cssi/SciSciGPT-SciSciNet huggingface dataset:
AC Ring Distribution: Architecture for Subsea Power Distribution

Subsea power transmission and distribution is an emerging technology that may enable the oil and gas industry to produce hydrocarbon reserves in deeper and more remote offshore waters. The longer tieback subsea operations will likely require pumps and compressors driven by electric motors to be located on the sea floor to pressure boost the oil and gas to surface and/or onshore platforms. Existing HVAC and HVDC technologies are efficient means for subsea power transmission and distribution. However, they are subject to a variety of limitations, for instance, the single-point failures that would impact production uptime. Furthermore, it is challenging to implement subsea bulk power transmission and distribution by using existing architectures due to the footprint, weight and electrical insulation requirements. This paper describes a subsea power distribution architecture — AC ring. It can be used to interface a high-voltage bulk power transmission network, either AC or DC, to a subsea multi-load AC system. The new topology uses series-connected, by-passable, open-winding transformers to provide better modular design flexibility. The system is expected to be more reliable than conventional “hub and spoke” architectures and more technically feasible regarding practical subsea equipment designs.Copyright © 2010 by ASME
Effects of Molecular Memory and Bursting on Fluctuations in Gene Expression

Many cellular components are present in such low numbers per cell that random births and deaths of individual molecules can cause substantial "noise" in concentrations. But biochemical events do not necessarily occur in single steps of individual molecules. Some processes are greatly randomized when synthesis or degradation occurs in large bursts of many molecules during a short time interval. Conversely, each birth or death of a macromolecule could involve several small steps, creating a memory between individual events. We present a generalized theory for stochastic gene expression, formulating the variance in protein abundance in terms of the randomness of the individual gene expression events. We show that common types of molecular mechanisms can produce gestation and senescence periods that reduce noise without requiring higher abundances, shorter lifetimes, or any concentration-dependent control loops. We also show that most single-cell experimental methods cannot distinguish between qualitatively different stochastic principles, although this in turn makes such methods better suited for identifying which components introduce fluctuations. Characterizing the random events that give rise to noise in concentrations instead requires dynamic measurements with single-molecule resolution.
A fluorescence technique to distinguish attached from ingested erythrocytes and zymosan particles in phagocytosing macrophages.

While investigating the role of [Ca2+]i in Fc receptor-mediated phagocytosis, we found that clamping the [Ca2+]i to low levels by a variety of methods often led to increased plasma membrane permeability, rendering the hypotonic lysis method for calculating the phagocytosis index unreliable. To overcome this difficulty we developed a method for calculating the phagocytosis index of IgG-coated RBC that does not depend on hypotonic lysis. It depends on the ability of ingested RBC to create dark-appearing phagocytic vacuoles when the cytoplasm of murine macrophages is stained with acridine orange. Uningested or partially ingested RBC do not change the appearance of the otherwise uniformly stained cytoplasm of the macrophages. Since this method does not rely on hypotonic lysis to distinguish attached from ingested RBC, it can be used in situations when macrophages are unusually sensitive to hypotonic treatment (e.g. after clamping the macrophage [Ca2+]i to low levels). It can also be applied to the study of phagocytosis of particles that are not susceptible to hypotonic lysis (e.g., zymosan).
“A Storm in a Tea-Cup”: The Iraq-Kuwait Crisis of 1961 from Gulf Crisis to Inter-Arab Dispute

“A Storm in a Tea-Cup” offers the most detailed survey yet of the international crisis precipitated by Iraq's June 1961 threat to seize control of Kuwait. On the basis of an extensive reading of do...
Cooperative membrane insertion of magainin correlated with its cytolytic activity

Abstract Using oriented circular dichroism, we have found that magainin adopts an α-helical conformation with two distinct orientations when interacting with a lipid bilayer. At low concentrations, magainin is adsorbed parallel to the membrane surface. However, at high concentrations, magainin is inserted into the membrane. This transition occurs at roughly the same critical concentration required for cytolytic activity, implying that the membrane insertion is responsible for magainin's cell-lysing activity.
Bispectral analysis of nonlinear compressional waves in a two-dimensional dusty plasma crystal.

Bispectral analysis was used to study the nonlinear interaction of compressional waves in a two-dimensional strongly coupled dusty plasma. A monolayer of highly charged polymer microspheres was suspended in a plasma sheath. The microspheres interacted with a Yukawa potential and formed a triangular lattice. Two sinusoidal pump waves with different frequencies were excited in the lattice by pushing the particles with modulated Ar{sup +} laser beams. Coherent nonlinear interaction of the pump waves was shown to be the mechanism of generating waves at the sum, difference, and other combination frequencies. However, coherent nonlinear interaction was ruled out for certain combination frequencies, in particular, for the difference frequency below an excitation-power threshold, as predicted by theory.
Multi-pinhole collimator design for small-object imaging with SiliSPECT: a high-resolution SPECT

We have designed a multi-pinhole collimator for a dual-headed, stationary SPECT system that incorporates high-resolution silicon double-sided strip detectors. The compact camera design of our system enables imaging at source–collimator distances between 20 and 30 mm. Our analytical calculations show that using knife-edge pinholes with small-opening angles or cylindrically shaped pinholes in a focused, multi-pinhole configuration in combination with this camera geometry can generate narrow sensitivity profiles across the field of view that can be useful for imaging small objects at high sensitivity and resolution. The current prototype system uses two collimators each containing 127 cylindrically shaped pinholes that are focused toward a target volume. Our goal is imaging objects such as a mouse brain, which could find potential applications in molecular imaging.
Estimating the junction temperature of AC LEDs

Light-emitting diodes operating on alternating current are gaining popularity in the LED industry, especially for lighting applications. Because junction temperature is a good predictor of LED performance, the availability of a method to accurately estimate the junction temperature of AC LEDs would be very useful. This study investigated a method in which a low reference current having a pulse width of less than several milliseconds was applied and the corresponding voltage across the device was measured and correlated to the junction temperature. Laboratory experiment data showed that the proposed method is a promising candidate for estimating AC LED junction temperature.
Voltage-tunable volume transitions in nanoscale films of poly(hydroxyethyl methacrylate) surfaces grafted onto gold.

Surface grafting of a polymerizable monomer onto Au was used to produce nanometer-scale planar hydrogel films with controllable volume. A self-assembled monolayer of 11-mercaptoundecanoic acid on a planar Au surface was activated through water-soluble carbodiimide and N-hyroxysuccinimide followed by reaction with 2-aminomethacrylate to produce a methacrylate-terminated surface layer, which readily polymerized under UV radiation in the presence of hydroxyethyl methacrylate monomer, ethylene glycol dimethacrylate cross-linker, and a photoinitiator. The reaction steps were characterized by external reflection mode Fourier transform IR spectroscopy. Under controlled UV exposure, thin (3 nm < d < 10 nm) hydrogel films were obtained from 1:1 ethanol/H2O. Surface plasmon resonance measurements were used to characterize both the synthesis of the hydrogel and the potential-induced volume changes. The nanometer-scale hydrogels thus produced undergo reproducible changes in thickness, when a potential is applied acro...
Lidocaine-induced heart block in patients with bundle branch block.

Abstract His bundle electrography and atrial pacing were used to evaluate the effect on cardiac conduction of an intravenous bolus injection (50 to 100 mg) of lidocaine in 21 patients with various intraventricular conduction abnormalities and ventricular premature beats. Sixteen patients (76 percent) had prolonged His-Purkinje conduction time (H-V interval greater than 55 msec). Six patients (all with a prolonged H-V interval) had earlier shown transient second degree or complete heart block. Administration of lidocaine produced complete heart block distal to the His bundle potential in two patients. Both patients had a prolonged H-V interval (100 and 140 msec, respectively) and had shown 2:1 A-V block distal to the H deflection on atrial pacing before the injection. A third patient, with an H-V interval of 70 msec, showed second degree block distal to the H deflection during atrial pacing after administration of lidocaine but not before. An additional patient, observed clinically to have alternating right and left bundle branch block, experienced cardiac standstill after the injection. Lidocaine should be used cautiously in patients with incomplete bilateral bundle branch block, and a temporary pacemaker should be considered in patients with a prolonged H-V interval or known trifascicular disease.
Writers and critics: Two types of vocational consciousness in the art system

Abstract Vocational interests, personality, work environment, and background of authors and critics, male and female, in children's literature are examined in terms of Holland's theory of vocational types, supplemented with concepts of an art system and styles of consciousness. On SVIB indicator scales, both authors and critics score as artistic types with “consistent” profiles, but authors are more “differentiated.” Critics have stronger social interests and less aversion to conventional activities, appropriate to their position as gate-keepers in the art system. In work style there are again common features, but authors describe themselves as having “alternative” states of consciousness, where critics emphasize their social roles and rationality. Both groups have peaks on Achievement via Independence (CPI), but the critics are more socially ascendant, efficient, and conventional. Most critics have full-time employment under institutional auspices; most writers do not. Difference in occupations of fathers of authors and critics are consistent with interest patterns of the subjects. Several personality and background findings, including interactions between sex and field, are interpreted as supporting the usefulness of supplementing Holland's theory.
Fast, blind, and joint maximum likelihood estimation of MPSK signal parameters

We present a fast algorithm for the joint maximum likelihood (JML) estimate of information-symbols, phase, amplitude, and noise-variance, given baud-sampled M-ary phase shift keyed signals (MPSK) observed in complex additive white Gaussian noise. The algorithm is fast in that it has a complexity that grows as O(N log 2 N), where N is the number of observed symbols. Further, the algorithm only requires one optional division and one square root, and no other transcendental functions. Finally, the algorithm is parallelizable with N processors in O(log 2 N) time using standard parallelizable processing primitives. The performances for phase, amplitude, and SNR estimation are compared to the Cramer Rao Lower Bound (CRLB) for a data-aided estimator.
Slo3 K+ channels: voltage and pH dependence of macroscopic currents.

The mouse Slo3 gene (KCNMA3) encodes a K+ channel that is regulated by changes in cytosolic pH. Like Slo1 subunits responsible for the Ca2+ and voltage-activated BK-type channel, the Slo3 α subunit contains a pore module with homology to voltage-gated K+ channels and also an extensive cytosolic C terminus thought to be responsible for ligand dependence. For the Slo3 K+ channel, increases in cytosolic pH promote channel activation, but very little is known about many fundamental properties of Slo3 currents. Here we define the dependence of macroscopic conductance on voltage and pH and, in particular, examine Slo3 conductance activated at negative potentials. Using this information, the ability of a Horrigan-Aldrich–type of general allosteric model to account for Slo3 gating is examined. Finally, the pH and voltage dependence of Slo3 activation and deactivation kinetics is reported. The results indicate that Slo3 differs from Slo1 in several important ways. The limiting conductance activated at the most positive potentials exhibits a pH-dependent maximum, suggesting differences in the limiting open probability at different pH. Furthermore, over a 600 mV range of voltages (−300 to +300 mV), Slo3 conductance shifts only about two to three orders of magnitude, and the limiting conductance at negative potentials is relatively voltage independent compared to Slo1. Within the context of the Horrigan-Aldrich model, these results indicate that the intrinsic voltage dependence (zL) of the Slo3 closed–open equilibrium and the coupling (D) between voltage sensor movement are less than in Slo1. The kinetic behavior of Slo3 currents also differs markedly from Slo1. Both activation and deactivation are best described by two exponential components, both of which are only weakly voltage dependent. Qualitatively, the properties of the two kinetic components in the activation time course suggest that increases in pH increase the fraction of more rapidly opening channels.
Device Requirements For Spread-Spectrum Communication

AbstractSpread -sprectrum techniques are widely used in state -of- the -art communication systems for suppression of interference. In this paper we will establish the characteristics required for signal -processing devices usedin such systems. Typical spread- spectrum waveforms will be described to emphasize those characteristicswhich lead to good system performance. The synchronization problem will be reviewed to show that this isoften the most difficult aspect of a communication system design and strongly influences the choice of devices.The performance of any device in a system will reflect some features of the device which are undesirable.Spurious responses can cause errors in detection or demodulation circuitry. A limited dynamic range for asignal -processing device might have the effect of lowering the apparent interference rejection of the system.IntroductionMilitary communication systems have long used spread- spectrum techniques for suppression of interference and jamming. Other advantages are the ability to incorporate privacy and authentication measures directlyinto the modulation waveforms, reduced vulnerability to interception or direction finding, multiplex andmultiple access alternatives, and improved multipath- fading performance. In this paper we will review theantijam capabilities of spread- spectrum communication in order to establish desirable properties of devicesto be used for signal processing in such systems.We shall find that devices which process large time -bandwidth -product waveforms are required, and thatthese devices must be programmable in order to allow frequent waveform changes. Consideration of the synchro-nization problem will shown that this is the most critical aspect of systems which handle multiple users andburst traffic, such that long synchronization times are not tolerable. This will demand devices which performas matched filters or multiple parallel correlators. Finally we will consider performance of devices, acritical issue being the effect of dynamic range on processing gain.Spread- spectrum interference rejectionFor binary communication through a channel perturbed by white Gaussian noise,' it is well known thatthe bit -error rate (BER) for a particular modulation technique is a function of Eb /No, the ratio of theenergy in the bit waveform to the noise spectral density. Increasing the signal bandwidth does not improvethe signal -to -noise ratio because the total noise power is proportional to the bandwidth. The situation isquite different when considering interference due to a power -limited jammer. If a noise jammer is forced tospread its available power across a larger bandwidth, its spectral power density must decrease. Thus, the
The role of shear stresses and shear strains in transformation-toughening

Abstract The effect of shear stresses and shear strains on microstructural development in transformation-toughened materials is studied with a procedure that treats the particles as a distribution of small, circular, transforming spots that surround the tip of a semi-infinite stationary crack. Microstructural simulations were conducted by incrementing a set of remote applied stresses consistent with a mode I K-field on a cracked plane containing untransformed spots. When a critical stress criterion was satisfied at a spot centre, that spot underwent a uniform stress-free transformation strain. Microstructures at crack-growth initiation show that the action of shear strains and the influence of shear stresses have an important effect on the size and shape of the region of transformed spots. The presence of shear can produce transformation zone shapes which are radically different from those predicted by the conventional continuum model of a dilatational strain triggered by a critical level of mean stress.
NDE methods for determining the materials properties of silicon carbide plates

Two types of SiC plates, differing in their manufacturing processes, were interrogated using a variety of NDE techniques. The task of evaluating the materials properties of these plates was a challenge due to their non-uniform thickness. Ultrasound was used to estimate the Young's Modulus and calculate the thickness profile and Poisson's Ratio of the plates. The Young's Modulus profile plots were consistent with the thickness profile plots, indicating that the technique was highly influenced by the non-uniform thickness of the plates. The Poisson's Ratio is calculated from the longitudinal and shear wave velocities. Because the thickness is cancelled out, the result is dependent only on the time of flight of the two wave modes, which can be measured accurately. X-Ray was used to determine if any density variations were present in the plates. None were detected suggesting that the varying time of flight of the acoustic wave is attributed only to variations in the elastic constants and thickness profiles of the plates. Eddy Current was used to plot the conductivity profile. Surprisingly, the conductivity profile of one type of plates varied over a wide range rarely seen in other materials. The other type revealed a uniform conductivity profile.
Resting state functional connectivity in addiction: Lessons learned and a road ahead.

Abstract Despite intensive scientific investigation and public health imperatives, drug addiction treatment outcomes have not significantly improved in more than 50 years. Non-invasive brain imaging has, over the past several decades, contributed important new insights into the neuroplastic adaptations that result from chronic drug intake, but additional experimental approaches and neurobiological hypotheses are needed to better capture the totality of the motivational, affective, cognitive, genetic and pharmacological complexities of the disease. Recent advances in assessing network dynamics through resting-state functional connectivity (rsFC) may allow for such systems-level assessments. In this review, we first summarize the nascent addiction-related rsFC literature and suggest that in using this tool, circuit connectivity may inform specific neurobiological substrates underlying psychological dysfunctions associated with reward, affective and cognitive processing often observed in drug addicts. Using nicotine addiction as an exemplar, we subsequently provide a heuristic framework to guide future research by linking recent findings from intrinsic network connectivity studies with those interrogating nicotine's neuropharmacological actions. Emerging evidence supports a critical role for the insula in nicotine addiction. Likewise, the anterior insula, potentially together with the anterior cingulate cortex, appears to pivotally influence the dynamics between large-scale brain networks subserving internal (default-mode network) and external (executive control network) information processing. We suggest that a better understanding of how the insula modulates the interaction between these networks is critical for elucidating both the cognitive impairments often associated with withdrawal and the performance-enhancing effects of nicotine administration. Such an understanding may be usefully applied in the design and development of novel smoking cessation treatments.
A symbolic interactionist model of leisure: Theory and empirical support

Abstract In recent years there has been concern about the need to strengthen the theoretical foundations of leisure research. The premises of symbolic interaction theory may offer a perspective for understanding the theoretical issues of freedom and constraint within leisure. Typical social interaction is characterized by perceived social role constraint, self‐objectification, and inhibited self‐expression; these may be important dimensions that differentiate leisure from non‐leisure contexts. In this study, 18 individuals provided data on 695 real‐life situations in an experience sampling study. Analysis indicated that role constraint and self‐expression explained 43 percent of the variance in leisure. A typology was created by dichotomizing and cross‐classifying role constraint and self‐expression. Quantitative and qualitative analysis of that model suggested that it generated four distinct social contexts: pure leisure, anomic leisure, enjoyable work, and obligatory task. An advantage of this model rel...
On the temperature coefficient of PCO 2 in seawater

The commonly reported temperature coefficient of P. the equilibrium partial pressure of CO2, is (∂P/∂T) A,C ,which is about 15 ppm/°C, or 5% of the atmospheric partial pressure of CO2. This coefficient, however, applies only to deep water, not to surface water which can exchange CO2 with the atmosphere. The coefficient (∂P/∂T) A,C ,, where σ designates constancy of the sum of atmospheric and surface-ocean CO2, is the appropriate value for air-sea exchange. Numerical values are mass-dependent because the depth of the exchanging ocean layer must be specified. For a 100-m surface layer, the value is ca. 1.5 ppm/°C, or 0.5% of ambient CO2.
Functional connectivity with the anterior cingulate is associated with extraversion during the emotional Stroop task

Previous research has investigated the association of personality traits with brain activation in response to emotional stimuli. Our current research efforts are directed at understanding the temporal dynamics of networks of structures associated with particular personality traits, and gain insights into the functional contributions of more narrowly defined trait-facets that comprise these personality traits. To begin this process, we conducted a functional magnetic resonance imaging (fMRI) study using an emotional attention task (emotional Stroop paradigm) and addressed the question whether individual differences in extraversion and its lower-level facets were associated with differences in activation, and in functional connectivity, of the anterior cingulate (AC) cortex. We replicated our earlier finding that extraversion was associated with increased AC activation to positive, relative to neutral, word stimuli, but now show that distinct facets of extraversion can account for this association. When analyzing for functional connectivity, we found that greater extraversion across individuals was associated with greater functional connectivity between the AC and the inferior parietal lobule, and that this association could also be accounted for by distinct facets of extraversion. Our data suggest that extraversion and some of its lower-level facets are associated with individual differences across a network of structures believed to be critical in cognitive and affective processing.
Meningeal cells and glia establish a permissive environment for axon regeneration after spinal cord injury in newts

Background Newts have the remarkable ability to regenerate their spinal cords as adults. Their spinal cords regenerate with the regenerating tail after tail amputation, as well as after a gap-inducing spinal cord injury (SCI), such as a complete transection. While most studies on newt spinal cord regeneration have focused on events occurring after tail amputation, less attention has been given to events occurring after an SCI, a context that is more relevant to human SCI. Our goal was to use modern labeling and imaging techniques to observe axons regenerating across a complete transection injury and determine how cells and the extracellular matrix in the injury site might contribute to the regenerative process.
Prolonged depressive behaviors in a recently blinded deaf mute: A behavioral treatment

Abstract A sequence of programs using positive reinforcement was administered to increase appropriate dressing, watch wearing, and occupational therapy attendance in a recently blinded deaf mute who was depressed and relatively uncommunicative. An irregular sleeping pattern was markedly reduced by restricting daytime sleeping. Other behaviors, not directly manipulated, changed in frequency during hospitalization. The results indicate that behavior modification procedures can be useful in dealing with blind individuals who are not otherwise able to benefit from rehabilitation programs.
Interstitial thermoradiotherapy with ferromagnetic implants for locally advanced and recurrent neoplasms

Abstract Purpose: The University of Arizona, University of California at San Francisco, City of Hope Medical Center, and University of Wisconsin participated in a Phase I/II protocol to assess the heating ability and the toxicity of interstitial thermoradiotherapy using ferromagnetic implantation. Methods and Materials: Forty-four patients with advanced primary or recurrent extra-cranial solid malignancies were enrolled in this study. Fourteen gauge catheters were implanted into tumors and, once in the department of Radiation Oncology, loaded with ferromagnetic seeds to deliver a 60 min hyperthermia treatment. Multi-point thermometry was continuously used throughout the heating sessions for all patients, sampling the periphery as well as the core of the tumor. After 192 Iridium brachytherapy, 18 patients then had an additional treatment. The mean radiation dose while on protocol was 50.0 Gy, with total doses (including prior radiotherapy) ranging from 20.3–151.8 Gy (median = 88.7 Gy). Response and toxicity were assessed by inspection, palpation, and/or radiologic studies. Forty-one patients were evaluable for response, and there were 55 analyzable hyperthermia treatment sessions. Results: The complete response rate was 61% (25/41). The partial response rate was 31.7% and only 7.3% failed to respond. Median duration of local control has not yet been reached. The mean maximum, minimum, and mean time-averaged temperatures for all in-tissue sensors were 43.7°C, and 41.0°C, respectively. Tumor size was the only factor significantly correlated with temperatures or with complete response rate; larger tumors attained higher temperatures but smaller tumors had a higher response probability. Nineteen patients (43%) experienced toxicities, however there was only a 7% (3/44) rate of serious complications (Grade 3 or 4). Prior treatment with hyperthermia was the only factor significantly correlated with serious toxicity. Conclusion: These results, a 93% total response with only 7% serious toxicity, are encouraging especially in the context of the patient population treated. Phase II/III studies involving ferromagnetic implantation are warranted.
Three Cups of Tea: Building Collaborations to Assess Earthquake Hazard in Pakistan: Modern Methods in Seismic Hazard Assessment; Nagarkot, Nepal, 8–12 June 2009

The M7.6 Muzaffarabad, Pakistan, earthquake struck the Pakistani Kashmir on 8 October 2005, claiming more than 80,000 lives. The earthquake underscored two points about earthquake hazard in Pakistan: first, that it is high, and, second, that it is poorly understood. In Karachi, for example, hazard is generally considered to be low, yet this rapidly growing megacity is as close to a major strike-slip fault system as Los Angeles is to the San Andreas fault. The Pakistani engineering community has sought guidance from seismologists on improved characterization of seismic hazard. This requires both improved hazard assessment methodology and improved constraints on the critical inputs to seismic hazard maps, for example, assessment of fault slip rates and geological site characterization. These inputs are currently unavailable. Efforts to map seismicity and attenuation and to estimate fault slip rates have been hampered by political instability. Yet there is no shortage of intellectual energy—Pakistan boasts an eager community of trained earthquake professionals.
Compensators for three-dimensional treatment planning

Presented here is a method of designing compensators for a single beam or one or more pairs of beams, not necessarily parallel opposed. The objective is to produce a flat distribution in a plane that may be perpendicular to the central ray or may be an arbitrarily oriented plane, for example, a plane that bisects the hinge angle between two beams. The method takes into account not only surface irregularities but also tissue inhomogeneities, hinge angles between beams, distance from the source, and even ‘‘horns’’ in the beam. The design process employs convolution of Monte Carlo generated pencil beams with photon fluence distributions, appropriately modified for the presence of beam modifiers (blocks and compensators), to compute dose in a flat homogeneous phantom. Corrections for inhomogeneities and surface curvature are applied by using computerized tomography information to determine the effective path length through tissue. Multiple interations are used to arrive at a compensator that properly incorporates changes in radiation transport, and therefore dose distribution, resulting from the presence of beam‐shaping devices. In each iteration it is assumed that the required reduction in dose at a point can be achieved by reducing the fluence along the ray joining the source to computation point proportionately. The compensator design is represented as a finely spaced matrix of thickness values which is entered into a prorammable milling maching for fabrication. Dose measurements in phantom exposed to 6‐MV x rays with and without compensation are presented.
Videofluoroscopic upper esophageal sphincter function in elderly dysphagic patients

Objectives/Hypothesis The intent of the study was to identify and characterize abnormalities of the timing and extent of upper esophageal sphincter (UES) opening in an elderly population complaining of dysphagia. Study Design A retrospective review of dynamic swallow studies performed on patients greater than 65 years of age without an obvious medical or surgical cause for their dysphagia. Methods Measures of UES opening timing and extent in the patient population were compared with those from 60 young, normal control subjects and 23 elderly control subjects. The relationship of UES function and other swallowing abnormalities was also evaluated. Results No decrease in the size of UES opening was identified in the patient population. The coordination of UES opening relative to the position of the bolus in the pharynx was normal. UES opening was prolonged and was correlated with poor pharyngeal clearing suggestive of weak pharyngeal constriction. Conclusion No primary abnormality of UES function was identified in this elderly dysphagic patient population.
The Passage of Neutrons Through Crystals and Polycrystals

We investigate in this paper phenomena, occurring in the passage of neutrons through matter, which originate from the crystalline or polycrystalline constitution. While the procedure is in many respects closely similar to that followed in the theory of x-rays, important and quantitatively decisive differences arise from the complicated coherence properties of the atomic scattering. The theoretical formulae developed in the first two paragraphs permit us to interpret in a quantitative manner a series of experiments which show deviations from the so far almost always assumed additivity of nuclear cross sections. We also obtain information concerning the relative phases of the scattering amplitudes of nuclear isotopes. We next show for illustrative purposes how the Larmor precession of the spin of the neutron passing through the magnetized medium, and the well-known differentiation between the action of the vectors "$B$" and "$H$" can be explained as a simple dispersion phenomenon. The preceding formulae permit us to determine quantitatively the transmission and polarization of neutron beams passing through ferromagnetic bodies. The main uncertainties which enter into attempts to evaluate experiments, arise from our incomplete knowledge of the velocity distribution of the incident beam and of the form factor which enters into the formulae for magnetic scattering. We present a detailed discussion of these uncertainties. Even neglecting depolarization effects which are due to incomplete saturation and which would still further diminish the theoretical value for transmission effects, we find that the observed values are considerably higher than those theoretically predicted and are not in good agreement with each other.
Variation in Drosophila melanogaster central metabolic genes appears driven by natural selection both within and between populations

In this report, we examine the hypothesis that the drivers of latitudinal selection observed in the eastern US Drosophila melanogaster populations are reiterated within seasons in a temperate orchard population in Pennsylvania, USA. Specifically, we ask whether alleles that are apparently favoured in northern populations are also favoured early in the spring, and decrease in frequency from the spring to autumn with the population expansion. We use SNP data collected for 46 metabolic genes and 128 SNPs representing the central metabolic pathway and examine for the aggregate SNP allele frequencies whether the association of allele change with latitude and that with increasing days of spring–autumn season are reversed. Testing by random permutation, we observe a highly significant negative correlation between these associations that is consistent with this expectation. This correlation is stronger when we confine our analysis to only those alleles that show significant latitudinal changes. This pattern is not caused by association with chromosomal inversions. When data are resampled using SNPs for amino acid change the relationship is not significant but is supported when SNPs associated with cis-expression are only considered. Our results suggest that climate factors driving latitudinal molecular variation in a metabolic pathway are related to those operating on a seasonal level within populations.
In vivo detection of an 125I seed located in the intracardiac region after prostate permanent brachytherapy.

Abstract Purpose The purpose of this investigation is to determine the mechanism of seed migration after prostate implant and to develop procedures to minimize the risk of seed migration. Methods and materials Radioactivity survey of prostate cancer patients after permanent brachytherapy with 125 I to detect pulmonary seed embolization is routinely performed using a seed migration detector. The seed migration detector is made from a low-energy, high-sensitivity scintillation survey meter by adding a single-hole collimation cap to the scintillation probe. If a seed migration is suspected, a pair of chest radiographs is ordered to document the location of the migrated seed. A comprehensive investigation is elicited if there are discrepancies between the seed migration detector survey and the radiographic examination. Results One hundred five patients have been surveyed, and 20 patients have demonstrated pulmonary seed embolization. In 1 patient, the seed migration detector sensed radioactivity in the thorax, but repeat chest radiographic examinations failed to show a radiopaque foreign body in the chest cavity. Owing to the signal variation mimicking heart rate, an 125 I seed located in the intracardiac region was suspected. This suspicion was confirmed in a high-quality fluoroscopy examination. Conclusions Seed embolization to the intracardiac region is rarely reported. The true rate may be higher, but has not been adequately documented owing to the limitation of diagnostic quality of chest radiographs to detect seed migration to the intracardiac region. The seed migration detector, on the other hand, demonstrated its efficacy in the detection of seed migration, particularly in the detection of a seed located in the intracardiac region.
On the physical layer security of backscatter RFID systems

Securing radio frequency identification (RFID) systems against malicious attacks such as eavesdropping is a highly challenging task due to the resource constrained nature of such systems. In fact, the modest computational and storage capabilities of RFID tags makes it impossible to adopt classical cryptographic techniques. While existing work has mostly focused on lightweight cryptographic techniques, in this paper, the first analysis on the adoption of physical layer security techniques in an RFID system is presented. First, the secrecy rate of ultra high frequency (UHF) RFID backscatter systems is characterized. Then, a novel approach is proposed for maximizing this secrecy rate by exploiting the nature and features of the RFID backscatter channel. To explore these features, the proposed approach allows the RFID readers to append artificial noise signals to their continuous wave (CW) signals which then propagate via the backscatter channel hence inducing interference at the eavesdroppers. For enabling the readers to optimally allocate power between their CW signals and artificial noise, a noncooperative game is formulated using which the readers can decide on their optimal power allocations so as to maximize their overall secrecy rates, given the ensuing inter-reader interference. For solving this game, a best response algorithm is proposed using which the readers can reach a Nash equilibrium. Simulation results show that the proposed approach yields significant performance gains, in terms of the average secrecy rate per RFID reader, of at least 17% relative to the classical RFID operation.
Changes in adsorbed fibrinogen upon conversion to fibrin.

The conversion of adsorbed fibrinogen to fibrin in the presence of the enzyme thrombin was studied using surface plasmon resonance (SPR), a quartz crystal microbalance (QCM), sum frequency generation (SFG), atomic force microscopy (AFM), and an elutability assay. Exposure of adsorbed fibrinogen to thrombin resulted in a mass loss at the surface consistent with fibrinopeptide release and conversion to fibrin. Changes in hydration upon conversion of adsorbed fibrinogen to fibrin were determined from comparisons of acoustic (QCM) and optical (SPR) mass adsorption data. Conversion to fibrin also resulted in the adsorbed layer becoming more strongly bound to the surface and more compact. The elutability of adsorbed fibrinogen by Triton X-100, studied with SPR, decreased from 90 ± 5 to 6 ± 2% after conversion to fibrin. The height of the adsorbed monolayer, as determined by AFM, decreased from 5.5 ± 2.2 to 1.7 ± 0.8 nm. We conclude that thrombin-catalyzed fibrinopeptide release triggers significant changes in f...
Regional variation of brain gangliosides in feline GM1 gangliosidosis

The morphopathologic abnormalities characterizing the gangliosidoses, e.g., meganeurites and aberrant secondary neurites with associated dendritic spines and synapses, show pronounced regional variation. Because gangliosides are thought to be the causative agents, we undertook to detect possible variation in concentration or composition that would correlate with those morphologic findings. A gradient in total ganglioside and GM1 concentration was found corresponding to cerebral cortex greater than caudate = thalamus greater than cerebellum, similar to the morphologic gradient. In addition, the fatty acid compositions were variable, the proportion of docosanoate (22:0) following the same gradient. The possibility that these variations in ganglioside content and composition might influence the growth of aberrant neurites and related structures is discussed.
IPO underpricing over time: evidence from the UK

The changing nature of initial public offering (IPO) underpricing is examined using a sample of 513 IPOs launched in the UK from 1993 to 2001. It is found that the mean UK underpricing is initially less than that in the USA, reverses itself in the mid-1990s, returns to a lower level during the bubble period, but exceeds US underpricing for the last years of the sample. A growing amount of money left-on-the-table by UK underwriters is also observed. The analysis of IPO characteristics shows the simultaneous presence of changing composition and incentive realignment effects in the UK IPO market. These effects are most evident during the technology/internet equity bubble, which spans the last two subperiods of this study. It is concluded that although the market frenzy of the technology/internet bubble was present in the UK IPO market, its influence appears more limited than that documented for the US.
Multiphoton-vacuum-ultraviolet laser photodissociation of acetylene: Emission from electronically excited fragments

Abstract Acetylene is photolyzed with a high power ArF pulsed excimer laser at 193 nm. Weak CH(A2Δ→X2Π) emission at 431.8 nm is shown to result from two-photon absorption by C2H2, while strong C2(A1Π→1Σg+) Phillips band emission between 690 and 1100 nm likely results from secondary absorption by the C2H fragment. Weak C2(d3Πg→a3Πu) Swan band emission between 440 and 560 nm originates from a three-photon process. In addition, the C2(C1Πg→A1Πu) Deslandres-d'Azambuja system is identified as weak emission bands in the near UV, overlapping an apparent continuum which extends throughout the visible. Radiative lifetimes of 119 ±6 ns and 10.1 ± 1.2 μs are measured for the C2d3Πg(υ′= 0), and A1Πu(υ′ = 4) states, respectively. The present results indicate that it is possible to generate large yields of high energy fragments with pulsed excimer lasers, opening up an energy region which was only previously accessible with far-vacuum-UV photolysis sources. Such fragments can be spectroscopically characterized, or can be used as reactants in kinetic studies.
The Influence of Culture-Specific Background Knowledge and Captions on Second Language Comprehension

The purpose of this study was to examine the effects of caption availability on advanced university-level ESL students' comprehension of contrasting, religion-specific video material. Seventy-nine advanced ESL students participated in the study. Fifty-four of these students reported that they were religion-neutral, having very little or no knowledge of Buddhist or Muslim religious rites. Sixteen students self-reported being practicing Muslims, and nine of the students self-reported being practicing Buddhists. The videotaped episodes consisted of two excerpts from a series of public television broadcasts concerning world religions. The first episode (9 min., 25 sec.) presented information about the Muslim religion and the second episode (10 min., 11 sec.) displayed information about Buddhism. The students were enrolled in six different sections of an intensive English course and participated as intact groups. Each group viewed the Muslim episode once with or without captions, and the Buddhist episode once ...
Focal angiographic abnormalities with subdural empyema

Thirteen patients with subdural empyema underwent arteriography preoperatively and three were restudied postoperatively. Arterial vascular changes were found in nine cases and consisted of localized or diffuse arterial irregularities. In two cases the arterial changes resolved with effective therapy. These arterial changes are similar in appearance and response to therapy to those noted with meningitis; however, in this series they were shown to have occurred in seven cases with subdural empyema but without associated meningitis. Therefore, subdural empyema alone may cause localized or diffuse arterial irregularities.
Alignment and Maintenance Issues for Upstream Cable Plant

As the cable industry activates the return path, many problems have surfaced. To no ones surprise, many papers have been written to address these problems over the last couple of years. This paper will summarize these issues and discuss alignment and measurement approaches in an attempt to solve some of these problems. We have divided the discussion into two sections, initial return path alignment and suggestions for continuing maintenance.
Experience report: Haskell as a reagent: results and observations on the use of Haskell in a python project

In system administration, the languages of choice for solving automation tasks are scripting languages, owing to their flexibility, extensive library support and quick development cycle. Functional programming is more likely to be found in software development teams and the academic world.This separation means that system administrators cannot use the most effective tool for a given problem; in an ideal world, we should be able to mix and match different languages, based on the problem at hand.This experience report details our initial introduction and use of Haskell in a mature, medium size project implemented in Python. We also analyse the interaction between the two languages, and show how Haskell has excelled at solving a particular type of real-world problems
Computerized Adaptive Mastery Tests as Expert Systems

Expert systems can be used to aid decision making. A computerized adaptive test is one kind of expert system, though not commonly recognized as such. A new approach, termed EXSPRT, was devised that...
The role of sexual satisfaction, age, and cardiac risk factors in the reduction of post-MI anxiety.

Background: Anxiety is common after myocardial infarction (MI); however, little is known about the role of sexual satisfaction and return to sexual activity on anxiety post-MI.Aim: To examine the r...
Optimization Problem in Fractional Ownership Operations

[Abstract] The planning phases for the air transportation services generally include fleet assignment, aircraft routing, and crew scheduling. Each phase is widely studied independently in commercial airlines pr actice. In this paper, we present an integrated model to simultaneously solve the three problems for the flexible fractional ownership operations. A mixed -integer programming model is proposed . The model incorporates maintenance events, as well as crew rea ssignment operations. We also investigate the dynamic feature of the transportation mode with real data. Moreover, the model supports to decision making on special strategies.