cssi/SciSciGPT-SciSciNet huggingface dataset:
The significance of the phi rhythm

We reviewed two series of patients with the phi rhythm (posterior rhythmic slow waves occurring after eye closure) to determine its characteristics and clinical significance. Phi rhythm was defined as a minimum of three consecutive monomorphic posterior delta waves occurring within 2 sec of eye closure on at least two occasions during electroencephalography. Group 1 consisted of 30 patients (16 male and 14 female) with a mean age of 11.6 +/- 8.4 years (range, 3 to 46 years) who were evaluated between 1978 and 1993. Phi rhythm most commonly occurred when the patient was alert and after concentrated visual attention, such as reading or picture or pattern scanning. Seventeen of these patients had epilepsy (11 generalized, 3 focal, 1 both, and 2 unclassified). The frequency of epilepsy was not significantly different from that of a control group of 60 patients matched for age and sex; however, generalized epilepsies were more common in the phi group (P = 0.008). Group 2 consisted of a previously unreported series of 121 patients evaluated between 1960 and 1962. A diverse range of underlying clinical diagnoses was evident in both groups. The mechanism of the phi rhythm is unknown, but the findings suggest that the origin is subcortical and that the presence of this activity should not be considered diagnostic of a seizure disorder.
Cystatin S: Molecular biology and sympathetic innervation

The ratsubmandibular glands (SMG) are innervated by both the sympathetic and the parasympathetic branches of the autonomic nervous system which, in turn, regulate the secretory functions of the glands. Parasympathetic innervation of rat SMG is present at birth, whereas sympathetic nerve fibers reach the glands by postnatal day 5. Isoproterenol (IPR), a β-adrenoceptor agonist, induces hypertrophic and hyperplastic enlargements of rat salivary glands, and induces the expression of a number of genes, including cystatin S, a member of family 2 of the cysteine proteinase inhibitor superfamily. Cystatin S gene expression is tissue- and cell type-specific, occurs transiently during development, and is not observed in adult animals. Sympathetic denervation of adult SMG, achieved by removing the superior cervical ganglion, reduces the induction of the cystatin S gene by a single injection of IPR. In addition, recent data indicate that the β-receptors present early in the developing SMG are functional and are capable of responding to IPR by increasing the expression of the cystatin S gene, even when sympathetic nerve fibers have not reached the gland. The level of IPR-induced cystatin S mRNA remains constant until day 8, at which time a dramatic induction of cystatin S mRNA is observed. This statistically significant increase in cystatin S mRNA at day 8 was diminished, but not completely suppressed, upon sympathectomy of one day old animals. These data indicate that an intact sympathetic innervation is not requisite for induction of cystatin S gene expression by IPR in developing SMG. However, sympathetic innervation is required for the full IPR response of the cystatin S gene in these glands. Collectively, these experiments suggest that factor(s) derived from the sympathetic nervous system participate in IPR-induced expression of the cystatin S gene in the rat SMG. Biomedical Reviews 1998; 9: 33-46.
Neuroprotective Action of Halogenated Derivatives of L-Phenylalanine

Background and Purpose— The aromatic amino acid L-Phenylalanine (L-Phe) significantly and reversibly depresses excitatory glutamatergic synaptic transmission (GST) via a unique set of presynaptic and postsynaptic mechanisms. Therefore, we hypothesized that endogenous derivatives of L-Phe, which display potent antiglutamatergic activity, may safely and efficaciously protect the brain during conditions characterized by overactivation of glutamate receptors. Methods— We tested this hypothesis in vitro with a combination of patch-clamp and lactate dehydrogenase (LDH) analyses in rat cultured neurons exposed to simulated ischemia, and in vivo using a rat model of experimental stroke caused by transient middle cerebral artery occlusion (MCAO). Results— 3,5-diiodo-l-tyrosine (DIT) and 3,5-dibromo-l-tyrosine (DBrT), endogenous halogenated derivatives of L-Phe, attenuated GST by similar mechanisms as L-Phe, but with greater potency. For example, the IC50s for DIT and DBrT to depress the frequency of alpha-amino-3-...
Disjunctive concept identification: Stimulus complexity and positive versus negative instances

Eighty college students served in a disjunctive concept task, 20 in each of four conditions which differed in stimulus complexity (high vs. low) and type of instances the S received (positive vs. negative). Each S received 20 concept problems followed by five additional problems on which they received the opposite type of instances. Contrary to expected results, the negative instance groups were initially superior. An interaction of type of instances with complexity was found on later trials.
WE‐E‐224A‐04: Potential and Challenges of Integrated Brachytherapy‐IMRT Planning

Combinations of external‐beam radiation therapy (EB) and brachytherapy (BT) and have been used for many years. Conventionally, the EB and BT components are planned independently and limited to combinations of doses and dose‐time‐fractionation patterns that have been directly validated by clinical outcome studies. Ongoing research in radiobiological modeling, deformable image registration, and quantification of dose delivery uncertainties has the potential to provide the scientific foundation for truly integrated EB‐BT planning that could significantly improve clinical outcomes. First, the complementary strengths and weaknesses of BT and highly conformal EB methods, such as intensity‐modulated radiation therapy(IMRT), will be reviewed. Both IMRT and BT can support high dose conformality. IMRT can treat large surgically inaccessible target volumes with relatively homogeneous dose distributions. Where BT can be surgically realized, large dose fractions can be delivered with much higher geometric precision than with current IMRT delivery techniques. Next, clinical settings where integrated BT‐IMRT can have benefit will be reviewed. One example is definitive treatment of cervical cancer in which IMRT is used to compensate for primary tumor underdosing or normal tissue overdosing by the intracavitary BT insertions as well as for conformal treatment of the pelvic lymph nodes. Finally, the scientific and clinical challenges to integrated BT‐IMRT will be reviewed. For example, in high dose‐rate (HDR) interstitial BT of the prostate combined with IMRT whole pelvic irradiation for intermediate risk disease, a major source of dose‐delivery uncertainty is the conversion from physical‐to‐isoeffective dose needed to account for differences in fractionation.
Enhancing Older Adults' Reading Comprehension.

Syntactic measures, as well as measures of sentence content, were used with hierarchical multiple regression techniques to investigate older adults’ reading comprehension. Older adults’ reading difficulty, as measured by a test of comprehension and words‐per‐minute reading rates, appears to be due to the use of propositionally dense sentences and complex syntactic structures. This analysis provides clear guidelines for the preparation of prose materials targeted for older readers.
Community-Based Participatory Clinical Research in Obesity by Adolescents: Pipeline for Researchers of the Future

We propose a novel, untapped opportunity, challenging cultural and man-power barriers to transferring advances in biomedical science knowledge that will improve community health care (Type II Clinical Translational Research) in a medically underserved community. We describe a pilot model in which adolescents apply principles of Community-Based Participatory Research (CBPR) at the epicenter of the obesity diabetes epidemic in rural Appalachia in West Virginia. The model invites minority, financially disadvantaged, and educationally disadvantaged adolescents to become educated on ethics, then provides infrastructure to support study design and conduct of CBPR. This experience demonstrates that these adolescents can effi ciently, with quality and integrity, reach into the most vulnerable of communities and their own families to show that the prevalence of obesity is at 50% and diabetes 10.4% (n= 989). Our experience illustrates the infrastructure requirements for this strategy to be successful and emphasizes the substantial benefit that could accrue if the model is successfully sustained. The benefit includes not only the translation of knowledge to influence community lifestyle behavior but also the creation of a pipeline of new biomedical scientists for the future.
Axisymmetric stresses in transversely isotropic finite cylinders

Abstract The elastostatic analysis of transversely isotropic finite cylinders with stress-free lateral surfaces is considered using the formulation in terms of a displacement potential. Solution in the form of the eigenfunction expansion where each of the eigen-functions satisfies the lateral boundary conditions is obtained. The end conditions are satisfied by means of the general orthogonality relations for the radial eigenfunctions. The orthogonality technique gives closed-form expressions for the Fourier-Bessel coefficients for certain types of mixed end conditions. For other cases the technique leads to an infinite set of linear equations. The convergence of these equations are examined and solutions are obtained by suitable truncation. Both stress and displacement end conditions are considered and numerical results for two types of transversely isotropic materials are presented.
Multiple potential regulatory elements in the 5' flanking region of the beta 3-adrenergic receptor.

Since the promoter regions of several genes which modulate intracellular cAMP contain cAMP responsive elements which participate in the regulation of transcription, we assessed whether similar elements were present in the 5′ flanking region of the recently cloned human β-adrenergic receptor. This receptor is coupled to cAMP formation, and may play a key role in adrenergic receptor-mediated lipolysis and thermogenesis. Therefore, from a human genomic library we cloned the β3-AR coding block and a 1,320 base pair region immediately 5′ upstream from the initiation of translation. Based on the classic consensus sequence, we found four potential cAMP responsive elements in this 5′ flanking region: CGAGGTCA, TCACATCA, TGAGGTCT and TGACTCCA.
Patch-wise Ideal Stopping Time for Anisotropic Diffusion

Data-dependent filtering methods are powerful techniques for image denoising. Beginning with any base procedure (nonlinear filter), repeated applications of the same process can be interpreted as a discrete version of anisotropic diffusion. As such, a natural question is "What is the best stopping time in iterative data-dependent filtering?" This is the general question we address in this paper. To develop our new method, we estimate the mean-squared-error (MSE) in each image patch. This estimate is used to characterize the effectiveness of the iterative filtering process, and its minimization yields the ideal stopping time for the diffusion process.
Robust weighted gain-scheduling H ∞ vehicle lateral dynamics control in the presence of steering system backlash-type hysteresis

A robust weighted gain-scheduling H∞ controller for lateral motion control of in-wheel-motor-driven electric vehicles is presented in this paper. The main control objective is to track the reference yaw rate and regulate the vehicle lateral velocity, with the steering angle and the external yaw moment as two inputs. Two major challenges are dealt with. First, the backlash-type hysteresis embedded in the steering system of a ground vehicle adds a disturbance term to the system. Second, the vehicle longitudinal velocity and the tire cornering stiffness are considered variable, thus making the vehicle lateral dynamics model a linear time-varying uncertain system. The state feedback gain matrix of the controller is designed in the envelope of the weighted H∞ performance, and solved using a linear matrix inequality tool. The relative importance of the tracking error and the steering hysteresis can be tuned by a weighting factor; and the uncertainties in the system matrices are resolved by a gain-scheduling design. In addition, the physical limitations of the actuators are treated by an eigenvalue placement technique. Simulation studies conducted in CarSim® show that the proposed controller is capable of attenuating the effects of both the steering system nonlinearities and the time-varying parameters.
Preliminary design of a meteoroid/orbital debris shield system for a Mars mission spacecraft

A preliminary design of a spacecraft shield system to defeat meteoroids and orbital debris during a Mars mission is presented. The mission scenario is first defined in terms of stage times which include LEO, transit, low-Mars orbit, and Mars surface periods. The environment definitions for earth-orbital space debris, planetary meteoroids, and interplanetary meteoroids are next introduced. Shield system design approaches incorporate stochastic simulation, hydrocode analyses, hypervelocity impact testing, and optimization techniques. Structural design trades presented include spacecraft configuration, mission schedule, penetration risk, and total standoff distance between the bumper and wall.
Estimating Bounds on Fracture Stresses Determined from Mirror Size Measurements

Statistical techniques are used to derive closed-form, approximate solutions for estimating a standard deviation on the fracture stress determined from mirror size measurements. The estimated coefficient of variation of fracture stress is noted to be twice as sensitive to the variation of the mirror constant, Aj, as to the variation in the measured boundary radius, r j . This allows the hackle radius to be reasonably estimated and bounded from the mirror and branch radii when it cannot be clearly delineated.
ANALYTICAL RESOLUTION OF THE CRYSTALLINE SAND PYRAMIDS

Pyramid-shaped crystals of calcium oxalate comprise the "crystal sand" found in certain flowering plants. They have presented an enigma to both botanists and crystallographers since their description nearly a century ago. Even though it is impossible to build a tetrahedron from the atomic lattice cell units of the mineral, the four-sided crystals are found within vacuoles of plant cells. Scanning electron microscopy, acid-etching procedures, x-ray analysis, and the results of synthetic in vitro crystal-growth experiments were used to resolve the problem. Individual crystals of crystal sand are shown to be twin and triplet crystals. A newly presented Stability Determination Procedure distinguishes the hydration forms of phytocrystalline calcium oxalate by their stability in oxalic acid. It shows crystal sand to be calcium oxalate monohydrate. Based on information from plant crystal sand, a new twofold rotational twin axis is proposed for the mineral whewellite.
Ionic mobility dispersion in KCD digital radiography: dopants and physical parameters

The spatial resolution of the Kinestatic Charge Detector (KCD) for digital radiography is limited by mobility dispersion when the detector operates with noble gases such as xenon or krypton. The magnitude and dependence on drift distance of the peak widths of ionic signal pulses produced in the KCD provide a measure of mobility dispersion. These parameters have been measured in a KCD filled with krypton gas at a pressure of 60 atm, and in the same gas alternately doped with 1.7% of each of the following amine additives: ammonia, methylamine, dimethylamine and trimethylamine. The ionization potentials of these dopants are 10.2, 9.0, 8.2 and 7.8 ev, respectively. While the undoped medium exhibited significant mobility dispersion, all four of the amine-doped media showed dramatic reduction or elimination of mobility dispersion.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Packed capillary column solvating gas chromatography using mobile phases that transition from liquid to gas between the column inlet and outlet

In this study, organic solvents at temperatures higher than their normal boiling points were used as mobile phases for packed capillary column chromatography. No restrictor or back pressure was imposed on the column outlet. As a result, a large difference in mobile-phase properties existed, and a phase transformation from liquid to gas occurred, along the column. Solvating gas chromatography (SGC) was used to characterize this chromatographic process because, near the column outlet, a gaseous mobile phase existed. Chromatographic performance characteristics including mobile-phase flow, column efficiency, mobile-phase solvating power, and solute retention were investigated using fused-silica capillary columns packed with microparticles (5- and 10-μm diameters). It was found that when the temperature was increased to values that were higher than the normal mobile-phase boiling point, the mobile-phase linear velocity increased rapidly at constant column inlet pressure. Although large differences in mobile-ph...
Effects of drugs on nutrition.

Abstract Drugs can increase nutrient requirements through various mechanisms and if these requirements are not met by dietary modification or provision of nutrient supplements, deficiency disease will result. Commoner nutritional effects of drugs consist in the insidious development of hypovitaminoses; other serious nutritional consequences of drug intake include growth impairment and, in the case of vitamin antagonists, poisoning through interference with metabolic processes dependent on the activity of vitamins or coenzymes. Interactions may exist between pharmacologic agents and nutrients with respect to their absorption, transport, metabolism and excretion. Single drugs can cause nutrient depletion by more than one mechanism and multiple drug regimens can deplete nutrient stores by a synergistic effect. Risks of drug-induced malnutrition with drugs increase with dose and duration of intake, marginal diets and co-existence of disease which increases requirements for the same nutrients that are affected by the drug.
Assessment of the depth-dependence of the mechanical parameters of a layered medium using surface excitation and motion measurements on the surface

In this study the dynamic behavior of a layered viscoelastic medium in response to the impulsive acoustic radiation force applied to its surface was investigated. To verify our theoretical model, experiments were performed using tissue-like gel-based phantoms of varying mechanical properties. A 3.5 MHz single-element focused transducer was used to apply the radiation force at the surface of the phantoms and a phase-sensitive OCT system was used to track the displacements on the phantom surface. The results of this study demonstrate good agreement between theoretical predictions and experimental measurements. It was demonstrated that layers at different depths introduce responses at different frequencies. Therefore, the proposed model in combination with spectral analysis can be used to evaluate depth dependant distribution of the mechanical properties based the measurements on the tissue surface.
A Misexpression Screen Reveals Effects of bag-of-marbles and TGFβ Class Signaling on the Drosophila Male Germ-Line Stem Cell Lineage

Male gametes are produced throughout reproductive life by a classic stem cell mechanism. However, little is known about the molecular mechanisms for lineage production that maintain male germ-line stem cell (GSC) populations, regulate mitotic amplification divisions, and ensure germ cell differentiation. Here we utilize the Drosophila system to identify genes that cause defects in the male GSC lineage when forcibly expressed. We conducted a gain-of-function screen using a collection of 2050 EP lines and found 55 EP lines that caused defects at early stages of spermatogenesis upon forced expression either in germ cells or in surrounding somatic support cells. Most strikingly, our analysis of forced expression indicated that repression of bag-of-marbles (bam) expression in male GSC is important for male GSC survival, while activity of the TGF beta signal transduction pathway may play a permissive role in maintenance of GSCs in Drosophila testes. In addition, forced activation of the TGF beta signal transduction pathway in germ cells inhibits the transition from the spermatogonial mitotic amplification program to spermatocyte differentiation.
Transcription factor TFIIIB and transcription by RNA polymerase III.

pol (RNA polymerase) III is charged with the task of transcribing nuclear genes encoding diverse small structural and catalytic RNAs. We present a brief review of the current understanding of several aspects of the pol III transcription apparatus. The focus is on yeast and, more specifically, on Saccharomyces cerevisiae ; preponderant attention is given to the TFs (transcription initiation factors) and especially to TFIIIB, which is the core pol III initiation factor by virtue of its role in recruiting pol III to the transcriptional start site and its essential roles in forming the transcription-ready open promoter complex. Certain relatively recent developments are also selected for brief comment: (i) the genome-wide analysis of occupancy of pol III-transcribed genes (and other loci) by the transcription apparatus and the location of pol III transcription in the cell; (ii) progress toward a mechanistic and molecular understanding of the regulation of transcription by pol III in yeast; and (iii) recent experiments identifying a high mobility group protein as a fidelity factor that assures selection of the precise transcriptional start site at certain pol III promoters.
Calcium channel current in rat dental pulp cells.

Voltage-gated Ca2+ currents in early-passage rat dental pulp cells were studied using whole-cell patch-clamp techniques. With Ba2+ as the charge carrier, two prominent inwardly-directed currents, If and Is, were identified in these cells that could be distinguished on the basis of both kinetics and pharmacology. If was activated by membrane depolarizations more positive than −30 mV, and displayed fast inactivation kinetics, while Is was activated by steeper depolarizations and inactivated more slowly. At peak current, time constants of inactivation for If and Is were ∼17 vs.∼631 msec. Both If and Is could be blocked by lanthanum. By contrast, only Is was sensitive to either Bay-K or nifedipine, a specific agonist and antagonist, respectively, of L-type Ca2+ channels. Is was also blocked by the peptide omega-Conotoxin GVIA. Taken together, results suggested that If was mediated by divalent cation flow through voltage-gated T-type Ca2+ channels, whereas Is was mediated by L- and N-type Ca2+ channels in the pulp cell membrane. The expression of these prominent, voltage-gated Ca2+ channels in a presumptive mineral-inductive phenotype suggests a functional significance vis a vis differentiation of dental pulp cells for the expression and secretion of matrix proteins, and/or formation of reparative dentin itself.
Magnetic reconnection and mass acceleration in flare-coronal mass ejection events

An observational relationship has been well established among magnetic reconnection, high-energy flare emissions and the rising motion of erupting flux ropes. In this paper, we verify that the rate of magnetic reconnection in the low corona is temporally correlated with the evolution of flare nonthermal emissions in hard X-rays and microwaves, all reaching their peak values during the rising phase of the soft X-ray emission. In addition, however, our new observations reveal a temporal correlation between the magnetic reconnection rate and the directly observed acceleration of the accompanying coronal mass ejection (CME) and filament in the low corona, thus establishing a correlation with the rising flux rope. These results are obtained by examining two well-observed two-ribbon flare events, for which we have good measurements of the rise motion of filament eruption and CMEs associated with the flares. By measuring the magnetic flux swept through by flare ribbons as they separate in the lower atmosphere, we infer the magnetic reconnection rate in terms of the reconnection electric field Erec inside the reconnecting current sheet (RCS) and the rate of magnetic flux convected into the diffusion region. For the X1.6 flare event, the inferred Erec is ~5.8 V cm-1 and the peak mass acceleration is ~3 km s-2, while for the M1.0 flare event Erec is ~0.5 V cm-1 and the peak mass acceleration is 0.2-0.4 km s-2.
Intensity-adaptive segmentation of single-echo T1-weighted magnetic resonance images.

A procedure for segmentation of intracranial tissues, including cerebrospinal fluid surrounding the brain, cortical and subcortical gray matter, and white matter, in a T1-weighted magnetic resonance image of the brain, has been developed. The proposed method utilizes information from the histogram of pixel intensities of the intracranial image. Based on this information, an unsupervised K-means clustering procedure separates various tissue regions. Information about the approximate location of anatomical regions within the intracranial space is used to detect ventricles and the caudate nuclei. First a description and justification for the procedure is presented. Then the performance of the procedure is evaluated by analysis of variance. In conclusion, the results of applying this procedure to 31 healthy subjects are presented and future improvements are discussed. Hum. Brain Mapping 5:194–205, 1997. © 1997 Wiley-Liss, Inc.
Three-dimensional diffuse optical mammography with ultrasound localization in a human subject

We describe an approach that combines clinical ultrasound and photon migration techniques to enhance the sensitivity and information content of diffuse optical tomography. Measurements were performed on a postmenopausal woman with a single 1.8 x 0.9 cm malignant ductal carcinoma in situ approximately 7.4 mm beneath the skin surface (UCI IRB protocol 95-563). The ultrasound-derived information about tumor geometry enabled us to segment the breast tissue into tumor and background regions. Optical data was obtained with a multifrequency, multiwavelength hand-held frequency-domain photon migration backscattering probe. The optical properties of the tumor and background were then computed using the ultrasound-derived geometrical constraints. An iterative perturbative approach, using parallel processing, provided quantitative information about scattering and absorption simultaneously with the ability to incorporate and resolve complex boundary conditions and geometries. A three to four fold increase in the tumor absorption coefficient and nearly 50% reduction in scattering coefficient relative to background was observed (lambda = 674, 782, 803, and 849 nm). Calculations of the mean physiological parameters reveal fourfold greater tumor total hemoglobin concentration [Hbtot] than normal breast (67 microM vs 16 microM) and tumor hemoglobin oxygen saturation (SOx) values of 63% (vs 73% and 68% in the region surrounding the tumor and the opposite normal tissue, respectively). Comparison of semi-infinite to heterogeneous models shows superior tumor/background contrast for the latter in both absorption and scattering. Sensitivity studies assessing the impact of tumor size and refractive index assumptions, as well as scan direction, demonstrate modest effects on recovered properties.
Xe Operation with the Nonambipolar Electron Source

A radio frequency (RF) plasma-based electron source that does not rely on electron emission at a cathode has been constructed and is able to produce 30 A of electron current when using 2.2 seem Xe, 1200 W RF power at 13.56 MHz. All of the random electron flux in the device is extracted through an electron sheath resulting in total non-ambipolar flow. The non-ambipolar electron source (NES) has an axial expanding magnetic field of 100 gauss that results in a uniform plasma potential across a 1 cm diameter aperture allowing for uniform electron extraction without the need for extraction grids. The applied magnetic field also allows for the operation in a helicon mode. The electron current extracted from NES is 300 times greater than the Bohm current that could be extracted through the same aperture. NES has comparable current densities, superior neutral gas utilization, and the promise of longer operational lifetimes than conventional electron sources such as hollow cathodes, where the operational lifetime in such devices is ultimately limited bv cathode deterioration.
A Galerkin implementation of the generalized Helmholtz decomposition of vorticity formulations

Abstract Vorticity formulations for the incompressible Navier–Stokes equations have certain advantages over primitive-variable formulations including the fact that the number of equations to be solved is reduced. However, the accurate implementation of the boundary conditions seems to continue to be an impediment to the acceptance and use of numerical methods based on vorticity formulations. Velocity boundary conditions can be implicitly satisfied by maintaining the kinematic compatibility of the velocity and vorticity fields as described by the generalized Helmholtz decomposition (GHD). This can be accomplished in one of two ways by either solving for boundary vorticity (leading to a Dirichlet boundary condition for the vorticity equation) or solving for boundary vortex sheet strengths (leading to a Neumann condition). In the past, vortex sheet strengths have often been determined by solving an over-specified set of linear equations. The over-specification arose because integral constraints were imposed on the vortex sheet strengths. These integral constraints are not necessary and typically are included to mitigate errors in determining the vortex sheet strengths themselves. Further, the constraints overspecify the linear system requiring least-squares solution techniques. To more accurately satisfy both components of the velocity boundary conditions, a Galerkin formulation is applied to the generalized Helmholtz decomposition. This formulation implicitly satisfies an integral constraint that is more general than many of the integral constraints that have been explicitly imposed. Two implementations of the Galerkin GHD are considered in the current work, one based on determining the boundary vorticity and one based on determining the boundary vortex sheet strengths. A finite element method (FEM) is implemented to solve the vorticity equation along with the boundary data generated from the GHD.
Gestural coordination of the velum in singing can be different from coordination in speech

Professional singers are trained to maximize vowel duration and minimize consonant interference, while still maintaining intelligibility. The mechanisms by which they do this, however, are unclear. A deeper understanding of the gestural mechanisms utilized during professional-quality singing could be useful to train singers more effectively. It has been well-established that nasal sounds in syllable coda position have longer and larger velum motion in formal speech as compared to casual speech. The hypothesis of this study was that coda velum gestures would be temporally extended proportional to the duration of the entire syllable. To test this, real-time magnetic resonance (rtMR) images of trained soprano singers were used to track the motion of the velum. The boundaries of the vocal tract were mapped to a semi-polar grid, and the velocity of the velum at every frame of its movement was calculated. An important result shows that operatic singing has minimal change in velum gesture duration compared to speech, while a musical theater style can have velum lowering for the duration of a word. Observed gestural kinematics and their implications for speech are discussed from within the framework and perspective of Articulatory Phonology.
Angiogenesis inhibition: A review

Abstract In this review we discuss the concept of anti-angiogenesis, which is the inhibition of neovascularization. Anti-angiogenic agents are viewed from the standpoint of their effect on various elements of the angiogenic process, including induction of vascular discontinuity, endothelial cell movement, endothelial cell proliferation, and three-dimensional restructing of patent vessels. An effort is made to place the many different approaches to anti-angiogenesis research into a comprehensible structure, in order to identify problems of evaluation and interpretation, thereby providing a clearer basis for determining promising and needed directions for further investigation.
K X-ray yields associated with the superdeformed band of 192Hg

Abstract The K X-ray yields associated with the superdeformed band in 192 Hg have been measured. The measured value is compared with that expected from the K-conversion of known discrete lines in the band and of transitions following the deexcitation into the yrast states. The difference between the values allows one time to set limits on the number and multipolarity of unobserved linking transitions. The possibility of strong EO decay out of the superdeformed band is ruled out.
Conceptual problems in noble gas and fluorine chemistry, VI:1 Anomalous reactions of the isoelectronic F2O and Cl2O with lewis acids

Abstract The isoelectronic F 2 O and Cl 2 O are known to react with Lewis acids to produce salts of the unrelated O 2 + and ClO 2 + ions. We propose a unifying mechanism entailing formation of F 3 O 2 + and Cl 3 O 2 + by the simultaneous abstraction of halide ions and attack of a second molecule of the halogen oxide. Logic is presented for nonisostructural arrangements of these ions, F 2 O + -OF and (ClOClOCl) + . Subsequent dehalogenation reactions then produce the observed ions.
Infinite Prandtl number variable viscosity free convection with suction

Abstract The equations describing variable viscosity infinite Prandtl number free convection from a vertical surface with suction were solved using the local nonsimilarity technique. Two heat transfer regimes are recognized: at low values of suction, variable viscosity dominates and can substantially reduce the heat transfer, at moderate to high suction the temperature dependent viscosity plays no role in the description of the heat transfer. Vertical velocities are reduced in magnitude and shifted away from the boundary as the temperature dependence of viscosity is increased.
The impact of magnesium sulfate therapy on angiogenic factors in preeclampsia

Objective The objective was to evaluate whether intravenous magnesium sulfate (magnesium) alters levels of angiogenic factors in women with preeclampsia.
Organizational citizenship behavior and performance evaluations: exploring the impact of task interdependence

The influence of task interdependence on the importance attributed to organizational citizenship behavior (OCB) in evaluations of employee performance was investigated in 3 studies. In Study 1,238 undergraduates were exposed to a task interdependence manipulation and a unit-level performance manipulation and provided citizenship ratings. In Study 2,148 master of business administration students were exposed to a task interdependence manipulation and then rated the importance of OCB in their evaluations of employee performance. In Study 3,130 managers rated the task interdependence in their unit of principal responsibility and the importance of OCB in their overall evaluations of employee performance. The results suggest task interdependence may affect the importance attributed to OCB by evaluators. Implications of these results are explored.
Conflict, Participative Decision‐Making, and Generational Ownership Dispersion: A Multilevel Analysis*

This study examines how participative decision‐making and generational ownership dispersion affect conflict in a sample of privately held U.S. family firms. Our study utilizes a hierarchical linear...
THERMAL CONDUCTIVITY OF ELECTRON-IRRADIATED GERMANIUM

Measurements of the change in low-temperature thermal conductivity of high-purity single-crystal Ge were made upon 2-MeV electron irradiation and annealing. Strong scattering of phonons by small concentrations of radiation-induced defects is observed. The additive thermal resistivity increases as the 0.58 power of the time integrated flux $\ensuremath{\Phi}$ rather than the first power observed for GaAs. Irradiation to 3.4\ifmmode\times\else\texttimes\fi{}${10}^{18}$ 2-MeV $\frac{e}{{\mathrm{cm}}^{2}}$ below 50\ifmmode^\circ\else\textdegree\fi{}K gave $\frac{1}{K}\ensuremath{-}\frac{1}{{K}_{0}}=1.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}{\ensuremath{\Phi}}^{0.58}$ cm-deg/W at 20\ifmmode^\circ\else\textdegree\fi{}K. For $\ensuremath{\Phi}$ between ${10}^{16}$ and ${10}^{19}$ 2-MeV $\frac{e}{{\mathrm{cm}}^{2}}$, the magnitude of the increase in thermal resistivity of Ge is comparable to that observed for GaAs even though the lattice strain is much smaller. Strain and mass-difference scattering theories cannot explain the Ge data as they can the GaAs data. The Keyes or Pyle phonon-electron scattering theories, however, can explain the Ge results. A small amount of annealing of the additive thermal resistivity was observed to begin at 35\ifmmode^\circ\else\textdegree\fi{}K in the high-purity Ge studied here. This is in agreement with the first annealing stage seen by electrical measurements in degenerate $n$-type Ge by MacKay and Klontz and in degenerate $p$-type Ge by Gobeli. Large recovery states are seen at 125 and 200\ifmmode^\circ\else\textdegree\fi{}K. In the annealing-temperature interval between 140 and 200\ifmmode^\circ\else\textdegree\fi{}K, the thermal conductivity is strongly dependent on electron trapping and can be significantly decreased by a short illumination which changes the charge states of the defects. This demonstrates the phonon-electron scattering nature of the thermal resistivity. Measurements of the temperature dependence of the thermal conductivity indicate that the defects anneal as point defects. The large precipitation of point defects seen in GaAs is not seen in Ge, and almost complete recovery of the radiation-induced defects occurs by 405\ifmmode^\circ\else\textdegree\fi{}K. Minima are observed in the temperature dependence of the thermal conductivity, suggesting localized mode scattering.
The Process of ‘Taking-into-Account’ in Visual Perception:

In order to secure useful information the perceptual system must combine information present in the retinal counterpart of the to-be-discriminated distal variable with information about other varia...
Effective lifetimes in high quality silicon devices

Abstract A correct interpretation of pn junction current-voltage and pulsed MOS capacitance-time data allows space-charge region width dependent generation parameters to be separated from bulk controlled recombination parameters. This is very important for the correct extraction of generation lifetime and minority carrier diffusion length, especially for intrinsically gettered devices where the recombination center density varies through the device. Methods to do this are discussed in this paper.
The development of perceived structure and attention: Evidence from divided and selective attention tasks

Abstract Three experiments provide converging evidence for the view that both perceived structure and attention change during the elementary school years. Kindergarteners, second graders, and adults performed three speeded tasks: divided attention to conjunctions of features, selective attention to orthogonal dimensions, and selective attention to correlated dimensions. The tasks were performed with sizes and shapes that were either spatially integrated or spatially separated. In the divided attention task, conjunctions were identified as quickly as single features with integrated stimuli at all ages, but conjunctions were identified more slowly than single features with separated stimuli by all age groups. In the orthogonal dimensions task, interference was observed with integrated stimuli across ages, but the interference in adult performance was asymmetric. With separated stimuli, interference was gradually eliminated with increasing age. In correlated dimensions tasks, younger children showed a redundancy gain with integrated stimuli, but no gain was observed in the performances of the older subjects. With separated stimuli, there was no redundancy gain at any age. These results were interpreted to mean that integrated stimuli are initially perceived as wholes by all subjects, but that features become more accessible with increasing age. Even so, attention remains constrained by stimulus structure. In contrast, separated stimuli are initially perceived as features at all ages, and the improvement in performance with increasing age is attributable to the increasing command of attentional resources that accompanies development. Our discussion of these findings focuses on three issues: multiple trends in perceptual development, the characteristics of an adequate theory of perceptual representation and processing, and a comparison of the separability hypothesis and other developmental accounts of perceptual development.
Medium-resolution studies of extreme-ultraviolet emission from CO by electron impact.

We report medium-resolution (0.025 nm full width at half maximum (FWHM)) electron impact-induced emission spectra of CO for 20, 100, and 200 eV impact energies. The emission spectra correspond to the extreme ultraviolet transitions from the B (sup 1)Sigma(sup +)(0), and E (sup 1)Pi(0) vibronic states to the X (sup 1)Sigma(sup +)(0) ground state. The present measurements are carried out at 20 times higher spectral resolution (to separate the many blended components) compared to our previous measurements, which were at a spectral resolution of 0.5 nm FWHM. The emission cross sections corresponding to the B (sup 1)Sigma(sup +)(0) yields X (sup 1)Sigma(sup +)(0), C (sup 1)Sigma(sup +)(0) yields X (sup 1)Sigma(sup +)(0), and E (sup 1)Pi(0) yields X (sup 1)Sigma(sup +)(0) resonance transitions were measured. In addition, excitation functions (0-1 keV) extending well into the Born region have been measured for the strong transitions (B (sup 1)Sigma(sup +)(0) yields X (sup 1)Sigma(sup +)(0) and C (sup 1)Sigma(sup +)(0)) and oscillator strengths have been determined, using a modified Born approximation analytic fit to the measured excitation function.
Independence Results about Context-Free Languages and Lower Bounds

Abstract We show that for any axiomatizable, sound formal system F there exist instances of natural problems about context-free languages, lower bounds of computations and P versus NP that are not provable in F for any recursive representation of these problems . Most previous independence results in computer science have been proven for specific representations of the problems, by exploiting the ‘opaqueness’ of Turing machine names. Our results rely on the complexity of the logical structure of the problem and yield independence results which do not depend on the representations of problems. We show, for example, that there exists a nonregular context-free language L 0 such that for no cf-grammar G, L(G) = L 0 , it is provable in F that “L(G) is not regular”. We also show, among other results about P and NP, that there exists a recursive oracle A such that NP A ≠ P A , and that this fact is not provable in F for any recursive representation of A. The difference of what is and is not provable in F is well illustrated by questions about polynomial time isomorphisms (p-isomorphisms) of NP-complete sets. We show that for every NP-complete set, L, there is a representation of L by a nondeterministic polynomial time machine for which we can prove that L is NP-complete. Furthermore, if L is p-isomorphic to SAT, then this is also provable in F for some representation of L. On the other hand, if there exist NP-complete sets not p-isomorphic to SAT, then there exists an NP-complete set L for which, independent of its representation, there is no proof in F that L is or is not p-isomorphic to SAT.
Do Subtle Cues About Belongingness Constrain Women's Career Choices?

Nilanjana Dasgupta's (this issue) stereotype inoculation model (SIM) helps explain why what feels like a free choice to pursue one life path over another “is often constrained by subtle cues in ach...
Rates of exchange of isotopic hydrogen between reduced substrates of coupled NAD-dependant dehydrogenases.

Abstract The exchange of isotopic hydrogen between reduced substrates of coupled NAD-dependant dehydrogenases possessing the same and opposite steric specifities of NADH is considered. Kinetic analysis of the equilibrium state of the interacting systems shows that when dehydrogenases of unlike stereospecificity are paired, two exchanges between labeled NAD and NADH are required before the isotope can be transferred from one substrate to the other whereas no exchanges of this kind are required when dehydrogenases of like stereospecificity for NADH interact. The obligatory exchanges between NAD and NADH reduce the equilibrium velocity of isotope transfer between the substrates. Accordingly the exchanges of hydrogen isotopes between reduced substrates of coupled dehydrogenases possessing opposite stereospecificity for NADH will, in general, be found to be slower than between systems of the same stereospecificity.
75-year-old man with abdominal pain and weight loss.

© 2008 Mayo Foundation for Medical Education and Research A 75-year-old man presented to the outpatient clinic with a 9-kg weight loss during the preceding several months and mild midepigastric pain radiating to the back. His medical history was unremarkable. He was a former smoker and lifelong nondrinker. Review of systems was notable only for a slightly decreased appetite, but no nausea, vomiting, or diarrhea was reported. On physical examination, the patient was afebrile and had normal vital signs. However, cachexia and jaundice with scleral icterus were evident. Abdominal examination revealed mild midepigastric tenderness without rebound, guarding, or hepatosplenomegaly and a negative Murphy sign. Findings on the rest of the physical examination were unremarkable. Results of a complete blood cell count and electrolyte studies were within normal limits. Additional test results included the following (reference ranges provided parenthetically): alanine aminotransferase, 425 U/L (7-55 U/L); aspartate aminotransferase, 127 U/L (8-48 U/L); alkaline phosphatase, 582 U/L (45-115 U/L); total bilirubin, 8.9 mg/dL (0.1-1.10 mg/dL); direct bilirubin, 7.1 mg/dL (0.00.3 mg/dL); and lipase, less than 10 U/L (10-73 U/L). The erythrocyte sedimentation rate was elevated at 71 mm/1 h (0-22 mm/1 h). Hepatitis testing that included hepatitis B surface antigen, IgM antibodies to hepatitis B core antigen, and hepatitis C virus (enzyme immunoassay) yielded normal results.