threats such as spiders and snakes. Specifically, using a dot-probe detection paradigm, White participants revealed biased attention toward Black faces relative to White faces (Study 1). Because the faces were presented only briefly (30-ms), the bias is thought to reflect the early engagement of attention. The attentional bias was eliminated, however, when the faces displayed averted eye-gaze (Study 2). That is, when the threat communicated by the Black faces was attenuated by a relevant, competing socio-emotional cue—in this case, averted eye-gaze—they no longer captured perceivers’ attention. Broader implications for social cognition, as well as public policies that reify these prevailing perceptions of young Black men are discussed.
An operational view of the role of health librarians in informatics

The National Library of Medicine is currently funding the Pilot Connections project to promote and support use of the INTERNET in community health care settings. With previous networking applications of this kind largely confined to academic and research environments, the health librarian has emerged as the agent with the unique knowledge and skills to participate in and manage organizational change. An experiment in applied informatics, the Pilot Connections project shows how health librarians should be aware of the expanding opportunities that exist for them to help their organizations cope more effectively with the external trends and forces currently affecting the role and value of information.
Future IS research in net-enabled organizations

This essay explores the interplay of network technology and the stakeholder viewpoint to argue that the information systems (IS) discipline is now in its third era of networking, and rapidly moving toward a fourth era. The first era, sans significant networks, concentrated on increasing employee productivity. The introduction of private networks ushered in a second era and brought in interorganizational systems that permitted interaction between and among businesses and governments. The third era is built on public networks, which enable firms to interact electronically with individual customers and investors, and to interact in new ways with governments. The fourth era, yet to arrive, will be built on high functionality, mobile devices that support real-time access and stakeholder locatability. Each era results in an order of magnitude increase in the potential impact of information systems on organizational performance because it can address the objectives of one or more additional groups of stakeholders.Net-enabled organizations (NEOs) are the key evolutionary development of the third era. These organizations require insights into how to organize, architect, and implement the entire range of their electronic connections in the next several decades, and IS researchers are uniquely positioned to deliver on this vision.