cssi/SciSciGPT-SciSciNet huggingface dataset:
Space-charge effects in free-electron lasers

Abstract The questions of the importance and proper description of space-charge effects in free-electron lasers are addressed. The collective Raman regime occurs in free-electron lasers when the electron charge density is sufficiently high that the space-charge potential associated with the beam space-charge waves becomes dominant over the ponderomotive potential. The theoretical nonlinear treatment of collective effects in three-dimensions is discussed, and four intense electron beam experiments are analyzed with the objective of determining the importance of Raman effects on the interactions. Three of these experiments used a helical wiggler and an axial guide field, while the fourth used a planar wiggler. For each of these experiments, the usual well-known Raman/Compton criterion predicts that space-charge effects will be important. However, a three-dimensional analysis of these experiments indicates that only two of these experiments were in the Raman regime. Three essential conclusions are drawn. First, the usual Raman/Compton criterion which was derived via an idealized one-dimensional analysis must be used with caution since three-dimensional effects can alter the relative importance of the ponderomotive and space-charge potentials. In addition, 1) the Raman shift in the resonance condition must be greater than the FEL linewidth, and 2) Landau damping of the space-charge waves must be small in order for space-charge effects to be important.
Nonlinear waves in gases

Abstract The method of characteristic perturbation is used to analyze the main features of small amplitude waves generated by a planar piston-like surface in a perfectly conducting gas. The nonlinear effects and the effect of a magnetic field on the wave motion are fully taken into account in the analysis. The trajectory of the wave, the particle path in the physical plane, and the speed of propagation for a weak shock wave are calculated. From the calculation, it is clear that the speed of propagation for a weak shock wave is the average of the characteristic speeds on both its sides. It is also found, in the case of central expansion waves, that the gas velocity is not influenced by the magnetic field, whereas the pressure and the density are lowered in comparison to what they would be in the absence of a magnetic field.
The assassination of Olof Palme: Evidence and ideology

In February 1986, the Swedish premier was assassinated in a crime of political violence that remains unsolved at the time of writing. The present paper examines the various explanations that were proposed for this act, both in Sweden and in other Western countries. It will be shown how these explanations changed as the scope of the investigation grew in complexity and how investigators deviated more and more sharply from the ‘official’ Western view of terrorism. From early suspicion of traditional villains — Middle Eastern separatists or German leftists — attention has focused more recently on very different candidates, in Swedish business and intelligence circles. The aim of the paper is neither to solve the crime nor to produce any new evidence, but to study the changing ideological assumptions of the investigative process, particularly when dealing with sensitive political offenses.
A New Procedure for the Extraction of Unconjugated Steroids from Plasma and Urine

Abstract A procedure is described for the extraction of nanogram quantities of steroids from plasma and urine. The method involves saturation of a diluted plasma or urine sample with ammonium carbonate and extraction with an organic solvent. The application of this method to the analysis of cortisol and unconjugated estriol in plasma and to the analysis of unconjugated steroids in the urine of the newborn infant is described.
Effect of nicotine on the proestrous ovulatory surge of LH in the rat.

Female rats on a lighting schedule with lights on daily from 0500–1900 hr were injected with nicotine tartrate at 1200, 1400, 1600 and 1700 on the afternoon of proestrus. Practically all ovulated that night. However, radioimmunoassay of blood collected by heart puncture from these rats at 1800, 1830 and 1930 revealed low levels of circulating luteinizing hormone (LH). Furthermore, in these animals pentobarbital administered as late as 1800 was effective in blocking ovulation. Insertion of an intra-atrial cannula on the morning of proestrus permitted easy successive sampling of blood throughout the evening of proestrus without anesthesia. Rats injected with nicotine at 1200, 1400 and 1600 showed approximately a two-hr delay in the LH peak, which was also smaller in amplitude than that seen in salineinjected animals. A fourth injection of nicotine at 1700 further reduced and delayed the LH peak an additional 2 hr. Administration of nicotine tartrate (5 mg/kg) every 30 min from 1400–1900 failed to prevent ov...
Effects of temperature and concentration on the energy transfer process between erbium and holmium in yttrium aluminum garnet

Abstract We have studied the energy transfer process between Er 3+ and Ho 3+ in YAG by measuring the spectral distribution and the decay patterns of the infrared fluorescence of three samples: YAG: Er (2%), Ho (0.2%), YAG: Er (50%), Ho (2%) and YAG: Er (50%), Tm (6.7%), Ho (1.7%) in a wide range of temperatures 77–700°K. In the first sample the energy transfer process is found to be more efficient at low temperature as shown by the temperature dependence of the Er and Ho fluorescence intensity, the Ho excitation spectrum and the Er and Ho decay patterns. The decay pattern of Er is purely exponential at all temperatures with a lifetime which goes from 3.6 msec at 130°K to 7.6 msec at 575°K. The decay pattern of the Ho fluorescence shows a rise, followed by an exponential decay. In the two other samples, the energy transfer process is very efficient on account of the high Er concentration, as shown by the disappearance of the Er fluorescence, the great enhancement of the Ho fluorescence and the purely exponential decay of the Ho fluorescence. The efficiency of the energy transfer process is so great at all temperatures as to make any variation of it due to temperature unnoticeable. Correspondingly, the Ho fluorescence intensity has the same temperature dependence as the lifetime. The above results are explained in terms of a cross-relaxation model involving the Er and Ho metastable levels.
Loss of Tumor-Initiating Cell Activity in Cyclophosphamide-Treated Breast Xenografts

Cancer stem cells (CSCs) are a subpopulation of tumor cells with preferential tumor-initiating capacity and have been purported to be resistant to chemotherapy. It has been shown that breast CSC are, on average, enriched in patient tumors after combination neoadjuvant chemotherapy including docetaxel, doxorubicin, and cyclophosphamide (CPA). Here, we investigate the resistance of breast CSC to CPA alone in a xenograft model. CPA treatment led to a 48% reduction in tumor volume during a 2-week period. Cells bearing the CD44+ CD24- phenotype were reduced by 90% (2.5% to 0.24%) in CPA-treated tumors, whereas cells with aldehyde dehydrogenase activity were reduced by 64% (4.7% to 1.7%). A subsequent functional analysis showed that CPA-treated tumors were impaired in their ability to form tumors, indicating loss of functional tumor-initiating activity. These results are consistent with a CSC phenotype that is sensitive to CPA and indicate that some patient CSC may not display the expected resistance to therapy. Deciphering the mechanism for this difference may lead to therapies to counteract resistance.
Bedside catheterization of the left ventricle

Abstract Left ventricular catheterization at the bedside without the aid of fluoroscopy was accomplished successfully in 38 of 46 acutely ill patients with the use of a specially curved polyethylene catheter introduced percutaneously in the femoral artery. The procedure could be accomplished quickly and with no serious complications. This simplified technique may make left ventricular pressure monitoring a practical diagnostic and therapeutic guide in certain patients with shock.
Stacking fault energy determinations in hcp silver-tin alloys☆

Abstract Measurements of the intrinsic stacking fault energy as a function of tin solute concentration are reported throughout the range of the intermediate hexagonal ζ-phase. Four different alloy compositions from 12 to 17 at. % tin were studied. Extended dislocation nodes and dislocation double ribbons were observed and measured. The stacking fault energy values obtained from measurements on these two configurations were in good agreement and indicated that the magnitude of the stacking fault energy increased linearly with solute concentration in the hcp phase. These results are compared with those from cubic α-phase Ag-Sn alloys previously reported. The dislocation configurations in the hexagonal alloys are briefly described.
X-ray photoelectron spectroscopy studies of xanthate adsorption on pyrite mineral surfaces

Abstract XPS spectra have been measured for the surfaces of pyrite before and after treatment with oxygenated and oxygen-free solutions with and without potassium ethyl xanthate. There is general agreement that the active collector formed on pyrite in oxygenated solutions of xanthate is dixanthogen. Therefore this system has been observed in an attempt to characterize surfaced adsorbed dixanthogen by XPS. By contrast, little is known about the active collector formed on pyrite in oxygen-free solutions. Thus, an attempt has been made to use XPS to observe this compound. The “dry” pyrite contains submonolayer amounts of FeS and the intermediate oxidation products hydrated FeOOH, SO 2(ad) , and SO 3(ad) . In addition, hydrocarbons and oxygen-containing carbon species are present as contaminants on the surface. Surfaces treated in oxygen-free solution show a small increase in hydrated FeOOH; in oxygenated solution the mineral surface undergoes extensive oxidation to hydrated FeOOH. Xanthate in either oxygenated or oxygen-free solutions inhibits the oxidation of the mineral surface. In addition, surface hydrocarbon is greatly reduced. Thus, auxiliary functions of xanthate may be explored by XPS. Likewise, adsorbed xanthate and Fe(III)-xanthate complexes are demonstrated to be at most minor forms of xanthate on the surface.
Plasma free fatty acid response to the administration of chorionic "growth hormone-prolactin".

In 4 children with documented hypopituitary dwarfism human chorionic “growth hormone-prolactin” (CGP) elicited a sharp, reproducible rise in the concentration of plasma free fatty acids within 4 hr when 100–400 mg was administered intramuscularly. The pattern of response simulated that of human growth hormone (HGH). The blood glucose concentration did not vary significantly from control studies. The apparent lipolytic effect of CGP in the absence of HGH provides supportive evidence of a growth hormone-like action for the placental hormone and of its important metabolic function during pregnancy.
Two new species of Besleria (Gesneriaceae) from Panama

Besleria formicaria andB. subulata, both with ants inhabiting the midrib region, are described as new and illustrated.
Time-resolved spectroscopy of multiexcitonic decay in an InAs quantum dot

The multiexcitonic decay process in a single InAs quantum dot is studied through high-resolution time-resolved spectroscopy. A cascaded emission sequence involving three spectral lines is seen that is described well over a wide range of pump powers by a simple model. The measured biexcitonic decay rate is about 1.5 times the single-exciton decay rate. This ratio suggests the presence of selection rules, as well as a significant effect of the Coulomb interaction on the biexcitonic wave function.
Can the Bogoliubov-de Gennes equation be interpreted as a `one-particle' wave equation?

Abstract The solutions of the Bogoliubov–de Gennes (BdG) equation are usually interpreted as the excitations from the superconducting ground state. This viewpoint is not easily applied to a strongly coupled heterojunction since the ground state changes across the interface and it is not clear how the ground state should be connected across the heterointerface. In this paper, we present a different viewpoint that does not suffer from this conceptual drawback. We show that the BdG equation can be viewed as a ‘one-particle’ wave equation whose eigenstates (including the negative energy states) can be filled up systematically to describe the superconducting state, in much the same way that we fill the eigenstates of the Schrodinger equation to describe normal conductors. The only difference is that we need to start from a special vacuum | V〉, consisting of a full band of down-spin electrons, instead of the usual vacuum devoid of all particles. Any quantity of interest, A (such as the charge density or the current density), can be interpreted as the sum of a ‘vacuum contribution’AV ACdue to the vacuum | V〉 and a one-particle contribution ABdGdue to the filled eigenstates of the BdG equation. This picture is easily applied even to strongly coupled heterojunctions since the vacuum | V〉 is the same on both sides of a heterointerface. As such, we believe it puts the scattering theory of transport for superconductors on a firmer conceptual basis.
The biological response to the 1977 regime shift in the California Current

Among the least understood interactions between physics and biology in the oceans are those that take place on the decadal scale. But this temporal scale is important because some of the greatest ecological events take place on this time scale. More than 50 years of measurement in the California Current System have revealed significant ecosystem changes, including a large, decadal decline in zooplankton biomass, along with a rise in upper-ocean temperature. The temperature change was a relatively abrupt shift around 1976–77, concurrent with other basin-wide changes associated with an intensification of the Aleutian Low-pressure system. This intensification generates temperature anomalies in the ocean by altering the patterns of net surface-heat fluxes, turbulent mixing, and horizontal transport. Changes in the mean abundance of zooplankton in the southern California Current have been attributed to variations in the strength of coastal upwelling, variations in the horizontal transport of nutrient-rich water from the north, or increased stratification due to warming, all of which could be affected by fluctuations in the Aleutian Low. Here we show that a deepening of the thermocline accompanied the warming and increased the stratification of the water column, leading to a decrease in the supply of plant nutrients to the upper layers. This is the most likely mechanism for the observed plankton decline, and subsequent ecosystem changes. A global change in upper-ocean heat content, accompanied by an increase in stratification and mixed-layer deepening relative to the critical depth for net production, could lead to a widespread decline in plankton abundance.
Energy management of embedded wireless systems through voltage and modulation scaling under probabilistic workloads

Many wireless embedded systems must deal with increasingly complex and time-varying workloads. Moreover, real-time constraints must be satisfied. Most of the existing energy management studies for such systems have focused on relatively simple models that assume deterministic workloads and consider a limited range of energy management techniques, including Dynamic Voltage Scaling (DVS). Our paper addresses these deficiencies by proposing a general purpose probabilistic workload model for computation and communication. To account for the importance of radio energy consumption, we also analyse Dynamic Modulation Scaling (DMS), an often overlooked method for energy management. We define several energy control algorithms, including an optimal combined DVS-DMS approach, and evaluate these algorithms under a wide range of workload values and hardware settings. Our results illustrate the benefits of various power control algorithms.
Training image classifiers with similarity metrics, linear programming, and minimal supervision

Image classification is a classical computer vision problem with applications to semantic image annotation, querying, and indexing. Recent and effective generative techniques assume Gaussianity, rely on distance metrics, and estimate distributions, but are unfortunately not convex nor keep computational architecture in mind. We propose image content classification through convex linear programming using similarity metrics rather than commonly-used Mahalanobis distances. The algorithm is solved through a hybrid iterative method that takes advantage of optimization space properties. Our optimization problem uses dot products in the feature space exclusively, and therefore can be extended to non-linear kernel functions in the transductive setting.
The Role of Endothelium and Nitric Oxide in Rat Pial Arteriolar Dilatory Responses to CO2 In Vivo

Using a closed cranial window system and intravital microscopy/videometry, we studied the rat pial arteriolar (30–60 μm) responses to CO2 before and following a light/dye (L/D) endothelial injury or topical application of the nitric oxide synthase (NOS) inhibitor, nitro-l-arginine (L-NA) or its inactive form, D-NA. L/D treatment consisted of intravenous injection of sodium fluorescein and the illumination (for 90 s) of arteriolar discrete segments on the cortical surface with light from a mercury lamp. Functional changes in pial arteriolar endothelium were characterized by evaluating responses to topical application of acetylcholine (Ach, 5 × 10−4M) and to intravenous (i.v.) oxotremorine (OXO, a stable blood–brain barrier permeant muscarinic agonist, 1 μg kg−1 min−1). After the L/D injury, dilation to Ach was absent whereas dilations to the NO donor, S-nitrosoacetyl-penicillamine (SNAP, 10−5M) and to CO2 (5%) were unchanged (Paco2 = 70 mm Hg). Loss of Ach response but intact SNAP response confirmed functi...
On “Entropy consumption in primary photosynthesis” by Jennings et al.

The preceding paper [R.C. Jennings, E. Belgio, A.P. Casazza, F.M. Garlaschi, G. Zucchelli, Entropy consumption in primary photosynthesis, Biochim. Biophys. Acta (in press)] is criticized on several grounds.
Volcanism and massive sulfide formation at a sedimented spreading center, Escanaba Trough, Gorda Ridge, northeast Pacific Ocean

Seismic-reflection profiles over the sediment-filled Escanaba Trough at the southern Gorda Ridge reveal a series of volcanic centers that pierce the sediment. The volcanic edifices are 3 to 6 km in diameter and are spaced at 15 to 20 km intervals along the axis of the trough. The volcanic intrusions have uplifted the sediment as much as 100 m, and in places fresh basaltic flows are exposed at the sea floor. Unoxidized pyrrhotite-rich massive-sulfide samples were obtained from the flanks of one of these volcanic centers. The composition and form of the sulfide samples suggest significant interaction between hydrothermal fluids and sediment at depth, and deposition of sulfide within the sediment pile.
Becoming Certified in “Leadiatrics”: What Every Pediatrician Needs to Do

When I learned I was the recipient of this year’s Joseph W. St Geme Jr Award, I was honored, to say the least, and for a while at a loss for written or spoken words, which for those who know me is highly unusual. It is humbling to be considered in the same category as previous awardees and as someone who exemplifies what Dr St Geme strove for in his own life as a leader, consensus builder, unifier, and collaborator. In thinking about receiving this award and how I might reflect on the values and attributes of Dr St Geme, I wondered what he might say about the world in which we live today. Instead of consensus building, in 2014 we live in a world of silos, meaning more and more aspects of pediatrics are becoming stand-alone towers that seem unable to connect with one another. There are certainly the silos we are familiar with in medical education—undergraduate, graduate, and continuing medical education, and new ones like maintenance of certification—all hoping to join together, but each with their own curriculum, standards, and assessments. Clinical care has also become increasingly more fragmented. Think of the many pediatric subspecialties that exist today, each with their own set of boards and requirements, and the new ones being developed, such as general academic pediatrics and hospitalist medicine, which are now striving to be recognized as separate board-certifiable fields when they had not until recently been considered as such. In addition to clinical pediatrics, research has also become more siloed. Just how specialized has our field of pediatric research become? Just look at the program for this past year’s Pediatric Academic Societies (PAS) meeting, and it’s no longer a simple listing of papers and posters on neonatology. Instead you can select your area of interest … Address correspondence to Lewis R. First, MD, UVM, Department of Pediatrics, Given Courtyard, S250, Burlington, VT 05405. E-mail: lewis.first{at}uvm.edu
Fungal peritonitis caused by Curvularia species in a child undergoing peritoneal dialysis.

We report the first case of peritonitis caused by Curvularia species in a child undergoing peritoneal dialysis. He presented with gray-black proteinaceous material obstructing the lumen of his Tenckhoff catheter. Although the peritoneal fluid was cloudy, the patient suffered neither significant abdominal tenderness nor systemic symptoms. Catheter removal and treatment with amphotericin B allowed complete recovery and return to peritoneal dialysis within 7 days. Outdoor play in a wooded environment may have allowed contact of this saprophytic fungus with the child’s indwelling catheter transfer set.
Assessment of infrazygomatic bone depth for mini‐screw insertion

Objective: To investigate the bone depth at the infrazygomatic crest with regard to orthodontic mini-screw insertion. Material and methods: Twenty-nine adult human dry skulls were imaged using CBCT technology, slice data were generated and multiple measurements were undertaken at three sites associated with the infrazygomatic crest and five different measurement levels. The data were analyzed using intraclass correlation and repeated measures ANOVA. Results: The greatest bone depth was available at, on average, 11.48±1.92 mm apical from the cemento-enamel junction of the maxillary first molar and decreased rapidly further apically. Maximum bone depth (7.05±3.7 mm) was present at the lowest measurement level. However, here, insufficient clearance to the molar roots was present. Both the measurement site and the level at which the measurements were conducted had a significant impact on bone depth. Conclusions: When inserting orthodontic mini-screws (6 mm or longer) into the infrazygomatic crest while staying clear of the molar roots perforation of the maxillary sinus or the nasal cavity can be expected, but bone depth varies considerably between individuals.
Context-dependent computation by recurrent dynamics in prefrontal cortex

Prefrontal cortex is thought to have a fundamental role in flexible, context-dependent behaviour, but the exact nature of the computations underlying this role remains largely unknown. In particular, individual prefrontal neurons often generate remarkably complex responses that defy deep understanding of their contribution to behaviour. Here we study prefrontal cortex activity in macaque monkeys trained to flexibly select and integrate noisy sensory inputs towards a choice. We find that the observed complexity and functional roles of single neurons are readily understood in the framework of a dynamical process unfolding at the level of the population. The population dynamics can be reproduced by a trained recurrent neural network, which suggests a previously unknown mechanism for selection and integration of task-relevant inputs. This mechanism indicates that selection and integration are two aspects of a single dynamical process unfolding within the same prefrontal circuits, and potentially provides a novel, general framework for understanding context-dependent computations.
An analysis of the bulging of a superplastic sheet by lateral pressure

Abstract An analysis is presented for the bulging by lateral pressure of superplastic alloy sheet that has a flow equation, in uniaxial tension or compression, given by σ = K e m , where σ is the flow stress, e the strain rate and K and m are material parameters. Two cases are dealt with: (1) the bulging of a flat circular sheet clamped at its perimeter and (2) the bulging of a sheet into 90° V grooves. The latter process is pertinent to the problem of molding a sheet to a die contour so as to achieve detail. Bulge profile and sheet thickness distribution are predicted as a function of the variables of pressure, geometry, time, K and m . Results are in good agreement with experimental findings.
Spin–valley phase diagram of the two-dimensional metal–insulator transition

The metallic behaviour of the resistivity observed at low temperatures in low-disorder, dilute, two-dimensional (2D) carrier systems is of considerable interest as it defies the scaling theory of localization in two dimensions1. Although the origin of the metallic behaviour remains unknown and controversial, there is widespread evidence that the spin degree of the freedom plays a crucial role. Here, we directly probe the role of another discrete electronic degree of freedom, namely the valley polarization. Using symmetry-breaking strain together with an in-plane magnetic field to tune the valley and spin polarizations of an AlAs 2D electron system at fixed density, we map out a spin–valley phase diagram for its metal–insulator transition. The insulating phase occurs in the quadrant where the system is sufficiently spin and valley polarized. This observation establishes the equivalent roles of spin and valley degrees of freedom in the 2D metal–insulator transition.
Statistical model for fragmentation of C 60

A simple statistical model is formulated to predict inclusive distributions and correlations of fragments from highly excited ${\mathrm{C}}_{60}.$ Sequential decay of excited fragments produced in an initial binary fragmentation are taken into account. A qualitative account of results from a recent experiment is achieved.
Who is responsible for evaluating the safety and effectiveness of medical devices? The role of independent technology assessment.

Introduction The global medical technology industry brings thousands of devices to market every year. However, significant gaps persist in the scientific literature, in the medical device approval process, and in the realm of postmarketing surveillance. Although thousands of drugs obtain approval only after review in randomized controlled trials, relatively few new medical devices are subject to comparable scrutiny.
Guided waves for SHM of a large truss structure

This paper describes a method based on Ultrasonic Guided Waves (UGWs) for the detection of cracks in sign support structures. The method combines the advantages of UGWs with the extraction of defect-sensitive features aimed at performing a multivariate diagnosis of damage. The general frame work presented in this paper is applied to ultrasonic data collected from a dimantled overhead sign support structure tested at the University of Pittsburgh. The probing hardware consists of a National Instruments-PXI platform that controls the generation and detection of the ultrasonic signals by means of the piezoelectric transducers made of Lead Zirconate Titanate. The effectiveness of the proposed approach to diagnose the presence of defects as small as a few percent of the waveguide cross-sectional are is demonstrated.
High-throughput Fabrication of Nanoplasmonic Devices for SPR and SERS Biosensing

We will present high-throughput fabrication techniques for nanoplasmonic devices, including template stripping, nanoimprinting, and interference lithography. Then we will discuss how to combine nanoplasmonic sensors with free-space optics and microfluidics to construct high-performance biosensing instruments. Article not available.
Parity nonconservation in Tl and Bi atoms

In connection with experiments which have been carried out and are planned, we have calculated the violation of parity conservation due to neutral weak currents for transitions to the first excited states of $^{205}\mathrm{Tl}$ and $^{209}\mathrm{Bi}$. A Green's-function technique is used to evaluate the parity-nonconserving transition matrix. The dependence of the results on various input data (e.g., the Weinberg angle) is discussed.
Clustering of noisy image data using an adaptive neuro-fuzzy system

Identification of outliers or noise in a real data set is often quite difficult. A recently developed adaptive fuzzy leader clustering (AFLC) algorithm has been modified to separate the outliers from real data sets while finding the clusters within the data sets. The capability of this modified AFLC algorithm to identify the outliers in a number of real data sets indicates the potential strength of this algorithm in correct classification of noisy real data.
Effect of the Jovian oblateness on Pioneer 10/11 radio occultations

The oblateness of Jupiter, which was neglected in the standard inversion technique for radio occultation data, has a substantial effect on the refractivity profiles of the neutral Jovian atmosphere derived from the Pioneer 10/11 occultations. The geometry of the Pioneer 10 entry and exit occultations has the effect that oblateness should account for much of the discrepancy of the results with plausible atmospheric models. The effect of the oblateness on Pioneer 11 entry is smaller, where much of the discrepancy could be due to other effects, such as cycle-slip in the spacecraft transponder. Theory indicates that the Pioneer 11 exit occultation should be affected by the oblateness in the opposite sense from the first three occultations; and, indeed, the data which had not been invertible under the spherical assumption produced reasonable results when an oblateness correction was applied.
Suppression of malaria infection by oxidant-sensitive host erythrocytes

DEFICIENCY of the red cell enzyme, glucose-6-phosphate dehydrogenase (G-6-PD), predisposes erythrocytes to oxidant-induced haemolysis and is thought to protect humans against severe malaria infection. We have already shown that the malaria parasite exerts an oxidant stress on infected red cells and suggested that premature lysis of malaria infected erythrocytes might occur in G-6-PD deficient humans1, thus limiting the severity of infection by enforcing the release of immature parasites incapable of propagating the infection2.
Popular Responsiveness to Taxation

In this article we conduct an examination of voter sensitivity to levels of state taxation by developing and testing models that emphasize the infor mation costs associated with taxation issues. We are able to demonstrate, in some contrast to previous studies, that mass opinion about taxation has systematic and predictable components. Hostility to state taxes is found to vary systematically with actual tax levels. We also demonstrate that voters are able to link opinions on taxes to opinions of government performance.
Oral Narrative Skills of Chilean Preschool Children

The purpose of this study was to analyze oral narrative discourse in Chilean preschool children using High Point Analysis and Narrative Assessment Profile in a cross-sectional study of monolingual Spanish speakers, and to establish the relationships between oral narrative discourse development and emergent literacy skills. Participants were 94 4- to 6-year-old low-income children. Both narrative analyses were consistent and reliable measures of oral narrative skills of Chilean children. Sequence of events, Informativeness, and Topic Maintenance are the most consistent categories of NAP. The Woodcock-Munoz language battery was also administered, and the sub-scales of the test that significantly positively correlated to NAP and HP were Picture Vocabulary and Understanding Directions. WoodcockMunoz’s sub-scales Letter-Word Identification, Spelling, and Passage Comprehension obtained lower correlations to NAP and HP, which might suggest that the abilities they measure (reading decoding, spelling ability, and reading comprehension, respectively) may not be closely related to oral narrative skills or that their relationship may appear later in life.
Structural damage to the corticospinal tract correlates with bilateral sensorimotor cortex reorganization in stroke patients

Damage to the corticospinal tract (CST) in stroke patients has been associated with functional reorganization in the ipsilesional and contralesional sensorimotor cortices. However, it is unknown whether a quantitative relationship exists between the extent of structural damage to the CST and functional reorganization in stroke patients. The purpose of the current study was to examine the relationship between structural CST damage and motor task-related cortical activity in chronic hemiparetic stroke patients. In 10 chronic hemiparetic stroke patients with heterogeneous lesions, CST damage was quantified using conventional structural magnetic resonance imaging and tractography based on diffusion tensor imaging. Cortical activity was measured using functional magnetic resonance imaging during repetitive flexion/extension movements of the digits. We found that the two measures of CST damage were strongly correlated. Moreover, greater CST damage was significantly and linearly correlated with increased activation during affected hand movement in the hand area of the contralesional primary sensorimotor cortex (M1/S1) and in the ipsilesional M1/S1 ventral to the hand area. To our knowledge, this is the first demonstration of a quantitative relationship between the extent of structural damage to the CST and functional reorganization in stroke patients. This relationship was observed in stroke patients with heterogeneous lesions, suggesting that CST damage is a factor relevant to the variation in functional reorganization in the clinical population.
Serum lipoproteins, lipid peroxides and prostacyclin biosynthesis in patients with coronary hear diseases

Abstract Serum low-density lipoproteins (LDL)_and high-density lipoproteins (HDL) were prepared by gradient ultracentrifugation and dialysis from 12 healthy subjects and 15 patients with coronary heart disease and hyperlipoproteinemia. In both lipoprotein fractions cholesterol and lipid peroxides were determined. The effect of these lipoproteins on spontaneous prostacyclin biosynthesis in rat aortic slices was studied. Serum lipoproteins were susceptible to peroxidation during the preparation procedure. LDL were more prone to peroxidation than HDL. Little lipid peroxidase were formed in lipoproteins when calcium ions had been removed by EDTA, and when butylated hydroxytoluene (BHT) was present at all stages of their preparation. LDL when prepared without these precautions either from healthy subjects or from patients with coronary heart diseases markedly suppressed prostacyclin generation by rat aortic slices. This inhibition to LDL-lipid peroxides. Peroxide-low LDL prepared from most of the healthy subjects and patients with coronary heart disease and concomitant hyperlipoproteinemia, did not inhibit prostacyclin biosynthesis. However, in one quarter of the patients. LDL was inhibitory. Consequently, in some patients with coronary heart disease, there operate unknown mechanisms which are responsible for the inhbibitory activity of LDL on prosctacylin generation.
Second-order numerical advection

Abstract A second order accurate numerical approximation to the advection terms in the primitive equations of hydrodynamics is proposed. The scheme is compared with a similar second-order scheme and a first-order scheme in view of aliasing effects and of amplitude and phase errors. A stability criterion is derived for the one-dimensional case and one is suggested for the two-dimensional case. Numerical results from simple test calculations are given.
Density of states and finite size scaling investigations

Abstract Monte Carlo simulations are performed to calculate the density of states on L D block lattices, and high precision estimates for the leading partition function zeros are obtained. With the help of a finite size scaling analysis one can look for the critical exponent v , and investigate the behaviour of the maximum of the specific heat. Results are presented for 2D 10-state Potts and 3D 3-state Potts models.
Characteristics of band-limited channels unidentifiable from second-order cyclostationary statistics

Several works on blind channel identification and equalization rely on a system model with multiple sub-channels driven by a single input. These methods depend on a critical condition that no common zero exists among the sub-channels. We aimed at establishing the physical significance of this critical zero condition and understanding the limitation of methods based on second-order statistics, By deriving a number of sufficient conditions, we characterize several classes of band-limited channels that are not identifiable from only the second-order statistics of the channel output.
Non-linear dynamics method for target identification

One may describe the effect of a radar or sonar target on an incoming signal as a filter that produces a scattered signal. Chaotic signals are very sensitive to the effect of filters, and so a radar or sonar target imposes a unique signature on a scattered chaotic signal. In this study the authors describe a method that uses the concept of phase space dimension to create a reference from a scattered chaotic signal. This reference becomes part of a library, and comparing an unknown scattered signal to this library can reveal which target caused a particular scattered signal. As the authors are not imaging the target, this method can use signal with low-range resolution.
Chalcogenide glass 1D photonic bandgap hollow fiber

ABSTRACT We propose a chalcogenide glass 1-D photonic bandgap (PBG) hollow fiber for the transmission of mid-IR radiation. Its structure consists of an air-core surrounded by alternating rings of high and low refractive index chalcogenide glass supported by a thick polymer coating. Theoretical calculations demonstrate the potential to achieve low transmission losses at 10.6 µ m for the HE 11 mode. These calculations indicate that the chalcogenide glasses used in the PBG structure should have high index contrast and low extinction coefficients to minimize transmission losses. We present preliminary results of our ongoing efforts to identify a pair of chalcogenide glasses that meet this criterion. A strategy is developed for the fabrication of a drawable chalcogenide glass 1-D PBG hollow fiber preform. Keywords: hollow infrared waveguides, photonic bandgap, Bragg fiber, chalcogenide glass 1. INTRODUCTION Hollow core infrared (IR) waveguides are an attractive alternative to solid core fibers because they have low transmission losses and can transmit significant power. An example of a hollow core IR waveguide is the hollow glass waveguide
Heads and tails: studies of web search with common and rare queries

A large fraction of queries submitted to Web search enginesoccur very infrequently. We describe search log studiesaimed at elucidating behaviors associated with rare andcommon queries. We present several analyses and discussresearch directions.
EFFECT OF THREE KINDS OF KNOWLEDGE-OF-RESULTS INFORMATION ON THREE MEASURES OF VIGILANCE PERFORMANCE.

Tea Ss in each of 8 groups individually performed a watchkeeping task of 1 hr. duration. Each group was presented one of the 8 factorial combinations of the presence (or absence) of 3 different kinds of knowledge of results (KR), i.e., KR regarding missed signals, correctly detected signals, and false responses. The results indicated that KR regarding missed signals produced a significant decrease in the total number of false responses, and that KR regarding correct detections produced a significant decrease in the proportion of missed signals. When KR regarding false responses was given, there was both a significant increase in reaction time to correct detections and a significant decrease in the number of false responses. In short, the effect of providing a specific type of information in a watchkeeping task appears to be specific to the measure of performance efficiency employed. A discussion is included of the interpretation of these results.
Searching the Sinus Amoris: Using profiles of geological units, impact and volcanic features to characterize a major terrane interface on the Moon

Geochemical profiles of surface units, impact, and volcanic features are studied in detail to determine the underlying structure in an area of extensive mare/highland interface, Sinus Amoris. This study region includes and surrounds the northeastern embayment of Mare Tranquillitatis. The concentrations of two major rock-forming elements (Mg and Al), which were derived from the Apollo 15 orbital geochemical measurements, were used in this study. Mapped units and deposits associated with craters in the northwestern part of the region tend to have correlated low Mg and Al concentrations, indicating the presence of KREEP-enriched basalt. Found along the northeastern rim of Tranquillitatis were areas with correlated high Mg and Al concentration, indicating the presence of troctolite. Distinctive west/east and north/south trends were observed in the concentrations of Mg and Al, and, by implication, in the distribution of major rock components on the surface. Evidence for a systematic geochemical transition in highland or basin-forming units may be observed here in the form of distinctive differences in chemistry in otherwise similar units in the western and eastern portions of the study region.
Manipulation of objects in a captive group of lion-tailed macaques (Macaca silenus).

The purpose of this study was to investigate the manipulative propensities of a captive group of lion-tailed macaques (Macaca silenus). Simple natural objects (browse and bamboo poles) were provided regularly in the home cage. Findings indicate richness in the frequency and form of manipulative activities, with juvenile males manipulating the test objects more frequently and exhibiting more goal-directed manipulative activity than adult females. A variety of goal-directed manipulative activities (use of objects to act as ladders, to apply leverage, and to create perches) occurred spontaneously, with some instances involving joint action or social use. These data are consistent with the hypotheses that macaques possess extensive capacities for object exploration and social facilitation, and that an evolutionary history of omnivorous foraging habits correlates positively with the expression of anomalous sensorimotor skills.
Spatial genetic structure of delphinium nuttallianum populations: inferences about gene flow

The spatial genetic structure of a plant population provides a potential record of past gene flow and mating. We used hierarchical F-statistics and spatial autocorrelation to characterize spatial genetic differentiation of allozymes in adult Delphinium nuttallianum plants within and among six natural populations separated from one another by up to 3 km. Previous direct estimates suggested that gene flow is highly localized, averaging 100 m). Thus we anticipated substantial genetic differentiation on scales of a few to hundreds of metres. However, we detected little differentiation among the six populations, among replicate study plots within populations, or among subsections of study plots, except at the smallest scale of cm to m. These results suggest that relatively rare long-distance pollen movement has gone undetected and that postpollination selection may further modify genetic structure during the life cycle. Lack of differentiation is not at odds with the observation of partial reproductive isolation, because some loci may respond to spatial variation in selection without this response being evident at marker loci.
Aggressive behavior and anaplasia in pleomorphic xanthoastrocytoma: a plea for a revision of the current WHO classification

SUMMARY: Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic neoplasm that commonly affects children and young adults, and presents with seizures. PXA is typically supratentorial with a predilection to the temporal lobe, and often involves the cortex and the meninges. PXAs have a favorable prognosis with a 10-year survival probability of >70%, and are WHO grade II neoplasms. Recent observations and studies demonstrate that PXAs are clinically, histologically and genetically distinct. Some PXAs recur and exhibit aggressive clinical behavior. In such cases, certain histological and clinical factors could account for the aggressive behavior. However, the histological features that predict adverse outcome are poorly defined. In the current WHO classification of CNS tumors, there is no option for a high-grade PXA, even if the tumor had numerous recurrences and poor outcome. In this review, we focus on aggressive clinical behavior and anaplasia in PXA, and discuss how our current experience suggests modifi...
Effects of acetic acid and hydrogen peroxide application during defeathering on the microbiological quality of broiler carcasses prior to evisceration

The microbiological quality and skin appearance of New York dressed broiler carcasses were determined in two separate experiments after a water control, acetic acid, or H2O2 spray during defeathering. Broilers were picked up from a local processor and transported in coops to the pilot facility. In both experiments, commercial processing parameters were followed up to the defeathering step. After feather removal, the vents of all carcasses were blocked with a cotton plug to prevent contamination of the whole carcass rinse diluent with fecal material from the lower gut. The neck and feet were removed, and the carcasses were placed in individual plastic bags in preparation for a whole carcass rinse. Results showed a statistically significant reduction (P < 0.05) in the log10 total aerobic plate counts for carcasses treated with 1% acetic acid in comparison to the water control (log10 cfu counts = 3.93 and 4.53, respectively). No differences were observed in skin appearance due to the 1% acid treatment. The addition of 0.5, 1, or 1.5% H2O2 to spray waters had no effect on microbiological quality of the carcasses when compared to the water control (4.92, 5.01, 4.91, and 4.99 log10 counts, respectively). The skin of carcasses treated with hydrogen peroxide, regardless of the concentration was bleached and bloated.
Ideal Bose Gas in Fractal Dimensions

We extended the three dimensional ideal Bose gas theory into the fractal dimensions between 2 and 3. The thermodynamic properties and critical exponents of the ideal Bose gas are studied through the functional analysis of the Bose gas function in the fractal dimensions. The condensation and phase transition of the ideal system depend on its dimensions. The phase transition is detectable only in the sufficiently high derivatives of the specific heat function. The derivatives change discontinuously at values of the fractal dimensions which we have calculated.
Nanotechnology Enables Wireless Gas Sensing

In this paper different topologies of CNT-based RF passive gas sensors are presented, particularly focusing on wireless transducers, which can directly indicate gas concentration through the change of easy to-monitor RF parameters. CNTs feature numerous unique properties that could potentially enable the next generation of gas sensors with sensitivities better by 1-2 orders of magnitude with respect to existing ones.