cssi/SciSciGPT-SciSciNet huggingface dataset:
For more-than-usefulness: Six overlapping points about Children's Geographies

A number of recent Children's Geographies articles (Catan, 2003; Cunningham, 2003; Karsten, 2003; Cahill, 2004; Pain, 2004; Smith, 2004; Vanderbeck and Morse Dunkley, 2004) might be caricatured as ...
Formation of ultracold 7Li85Rb molecules in the lowest triplet electronic state by photoassociation and their detection by ionization spectroscopy

We report the formation of ultracold 7Li85Rb molecules in the a3Σ+ electronic state by photoassociation (PA) and their detection via resonantly enhanced multiphoton ionization (REMPI). With our dual-species Li and Rb magneto-optical trap apparatus, we detect PA resonances with binding energies up to ∼62 cm−1 below the 7Li 2s 2S1/2 + 85Rb 5p 2P1/2 asymptote. In addition, we use REMPI spectroscopy to probe the a3Σ+ state and excited electronic 33Π and 43Σ+ states and identify a3Σ+ (v″ = 7–13), 33Π (vΠ′ = 0–10), and 43Σ+ (vΣ′ = 0–5) vibrational levels. Our line assignments agree well with ab initio calculations. These preliminary spectroscopic studies on previously unobserved electronic states are crucial to discovering transition pathways for transferring ultracold LiRb molecules created via PA to deeply bound rovibrational levels of the electronic ground state.
Simultaneous accumulations of naphthalene, a PCB mixture, and benzo(a)pyrene, by the oyster,Crassostrea virginica

The objective of the present investigation was to assess accumulations or ogranic contaminants when the oyster Crassostrea virginica was simultaneously exposed to several contaminants. Polychlorinated biphenyls (PCBs), naphthalene, and benzo(a)pyrene were selected for study due to their toxicity and ubiquitous distribution in the marine environment. The objective included considering the possible significance of contaminant accumulations to humans by using a commercially important organism, and possible antagonistic-synergistic effects of multiple contaminants. The bioavailability of contaminants presented as dissolved versus particulate matter was also investigated.
Oxidation of 3-hydroxykynurenine to produce xanthommatin for eye pigmentation: a major branch pathway of tryptophan catabolism during pupal development in the Yellow Fever Mosquito, Aedes aegypti

This study concerns the metabolic pathways of 3-hydroxykynurenine in Aedes aegypti mosquitoes during development with emphasis on its oxidation pathway to produce xanthommatin during eye pigmentation. Oxidation of tryptophan to 3-hydroxykynurenine is the major pathway of tryptophan catabolism in Aedes aegypti, but 3-hydroxykynurenine oxidizes easily under physiological conditions, which stimulate the production of reactive oxygen species. Our data show that in Aedes aegypti, the chemically reactive 3-hydroxykynurenine is converted to the chemically stable xanthurenic acid by a transaminase-catalyzed reaction during larval development, while 3-hydroxykynurenine is transported to the compound eyes for eye pigmentation during pupal development. Our data suggest that (1) the transamination pathway of 3-hydroxykynurenine is down-regulated during the pupal development, (2) 3-hydroxykynurenine produced in other body tissues is actively transported to the compound eyes during the pupal stage, (3) the compound eye is the place where ommochromes are produced, and (4) formation of ommochromes results from nonenzymatic oxidation of 3-hydroxykynurenine in the compound eyes.
A Prospective Study of Mitral Valvular Prolapse in Young Men

A cardiac history, a physical examination, an electrocardiogram, phonocardiograms in the supine and standing positions, and an M-mode echocardiogram were obtained in 100 randomly selected, presumably healthy, male medical students (mean age, 26 years). Four percent met standard echocardiographic criteria for mitral valvular prolapse. No midsystolic clicks or late systolic murmurs were appreciated in this group, and none complained of chest pain or palpitations. To elucidate further the clinical implications of the echocardiographic pattern of mitral valvular prolapse, 24-hour ambulatory ECGs, multistage exercise tests, and scintiscans of myocardial perfusion at rest and after exercise (using radioactive 13 nitrogen-labelled ammonium) were obtained, with normal results. The absence of life-threatening arrhythmias and exercise-induced abnormalities in these four asymptomatic subjects without abnormal physical findings suggests that the echocardiographic pattern of mitral valvular prolapse in such individuals may represent a variant of normal which does not require extensive evaluation.
The relation of symptoms to osteoarthritis.

Abstract 1. 1. Morning stiffness and x-ray evidence of osteoarthritis do not show evidence of association in this population study. 2. 2. Only about 30 per cent of persons with radiologtic evidence of de generative changes in their joints complained of pain at the relevant sites. 3. 3. Pain and swelling in osteoarthritic joints are seldom found wdithout morning stiffness. The exception to this course is found in the acute Heberden's node. It should b e remembered in this connection that one inquiry about morning stiffness is often insufficient to pick up this manifestation. 4. 4. Persons with x-ray evidence of osteoarthritis but no morning stiffness have only a small chance of having pain at the relevant sites. 5. 5. The importance of distinguishing symptomatic and asymptomatic oesteoarthritis has been emphasized and the difference in symptom pattern between those with morning stiffness and the relatively few without it has been presented. 6. 6. The possibility that most of the symptoms of “osteoarthritis” are at least in part due to a rheumatoid component has been discussed.
The DrrC protein of Streptomyces peucetius, a UvrA‐like protein, is a DNA‐binding protein whose gene is induced by daunorubicin

DrrC, a daunorubicin resistance protein with a strong sequence similarity to the UvrA protein involved in excision repair of DNA, is induced by daunorubicin in Streptomyces peucetius and behaves like an ATP-dependent, DNA binding protein in vitro. The refolded protein obtained from expression of the drrC gene in Escherichia coli was used to conduct gel retardation assays. DrrC bound a DNA segment containing the promoter region of a daunorubicin production gene only in the presence of ATP and daunorubicin. This result suggests that DrrC is a novel type of drug self-resistance protein with DNA binding properties like those of UvrA. Western blotting analysis with a polyclonal antiserum generated against His-tagged DrrC showed that the appearance of DrrC in S. peucetius is coincident with the onset of daunorubicin production and that the drrC gene is induced by daunorubicin. These data also showed that the DnrN and DnrI regulatory proteins are required for drrC expression. The level of DrrA, another daunorubicin resistance protein that resembles ATP-dependent bacterial antiporters, was regulated in the same way as that of DrrC.
Learned resistance to punishment and subsequent responsiveness to the same and novel punishments

In a factorial study, rats were trained to approach and consume food in the presence of gradually increasing shock punishment, gradually increasing airblast punishment, or no punishment, and were subsequently tested with full-strength shock of airblast punishment. The results showed that rats could learn to resist intense shock or airblast punishment if they were introduced gradually. While Ss learning to resist shock showed an increased resistance to airblast there was no evidence of the corresponding generalization from airblast to shock.
Non-radioactive electron-capture detector for gas chromatography

Abstract This paper is an update on the progress made towards developing a practical electron-capture detector which does not require a radioactive source, can be operated in the pulsed mode, and can be used at temperatures up to 800 K. Data obtained using a prototype detector have been reported previously. In this paper results obtained with a “large-volume” but leak-free detector at elevated temperatures are reported, and preliminary data with a practical “small-volume” detector will be discussed. The temperature dependence suggests that the electron-capture mechanisms that have been demonstrated previously are also operative in the non-radioactive detector. The discharge has been examined spectroscopically. Finally, we present characteristic data for the detector under high-purity conditions. These data are similar to those obtained with a radioactive detector and serve as a “base case” for future development.
Polymer reference interaction site model theory: New molecular closures for phase separating fluids and alloys

The polymer reference interaction site model integral equation theory when combined with known atomic‐like closure approximations is shown to be qualitatively inconsistent with classical mean field predictions for both long wavelength concentration fluctuations and the molecular weight dependence of the critical temperature of binary polymer blends. The fundamental error is shown to arise from the failure of atomic‐like closures to explicitly account for strong correlations between the segments on two interpenetrating polymer coils which are close in space but widely separated in chemical sequence. A family of new ‘‘molecular’’ closures are formulated which explicitly account for chemical‐bonding mediated correlations. These new closures are all qualitatively consistent with mean field scaling of the critical temperature with chain length. A detailed analytical derivation of the predictions of the new closures for thread‐like symmetric blends is carried out, and the influence of density and concentration ...
Novel Amphiphilic Phthalocyanines: Formation of Langmuir−Blodgett and Cast Thin Films

The synthesis and solution and thin film characterization of four octasubstituted phthalocyanines (Pcs) are reported. [2,3,9,10,16,17,23,24-octakis(dodecylcarboxylato)phthalocyaninato]copper, [2,3,...
Relation of successive percentiles of reaction time distributions to cognitive variables and adult age

Abstract The reaction time distributions for each individual in a moderately large sample of adults were analyzed in terms of percentiles, and then each reaction time percentile was correlated with a number of cognitive variables and with age. A very similar pattern was evident across five sets of reaction time tasks. This consisted of the correlations with the cognitive variables remaining stable, but those with adult age decreasing, from the fastest to the slowest responses emitted by the individual. Contrary to recent reports (Kranzler, 1992; Larson & Alderton, 1990), these results suggest that all portions of the reaction time distribution contain qualitatively similar individual difference information.
Inhibition of cell migration and angiogenesis by the amino terminal fragment of 24kD basic fibroblast growth factor

Abstract The 24-kDa form of basic fibroblast growth factor inhibits the migration of endothelial cells and mammary carcinoma cells while continuing to promote cell proliferation. This molecule consists of the 18-kDa fibroblast growth factor sequence plus an additional 55 amino acids at the amino-terminal end. Antibody neutralization studies suggested that the inhibition of migration is associated with these 55 amino acids, whereas the promotion of proliferation localizes to the 18-kDa domain. To determine whether 24kD basic fibroblast growth factor could be modified to eliminate its effect on cell proliferation but retain its inhibition of migration, portions of the carboxyl-terminal end of 24kD fibroblast growth factor were deleted, and the products were tested on MCF-7 and endothelial cells. A protein consisting of the 55 amino acids of the amino-terminal end and the first 31 amino acids of 18kD basic fibroblast growth factor (ATE+31) inhibited migration by 80% but did not promote cell growth. Arginine to alanine substitutions within the first 21 amino acids of the carboxyl-terminal end substantially reduced the efficacy of ATE+31, whereas substitutions in the remaining part of the molecule had no effect. Competition binding experiments showed that ATE+31 does not compete with 24kD basic fibroblast growth factor for binding to fibroblast growth factor receptor 1. In an in vivo matrigel plug assay, 150 nm ATE+31 peptide reduced angiogenesis by 80%. These studies demonstrate that the amino-terminal end of 24kD basic fibroblast growth factor is responsible for an activity that inhibits the migration rates of cultured cells as well as the angiogenic response in vivo.
Exposure to select phthalates and phenols through use of personal care products among Californian adults and their children

Introduction Certain phenols and phthalates are used in many consumer products including personal care products (PCPs).
Morphology characterization of polyaniline nano- and microstructures

Small-angle neutron scattering (SANS), nuclear magnetic resonance (NMR), wide-angle and small-angle X-ray scattering (WAXS and SAXS) measurements were carried out to investigate the three morphological forms of polyaniline emeraldine base (PANI-EB): unstructured, microtubes, and nanofibers. Although the chemical backbone between these two materials is quite similar, their solid structures are quite different, showing differences in the molecular conformation and supramolecular packing. Detailed solid-state 13C and 15N NMR characterization of PANI nanofibers (compared to the unstructured, granular form) revealed a slight variation in the structural features of the polymer that led to some differences in the chemical environments of the respective nuclei. The presence of two extra-sharp peaks at 96.5 and 179.8 ppm is a distinct feature found exclusively in the nanofiber spectra. Moreover, the crosspolarization (CP) dynamics study disclosed the presence of a complete set of sharp NMR peaks that are responsible for the presence of a more ordered morphology in the nanofiber. Small-angle neutron scattering indicated very sharp interfaces in the PANI fibers, which are well organized and have extremely sharp domains within the length scales probed (not, vert, similar10–1 nm). Overall, the X-ray scattering and spectroscopy data suggest that the nanofiber form is structurally different from the unstructured, PANI-EB powder. These differences are manifested, in part, by the additional chemistry occurring during the synthesis of the nanofibers.
Cyclic creep of Al-4.6% Mg at moderate temperatures

Abstract Creep in Al - 4.6% Mg in the temperature range of 324 to 360 K has been investigated as a function of the applied stress function. Comparisons of properties are made between samples crept at a constant applied load (referred to as static creep) and samples crept with a varying tensile load (referred to as cyclic creep) such that the peak load is equal to the load applied statically. The average creep rates in cyclic creep were equal to or greater than the corresponding values for static creep even though the average stress was lower. Analysis of the activation energies and stress dependencies for static and cyclic creep revealed similar properties. The enhanced creep rates due to cyclic stressing are explained by recovery effects which occur during the low portion of each stress cycle.
Data management and analysis for the Earth System Grid

The international climate community is expected to generate hundreds of petabytes of simulation data within the next five to seven years. This data must be accessed and analyzed by thousands of analysts worldwide in order to provide accurate and timely estimates of the likely impact of climate change on physical, biological, and human systems. Climate change is thus not only a scientific challenge of the first order but also a major technological challenge. In order to address this technological challenge, the Earth System Grid Center for Enabling Technologies (ESG-CET) has been established within the U.S. Department of Energy's Scientific Discovery through Advanced Computing (SciDAC)-2 program, with support from the offices of Advanced Scientific Computing Research and Biological and Environmental Research. ESG-CET's mission is to provide climate researchers worldwide with access to the data, information, models, analysis tools, and computational capabilities required to make sense of enormous climate simulation datasets. Its specific goals are to (1) make data more useful to climate researchers by developing Grid technology that enhances data usability; (2) meet specific distributed database, data access, and data movement needs of national and international climate projects; (3) provide a universal and secure web-based data access portal for broad multi-model data collections; and (4) provide a wide-range of Grid-enabled climate data analysis tools and diagnostic methods to international climate centers and U.S. government agencies. Building on the successes of the previous Earth System Grid (ESG) project, which has enabled thousands of researchers to access tens of terabytes of data from a small number of ESG sites, ESG-CET is working to integrate a far larger number of distributed data providers, high-bandwidth wide-area networks, and remote computers in a highly collaborative problem-solving environment.
LIBS controls characterization of predictor corrector-based LIBS data collection

Portable LIBS sensor communication bandwidth limitations favor local material classification for low power consumption. Partial Least Squares - Discriminant Analysis (PLS-DA) and Principle Component Analysis (PCA) have been implementation via general purpose computers and are accepted for some Department of Defense applications. Prior publications address the creation of a low mass, low power, robust hardware spectra classifier for a limited set of predetermined materials in an atmospheric matrix. The incorporation of a PCA or a PLS-DA classifier into a predictorcorrector implementation on a TI6701 has been developed. The performance modeling of the control system with an emphasis on further optimization needs addressing. This paper characterizes, from a control system standpoint, the predictor-corrector architecture applied to LIBS data collection. In addition, the application of this as a material classifier is presented. Updates in the model implemented on a low power multi-core DSP will be presented as well. Performance comparisons to alternative control system structures will be considered.
Antiserum against rat luteinizing hormone (LH) receptors

Summary An antiserum to soluble rat luteal LH receptors was produced in rabbits. The presence of LH receptor antibodies was shown by indirect immuno-precipitation of [125]hCG-soluble rat LH receptor-receptor antiserum complexes by antirabbit IgG. The antiserum bound LH receptors from rat ovaries and testes but not those from human or sheep ovaries. Unoccupied LH receptors competed with [125I]hCG occupied receptors in a dose-dependent fashion for antiserum binding. Extracts of rat brain and liver did not appear to bind to the antiserum. In addition, LH-dependent progesterone secretion from isolated rat ovarian cells was reduced by the antiserum although there was no change in hormone binding.
UNIFORMLY ACCELERATING CHARGED MASS IN GENERAL RELATIVITY.

We discuss a type-{22} solution of the Einstein-Maxwell equations which represents the field of a uniformly accelerating charged point mass. It contains three arbitrary parameters $m$, $e$, and $A$, representing mass, charge, and acceleration, respectively. The solution is a direct generalization of the Reissner-Nordstrom solution of general relativity and the Born solution of classical electrodynamics. The external "mechanical" force necessary to produce the acceleration appears in the form of a timelike nodal two-surface extending from the particle's world line to infinity. This does not prevent us from regarding the solution as asymptotically flat and calculating the radiation pattern of its electromagnetic and gravitational waves. We find as well a maximal analytic extension of the solution and discuss its properties. Except for an extra "outer" Killing horizon due to the accelerated motion, the horizon structure closely resembles the Reissner-Nordstrom case.
Wavefront sensing with the differential optical transfer function

Recently a new technique for estimating the complex field in the pupil of a telescope from image-plane intensity measurements has been introduced by Codona.1, 2 The simplest form of the method uses two images of a point source, one with a small modification introduced in the pupil. The algorithm to recover the pupil field uses a functional derivative of the optical transfer function (OTF), and is simple and non-iterative. The derivative is approximated empirically by the difference between the Fourier transforms of the two PSFs: the differential OTF or dOTF. In keeping with the Hermitian symmetry of the OTF, the dOTF includes two conjugate copies of the pupil field overlapping at the point of modification. By placing the modification near the edge of the pupil, the overlap region can be kept small. It can be eliminated altogether by using a second modification and a third image. The technique can be used in broadband light, at the cost of blurring in the recovered phase that is proportional to the fractional bandwidth. Although the dOTF is unlikely to find application in high frame rate astronomical adaptive optics, it has many potential uses such as optical shop testing, non-common-path wavefront error estimation, segmented telescope phasing and general imaging system diagnostics. In this paper, we review the dOTF concept, theory, and initial experiments to demonstrate the technique.
Gab1 signaling is regulated by EGF receptor sorting in early endosomes

Although combinatorial signaling through the ErbB network is implicated in certain types of human cancer, the specifics of how particular receptors contribute to the transformed phenotype are not well understood. The goal of this study was to identify epidermal growth factor (EGF) receptor-dependent cell signaling abnormalities specifically associated with mutations in a previously described 679-LL lysosomal sorting signal, which restrict ligand-dependent receptor downregulation by promoting recycling. Importantly, the 679-LL signal is not conserved in any of the other members of the ErbB receptor family suggesting its physiological function may be tightly regulated during EGF receptor-dependent signaling. Our data indicate that cells expressing receptors with an inactive 679-AA signal are rapidly transported to Rab4+ early endosomes after they are internalized in contrast to wild-type receptors that are localized to early endocytic antigen 1 (EEA1)+ early endosomes. Divergent trafficking in early endosomes is associated with prolonged activation of p44/42 mitogen-activated protein kinases (MAPK) but not Akt. Gab1 appears to be the critical signaling molecule facilitating prolonged MAPK signaling, and activated Gab1 is recruited to early endosomes in 679-AA receptor-expressing cells. Activated Gab1 is also recruited to early endosomes in breast cancer cells characterized by high levels of EGF receptor-ErbB2 heterodimers, suggesting 679-AA expressing cells recapitulate certain aspects of EGF receptor signaling and transformation by activated ErbB2. Phosphatidylinositol 3-kinase (PI3K)-dependent membrane translocation known to be important for maintaining Gab1 activity in other settings was dispensable. We conclude that 679-LL has dual functions in EGF receptor trafficking and threshold signaling through a subset of signaling molecules including p44/42 MAPK and Gab1.
The role of behaviour in the establishment of novel traits

It may seem as if behaviour is so plastic that it would not foster the establishment of a genetically determined trait, but under some circumstances, it can greatly influence whether a novel trait, such as a new morphology, spreads in a population. If the behaviours associated with the trait's function already exist, a new variant finds a ready foothold, and selection can act accordingly. Behaviours that are particularly likely to foster novel traits include those that play a role in life history, such as antipredator behaviour, sexual signalling and foraging. Examples of behaviour facilitating novel trait establishment include the spread of a silent mutant in male Pacific field crickets, Teleogryllus oceanicus, and the propensity of juvenile fence lizards to show antipredator behaviours towards attacking fire ants, providing a selective opportunity for the evolution of longer limbs. The genetic or physiological mechanisms behind a behaviour can also influence its establishment; for example, learning may generate selection in favour of conspicuous novel traits faster, and for a wider range of traits, than genetically based sensory biases. Just as changes in behavioural traits over evolutionary time may expose populations of individuals to new adaptive zones, behavioural variation within a population may increase the diversity of environments to which individuals are exposed.
On the Parsing of Deterministic Languages

A parsing method for strict deterministic grammars is presented and a technique for using it to parse any deterministic language is indicated. An important characterization of the trees of strict deterministic grammars is established. This is used to prove iteration theorems for (strict) deterministic languages, and hence proving that certain sets are not in these families becomes comparatively straightforward. It is shown that every strict deterministic grammar is LR(0) and that any strict deterministic grammar is equivalent to a bounded right context (1, 0) grammar. Thus rigorous proofs that the families of deterministic, LR (k), and bounded right context languages are coextensive are presented for the first time.
On the Maximum Directional Target Coverage Problem in Wireless Sensor Networks

Due to technological advances in micro-electronics, digital electronics, and wireless data communications, we have witnessed the advent of Wireless Sensor Networks (WSNs) and related applications in many areas such as battlefield surveillance, environmental monitoring, and biomedical observation. In this paper, we investigate the Maximum Directional Target Coverage Problem (MDTCP) for a special group of wireless sensor networks in which each sensor has a specific coverage range and a limited coverage angle. Given a set of sensors and a set of target points in a finite area, the objective of MDTCP is to cover the maximum number of target points by adjusting the directions of sensors. We develop a polynomial time approximation algorithm with performance ratio 1 -- e/e for MDTCP. In addition, we also analyze the structure of MDTCP from the Combinatorics' point of view.
Metabolic Adaptation of the Hypertrophied Heart: Role of the Malate/Aspartate and α -Glycerophosphate Shuttles ☆

Activation of the malate/aspartate and α -glycerophosphate shuttles (the NADH shuttles) has been identified in glycolytically active newborn myocardium. The goal of this study was to determine if the NADH shuttles and their regulatory genes are activated in hypertrophied myocardium as substrate utilization shifts away from fatty acids and toward glucose and lactate. Capacity of the shuttles was determined in cardiac mitochondria isolated one week, one month, and three months following aortic banding or sham operation. Myocardial steady-state mRNA and protein levels of regulatory enzymes were also measured. Despite a significant increase in left ventricular mass and activation of the atrial natriuretic peptide gene, no change in malate/aspartate nor α -glycerophosphate shuttle capacity was found at any of the three time points studied. Reactivation of the genes encoding the regulatory inner mitochondrial membrane proteins was not found in the hypertrophied myocardium, though these genes were down regulated one week following aortic-banding. These results suggest that sufficient malate/aspartate and α -glycerophosphate shuttle capacity exists in cardiac mitochondria to accommodate increased shuttle flux as hypertrophied myocardium becomes more glycolytically active.
Psychiatric disorder in children with different types of communication disorders

Children presenting to a community speech clinic were divided into three major groups according to type of communication disorder: a pure speech disorder, a pure language disorder, and a disorder of both speech and language. Psychiatric evaluations of the three groups of children were done employing interviews with the parents, interviews with the children, and questionnaires from the children's teachers and parents. It was found that the prevalence of psychiatric disorder was highest in the language-disordered group and lowest in the speech-disordered group. Development disorders were also most common in the language-disordered group and least common in the speech-disordered group. The types of psychiatric disorders found in the three groups of children also differed. The implications of these findings are discussed.
Tax Incidence in a Growing Economy with Variable Factor Supply

I. A one-sector general equilibrium analysis, 553. — II. A numerical example, 560. — III. Long-run incidence in a growing economy, 563. — IV. The path of adjustment, 570. — V. Conclusion, 572.
Anti-inflammatory action of alpha-1-acid-glycoprotein in urate crystal inflammation.

Injections of alpha-1-acid-glycoprotein along with urate crystals induced less footpad swelling than that caused by injections of urate crystals alone. This anti-imflammatory action of acid-glycoprotein is considered to add further support to the hypothesis that perturbations in acute phase proteins are protective.
603 UREA NITROGEN EXCRETION OF CRITICALLY ILL CHILDREN

Urinary urea nitrogen (UUN) excretion as an index of protein catabolism was assayed in 32 children (2m to 15y, median 6y)(50% mechanically ventilated) during an ICU course of 1 to 10 days (median 3d). Mean daily UUN excretion was 171 ± 89 mg/kg (4.38 ± 2.22 gm/m2), with greater excretion within 24 hours of ICU admission than subsequently. Average daily nitrogen balance per child was - 146 ± 82 mg/kg (-3.73 ± 2.04 gm/m2), and was independent of caloric intake.
EVIDENCE FOR A PHYSIOLOGICAL EXPLANATION OF THE WATERFALL PHENOMENON AND FIGURAL AFTER-EFFECTS.

IN the rabbit's retina ganglion cells have recently been found which signal the direction of motion of objects moving in the visual field1,2. These cells give brief responses at ‘on’ and ‘off’ to lights falling in their receptive fields and they give vigorous responses to moving spots, but only when these are moved in certain directions through their fields. Motion in the ‘preferred’ direction gives the maximum discharge, while motion in the opposite, ‘null’, direction, causes no response. The ‘preferred’ direction differs in different units: thus which of a set of cells are active conveys information as to the direction of motion of objects in the visual field. The frequency of the discharge depends greatly on speed and direction of motion, but is only slightly influenced by the intensity of the moving stimulus spot. Furthermore, the discharge occurs for the same direction of motion with a black spot as with a white spot. This behaviour is what one might expect in units of which the function is to abstract direction of motion from the pattern of light falling on the retina.
Flame fusion growth of chromic oxide crystals

Abstract Powder preparation procedures and growth conditions are reported for the synthesis of large Cr 2 O 3 crystals of good physical quality by the flame fusion process. Typical 65-gram crack-free crystals, with dislocation densities of the order of 10 5 /cm 2 and dimensions of 1.5 cm in diameter by 7 cm in length can readily be grown at a rate of 0.5 mm/min.
MR imaging during endovascular procedures: an evaluation of the potential for catheter heating.

MRI in catheterized patients is considered unsafe due to the potential for focal heating. This concern arises from the continuous metallic braid that is incorporated into catheters to provide their desired physical properties. The potential for catheter heating during MR scanning was assessed in an in vitro model simulating a patient undergoing a neurovascular procedure in which MR scans of the brain will be performed. Heating adjacent to endovascular devices was assessed with fluoroptic temperature probes in a polyacrylamide gel. The effect of variable immersion lengths, lateral and longitudinal offsets, position along the endovascular device, physical MR system, and specific absorption rate (SAR) level were studied to determine their effect on catheter heating. A rapid temperature rise was evident next to endovascular devices during MR scanning and varied moderately with immersed length, position within the bore, measurement point on the device, and MR system used. Peak heating rates were less than 1°C/min with maximal SAR exposure and anatomically realistic geometries. Heating scaled linearly with SAR and SAR values below 0.2 W/kg produced negligible heating near catheters. For the evaluated application, substantial SAR restrictions, coupled with limited imaging durations, are proposed as sufficient to permit MRI without concern for thermal injury. Magn Reson Med 61:45–53, 2009. © 2008 Wiley-Liss, Inc.
Winning the Silicon Sweepstakes: Can the United States Compete in Global Communications?

Frieden, R. (2010). Winning the Silicon Sweepstakes: Can the United States Compete in Global Communications? New Haven, CT: Yale University Press. 409 pages. Do you feel lucky to live in an age whe...
Multifidi muscles median frequency before and after spinal stabilization exercises.

Abstract Sung PS. Multifidi muscles median frequency before and after spinal stabilization exercises. Arch Phys Med Rehabil 2003;84:1313–8. Objective To determine changes in multifidi muscle endurance and functional status after a 4-week spinal stabilization exercise program for patients presenting with chronic low back dysfunction (LBD). Design Short-term longitudinal cohort study. Setting A rehabilitation facility. Participants Sixteen patients (10 men, 6 women) with chronic LBD. Interventions Patients were evaluated pre- and posttreatment for outcomes of functional status and muscle fatigue. Treatment consisted of patients participating in supervised spinal stabilization exercises 3 times a week over a 4-week period. Main outcome measures Oswestry Low Back Pain Disability Questionnaire and muscle fatigue based on electromyographically based median frequency assessed during the first 4 seconds and the last 4 seconds of a modified 1-minute Sorenson test. Results Oswestry scores improved significantly from pre- to posttreatment (22.9 vs 18.3, P P P P Conclusions A 4-week spinal stabilization exercise program significantly improved functional status in patients presenting with LBD. However, a significant pre- to posttreatment increase in multifidi muscle fatigue for men ( P P
Measurement of generation lifetime in thin silicon layers

Abstract This paper describes an improved capacitance method for the measurement of the minority carrier generation lifetime in the near surface region in thin silicon layers. The technique provides a simple experimental means for evaluating interferences in the leakage current, such as diffusion from the quasi-neutral bulk and peripheral generation, permitting a more accurate determination of the lifetime. Additional, related capacitance measurements are performed on adjacent circular capacitors of differing radii to quantify the extent of peripheral generation. Results are presented demonstrating application of the method and illustrating the magnitude of these interferences. These results indicate that the accurate determination of the generation lifetime in current, high quality silicon necessitates the use of experimental means, such as the technique described here, in order to quantify interference components in the leakage current. Assumptions underlying the technique and limitations in its use are discussed.
The Structure of Genetic Linkage Data: From LIPED to 1M SNPs

There are three assumptions of independence or conditional independence that underlie linkage likelihood computations on sets of related individuals. The first is the independence of meioses, which gives rise to the conditional independence of haplotypes carried by offspring, given those of their parents. The second derives from the assumption of absence of genetic interference, which gives rise to the conditional independence of inheritance vectors, given the inheritance vector at an intermediate location. The third is the assumption of independence of allelic types, at the population level, both among haplotypes of unrelated individuals and also over the loci along a given haplotype. These three assumptions have been integral to likelihood computations since the first lod scores were computed, and remain key components in analysis of modern genetic data. In this paper we trace the role of these assumptions through the history of linkage likelihood computation, through to a new framework of genetic linkage analysis in the era of dense genomic marker data.
Long-term evaluation of the hepatitis B vaccine (Heptavax-B) in hemodialysis patients.

Hemodialysis patients were screened for hepatitis B surface antibody (anti-HBs) prior to immunization at two teaching hospitals. Thirty-one of 111 patients (28/0) had baseline sera positive for anti-HBs, while anti-HBs was found in 30 of 420 (7.1%) health care employees ( P P > 0.05) nor injection site ( P > 0.05) appeared to influence results. Nonresponders (16 of 17; 94%) who were given a fourth vaccine dose also failed to mount an antibody response. Of the 34 responders, 18 were followed by serial anti-HBs determinations. Seven transient responders (7 of 18; 39%) were identified, and anti-HBs fell below 10 S/N (sample/control counts per minute) within 12 to 15 months of the first vaccine dose. A fourth dose was administered to this group and it extended the presence of serum anti-HBs (S/N ≥ 10) in four of six patients for another 2, 8, 10, and 15 months, respectively. Antibody persisted but declined over the study period in the remainder of responders followed serially (11 of 18; 61 %). When compared with those responders who lost anti-HBs, those with persistent antibody had higher anti-HBs values at 7 ( P P P
The Validity of Student Assessments of Principals' Competencies.

AbstractUsing 35 elementary schools (3,350 fourth and sixth grade students), 10 secondary schools (3,613 eight and eleventh grade students), and 1,145 teachers, this study presents data summarizing the relationships between student' perceptions of "verified" principal competencies and selected school climate indices and outcome variables. The results indicated that there is a general tendency for positive teacher attitudes towards various dimensions of the school and working environment and higher student standardized achievement test performance to be associated with students' reports of a low frequency of interaction with die principal. A student "independence factor" was hypothesized to account for these results, with the implication being that principal/student interaction is minimized in schools where teacher and student attitudes are positive and student achievement is high. In addition, effective principal performance in dealing with student misbehavior was highly and positively associated with sch...
Large Surface Carbon Dioxide Anomalies in the North Pacific Ocean

DURING the trans-Pacific Lusiad expedition of R.V. Argo, May 18–June 9, 1962, Waterman observed a large inequality of the partial pressure of the carbon dioxide in the atmosphere and in the surface water in the centre of the North Pacific Ocean1. His traverse (Fig. 1) showed that the partial pressure of carbon dioxide (PCO2) in the water was generally less than that in the atmosphere (320 p.p.m.), with a maximum anomaly of about 20 per cent. This difference in PCO2 is too large to be accounted for solely by changes in temperature, salinity, or solution of calcium carbonate2. Our recent work shows that the carbon dioxide anomaly is of biological origin. It is similar to, but of greater dimensions than, the biologically induced carbon dioxide anomalies found by Teal and Kanwisher3.
Outcomes of root canal treatment and restoration, implant-supported single crowns, fixed partial dentures, and extraction without replacement: A systematic review

Statement of problem Dentists and patients are regularly confronted by a difficult treatment question: should a tooth be saved through root canal treatment and restoration (RCT), be extracted without any tooth replacement, be replaced with a fixed partial denture (FPD) or an implant-supported single crown (ISC)? Purpose The purpose of this systematic review was to compare the outcomes, benefits, and harms of endodontic care and restoration compared to extraction and placement of ISCs, FPDs, or extraction without tooth replacement. Material and methods Searches performed in MEDLINE, Cochrane, and EMBASE databases were enriched by hand searches, citation mining, and expert recommendation. Evidence tables were developed following quality and inclusion criteria assessment. Pooled and weighted mean success and survival rates, with associated confidence intervals, were calculated for single implant crowns, fixed partial dentures, and initial nonsurgical root canal treatments. Data related to extraction without tooth replacement and psychosocial outcomes were evaluated by a narrative review due to literature limitations. Results The 143 selected studies varied considerably in design, success definition, assessment methods, operator type, and sample size. Direct comparison of treatment types was extremely rare. Limited psychosocial data revealed the traumatic effect of loss of visible teeth. Economic data were largely absent. Success rates for ISCs were higher than for RCTs and FPDs, respectively; however, success criteria differed greatly among treatment types, rendering direct comparison of success rates futile. Long-term survival rates for ISCs and RCTs were similar and superior to those for FPDs. Conclusions Lack of comparative studies with similar outcomes criteria with comparable time intervals limited comparison of these treatments. ISC and RCT treatments resulted in superior long-term survival, compared to FPDs. Limited data suggested that extraction without replacement resulted in inferior psychosocial outcomes compared to alternatives. Long-term, prospective clinical trials with large sample sizes and clearly defined outcomes criteria are needed.
A high dimensional immune monitoring model of HIV-specific CD8 T cell responses accurately identifies subjects achieving spontaneous control of viral replication

A major challenge in HIV vaccinology is the development of appropriate immune monitoring models to determine vaccine efficacy. Studies of HIV-specific CD8 T cells (CTL) suggest that these responses play an important role in infected individuals capable of spontaneous viral control (HIV elite controllers) and that they will likely play a role in immune interventions. However, no single CTL assay is uniquely associated with the controller phenotype.
Uniform boundary stabilization of von Karman plates

The author considers the determination of feedback controls which act along the edge of a thin plate and whose purpose is to stabilize the motion of the plate uniformly in situations where the deviation of the plate from equilibrium is not necessarily small, and therefore, is not adequately modeled by linear plate theory. The analysis deals mainly with the classical von Karman plate model. It is shown that the physical assumptions usually associated with the von Karman model lead to a coupled system of three nonlinear second-order partial differential equations for the three components of the displacement vector. The von Karman model is then obtained by imposing an additional hypothesis which does not seem to be altogether reasonable from a physical standpoint. The uniform asymptotic stability of the von Karman model is then studied. >
Mechanical stability of microkeratome-assisted intracorneal keratoprosthesis implantation.

Objective To develop a laboratory model to study intracorneal keratoprosthesisimplantation. Methods A combination microkeratome and artificial anterior chamber system wasused to create a hinged lamellar keratectomy on 13 human corneas. After reflectingthe flap, the posterior stroma was trephined at either 2.5 or 3.0 mm. A modelkeratoprosthesis was positioned in the bed. The flap was sutured closed. Intrachamberpressure was increased, and wound leak pressure was recorded. The anteriorcorneal lamella was trephined at either 3.0 or 3.5 mm to expose the keratoprosthesis.Leak pressure was again determined. Results After keratoprosthesis placement and prior to anterior trephination,all 13 corneas were watertight at maximum attainable intrachamber pressures.With posterior/anterior trephination combinations of 2.5/3.0 mm, 2.5/3.5 mm,or 3.0/3.5 mm, mean ± SD wound leak pressure occurred at95 ± 12 mm Hg, 32 ± 7 mm Hg, or 59 ± 12mm Hg, respectively ( P Conclusions With a posterior trephination of 2.5 mm, there is significant keratoprosthesis-corneainterface destabilization between a 3.0- and 3.5-mm anterior trephination.For an anterior trephination of 3.5 mm, interface destabilization improvesby increasing the posterior trephination to 3.0 mm. Clinical Relevance An intracorneal keratoprosthesis may be implanted using microkeratomeassistance. Our laboratory model provides a useful method for examining arange of posterior and anterior trephination diameters and their effects onthe mechanical stability of intracorneal keratoprosthesis placement.
CRH peptides modulate human hair follicle growth in vitro– a preliminary study

Mammalian skin may contain an equivalent of the hypothalamic-pituitary-adrenal axis (HPA), composed of locally produced corticotropin-releasing hormone (CRH) that, together with signalling via CRH receptor 1 (CRH-R1) and CRH-R2, may regulate local homeostasis. Studies in murine skin have demonstrated significant hair cycle-dependent fluctuations in the expression of CRH and urocortin peptides and CRH-Rs genes, suggesting a modulatory role for this signalling system in hair growth/cycling. This study was designed to investigate the effects of ligands showing increased selectivity for CRH-R1 [(D-Glu20)-CRH (10−7 and 10−8 m)] and CRH-R2 [(D-Pro5)-CRH (10−8 and 10−9 m)] and (D-Pro4)-urocortin (10−7 and 10−8 m) on human hair growth in ex vivo culture. (D-Pro5)-CRH can also activate CRH-R1, while (D-Pro4)-urocortin is highly selective for CRH-R2. Anagen hair follicles (HFs) were isolated from human scalp and stimulated for 9 days, with 10 HFs tested per CRH peptide concentration. Preliminary findings indicate that (D-Pro4)-urocortin (10−8 m) stimulated a 79% mean hair fibre elongation compared to the initial HF length over the 9-day study period. (D-Glu20)-CRH (10−8 m) also stimulated hair fibre elongation of 63% of initial length, while (D-Pro5)-CRH (10−9 m), which inhibited hair fibre elongation, compared to unstimulated controls. In agreement with our previous detection of CRH-R1 and CRH-R2 in human HFs, the above data suggest the existence of a functionally active CRH peptide/receptor system in cultured human HFs and suggest that signalling via these receptors may participate in the regulation of human hair growth/cycling in vivo.
Autoxidation of Beef and Tuna Oxymyoglobinsa

SUMMARY Rates of autoxidation of beef and tuna oxymyoglobins have been determined at pH 5.9 with various buffer concentrations (0.1, 0.2, and 0.6M) and temperatures ranging from 0 to 40°C. The autoxidation is first-order with respect to unoxidized myoglobin under all conditions used. The rates of oxidation of tuna oxymyoglobin were independent of buffer concentration, whereas those of beef myoglobin decreased with increasing buffer concentration. Tuna oxymyoglobin was oxidized more slowly than beef at 0 to 10°C at all buffer concentrations, and at higher temperatures and low buffer concentration; at high temperatures and high buffer concentration, tuna oxymyoglobin was oxidized more rapidly than beef. Oxidation of a crude preparation of beef oxymyoglobin was slower than that of purified myoglobin.