cssi/SciSciGPT-SciSciNet huggingface dataset:
Three‐dimensional magnetosphere movies

Early next century, watching the “weather” in Earth's magnetosphere could be as commonplace as watching satellite imagery of cloud fronts marching across the landscape on the evening news. Scientists at the Los Alamos National Laboratory, New Mexico, are leading a national team that is developing a pair of instruments to provide three-dimensional imagery of changing conditions in the magnetosphere.
Uniform processing of V-shaped and tri-planar composite parts using microwaves

Uniform processing of V-shaped and tri-planar graphite/epoxy composite parts has been achieved in a single mode cavity using variable frequency microwave energy. A computer process control system was used to achieve uniform heating and stable curing temperature. The control parameters were microwave frequency and power. The control algorithm was mainly composed of two parts: intelligent mode selection for uniform heating, and power control for constant curing temperature. Experimental results were compared between single mode heating, mode sweeping heating, and intelligent mode switching heating. The comparison showed significant improvement of temperature uniformity using the intelligent mode switching technique.
PLEED studies of the temperature dependence of the surface vs bulk magnetization of Ni(110)

Abstract The temperature dependence of the bulk and surface magnetization of Ni(110) is derived using the molecular field theory. These results are then used in a dynamical polarized low-energy-electron-diffraction (PLEED) calculation to yield the temperature dependent polarization of the diffracted intensities, which is compared with recent experimental data for 0.6 TCurie ≤ T ≤ TCurie. The importance of multiple scatterings and the usefulness of PLEED for surface magnetic structural determination are clearly demonstrated.
Effect on Coagulation Time of Oral Administration of Rabbit Thrombin

Parfentjev1 recently described a method for the preparation of pseudoglobulin of rabbit plasma having a high clot-promoting activity. Parfentjev's preparation has been repeated and the activity associated with this pseudoglobulin was found to be thrombic in nature.2 This was indicated by the ability of the pseudoglobulin fraction to coagulate pure fibrinogen solution in the absence of calcium and to coagulate citrated and oxalated plasma from which pro-thrombin had been removed. Evidence indicating that this material may have clinical applications as a powerful hemostatic when applied locally to small wounds has also been presented.3The present communication reports the effect of the oral administration of relatively large amounts of pseudoglobulin from rabbit plasma, hereafter referred to as “rabbit thrombin”, to dogs, normal subjects and patients suffering from hemophilia.Methods. Coagulation times were determined on venous blood by the standard procedure formerly described.4 In certain instances the bl...
A discrete Perron–Ta Li type theorem for the dichotomy of evolution operators☆

Following the Perron–Ta Li line of results, we give a characterization of the uniform exponential dichotomy property for the abstract continuous-time evolution families using a discrete-time approach.
Recovery from chlorphentermine-induced phospholipidosis in rat alveolar macrophages: Morphological features

Abstract Rats were treated for 4 weeks with the amphiphilic, anorexic drug chlorphentermine resulting in the induction of a phospholipid storage disorder in alveolar macrophages. When examined with the electron microscope, the cells were found to be filled with lamellarshaped and membranous inclusions often associated with amorphous granular and membranous material. These features presumably represent the accumulated phospholipid which occurs with this disorder. We have previously reported that following withdrawal of the rats from chlorphentermine treatment, the phospholipid content of the macrophages returned to the control level by 14 days of recovery (Reasor and Koshut, Toxicol. Appl. Pharmacol.55, 334–341, 1980). Morphological features of the cells were examined at various times after termination of drug treatment in order to monitor the recovery process from this perspective. After 7 days of recovery, the macrophages were generally free of the amorphous material, however, they contained prominent lamellar inclusions. At 14 days of recovery, most of the cells contained large pleomorphic bodies, which were probably autophagic vacuoles. These structures appeared to be involved in degrading the lamellar material and converting it into residual bodies. At 21 days of recovery, most of the macrophages appeared normal, although some contained structures similar to those present at 14 days of recovery. By 28 days of recovery, essentially all of the macrophages were normal in appearance. Therefore, while the phospholipid content of the cells returned to the control level by 14 days of recovery, the cells still had an altered morphological appearance. Thus, assessment of recovery from phospholipidosis should not be based on phospholipid content alone.
Managing the suicidal patient.

Abstract Suicide is a major public health problem. Worldwide, approximately I % of deaths are due to suicide. In the United States, suicide is the eighth leading cause of death. More than 30,000 Americans commit suicide each year, and nearly 500,000 others make a serious suicide attempt warranting emergency medical attention. Suicide attempts account for 23% of psychiatric visits to emergency rooms.
Peripheral arterial disease and cognitive function.

OBJECTIVE Peripheral arterial disease (PAD) is associated with comorbid atherosclerosis of the coronary and carotid arteries and is a significant risk factor for stroke. However, cognitive function in PAD patients before clinically evident stroke remains poorly characterized. Here we hypothesized that, on neuropsychological testing, PAD patients would perform more poorly than healthy control subjects, and persons with mild cardiovascular disease (essential hypertension), but better than stroke patients, thus reflecting a continuum of cognitive impairment associated with increased severity of vascular disease. METHOD The cognitive performance of 38 PAD patients (mean ankle-brachial index=0.67, Fontaine Class II) was contrasted with that of 23 healthy normotensive controls, 20 essential hypertensives, and 26 anterior ischemic stroke patients on twelve neuropsychological tests. RESULTS PAD patients performed significantly more poorly than hypertensives and normotensives, but better than stroke patients, on seven tests of nonverbal memory, concentration, executive function, perceptuo-motor speed, and manual dexterity. Hypertensives displayed poorer performance than normotensives on tests of nonverbal memory and manual dexterity. These findings were independent of age, education, and depression scores. Higher diastolic blood pressure and plasma glucose levels predicted poorer performance of select cognitive tests by PAD patients. Eight to 67% of PAD patients displayed impaired performance (< 5(th) percentile of normotensive controls) on the seven aforementioned cognitive tests. CONCLUSIONS PAD patients exhibit diminished performance across a variety of domains of cognitive function. Findings also suggest a continuum of cognitive impairment associated with increasingly severe manifestations of cardiovascular disease, thus emphasizing the need for enhanced preventative measures to avert functional declines.
Trajectory analysis of low-energy and hyperthermal ions scattered from Cu(110).

We have investigated the trajectories of Na/sup +/ ions scattered from the Cu(110) surface in the and azimuths for a range of incident energies from 56 eV to 4 keV. Our goal is to explain the trends observed in the energy spectra and determine what types of trajectories contribute to these spectra. Using the computer program SAFARI, we have performed simulations with trajectory analyses for 100-, 200-, and 400-eV scattering. We show results from the 100-eV simulations in both azimuths and compare them with the experimental data. The simulated energy spectra are in excellent agreement with the data. Ion trajectories and impact parameter plots from the simulations are used to determine the relative importance of different types of ion--surface-atom collisions. The simulations have shown that the striking differences observed in comparing the and spectra are mostly due to ions which scatter from second-layer atoms. This system exhibits strong focusing onto the second-layer atoms by the first-layer rows, and the focusing is very sensitive to the spacing between the rows. At the lower beam energies, scattering from the second layer dominates the measured spectra.
Statistical mechanics of oscillating neutrinos

Abstract A Langevin equation is used to study the time evolution of the density matrix of a two-state system in which one of the states interacts with a thermal bath, but the other has no interactions. The interaction eigenstates are not energy eigenstates, so that the interaction eigenstates oscillate with time. The rate of approach to equilibrium of the non-interacting state is suppressed relative to that of the interacting state. The results are important for the analysis of singlet neutrinos in the early universe.
An approach to heart failure and diabetes mellitus.

Diabetes mellitus is a chronic progressive disease that results in microvascular and macrovascular complications. Diabetes is a significant independent risk factor for heart failure, and there are a substantial number of patients with diabetes and heart failure. Neurohormonal activation plays an important pathophysiologic role in insulin resistance, diabetes, cardiovascular events, and progression of heart failure. Pharmacologic intervention in these neurohormonal systems (ie, angiotensin-converting enzyme [ACE] inhibition, aldosterone antagonism, and β-adrenergic blockade) has been shown to decrease the morbidity and mortality of diabetes and of heart failure. Despite this knowledge, ACE inhibitors, aldosterone antagonists, and β-blockers are grossly underutilized, and deaths and hospitalizations due to heart failure have steadily increased. Guidelines for the management of heart failure recommend the use of ACE inhibitors and β-blockers in patients with mild, moderate, and severe heart failure with or without diabetes. Aldosterone antagonists are recommended in severe heart failure and recent data also support their use in mild to moderate heart failure. Concerns about increased incidence of hypoglycemia, worsening dyslipidemia, and decreased insulin sensitivity with β-blockers may be preventing physicians from prescribing these agents for their patients with diabetes who have heart failure. β-Blockade, in conjunction with ACE inhibition and aldosterone antagonism, should be standard therapy for all patients with diabetes and heart failure. Furthermore, every effort should be made to ensure that eligible patients are treated with these evidence-based, guideline-recommended, life-prolonging therapies.
In Vitro Activity of Furazlocillin (Bay k 4999) Compared with Those of Mezlocillin, Piperacillin, and Standard Beta-Lactam Antibiotics

The activity of furazlocillin (Bay k 4999) was compared with those of mezlocillin, piperacillin, and standard beta-lactam antibiotics against a number of gram-positive and gram-negative organisms. These new expanded-spectrum penicillins were less active than penicillin G against most gram-positive organisms. Furazlocillin, mezlocillin, and piperacillin showed activity comparable to ampicillin and penicillin G against Haemophilus influenzae and penicillin-susceptible neisseriae, respectively. None of the drugs tested was effective against penicillin-resistant gonococci. The activity of furazlocillin was greater than that of mezlocillin, piperacillin, ampicillin, or carbenicillin against many Enterobacteriaceae. However, certain beta-lactam-resistant strains among these organisms were not highly susceptible to any of the three new penicillins. Furazlocillin was less active than piperacillin against Pseudomonas aeruginosa but was more active than carbenicillin or mezlocillin. Inoculum effects and discrepancies between minimal inhibitory concentrations and minimal bactericidal concentrations were observed with furazlocillin, mezlocillin, and piperacillin against several genera. The kinetics of bacterial killing by the new penicillins were often slow and incomplete over 24 h, especially in tests with Enterobacter and P. aeruginosa. Synergy was demonstrated between furazlocillin and aminoglycosides against a variety of gram-negative bacilli and Streptococcus faecalis.
Microneutralization Test for the Reoviruses. Application to Detection And Assay of Antibodies in Sera of Laboratory Animals.

SummaryThe problem of determining the specificity of hemagglutination-inhibiting activity for reovirus type 3 seen in mouse, hamster and rat sera examined as part of a mu-rine virus monitoring program, together with the need for a sensitive and efficient technic for detection of reovirus antibodies in the sera of other laboratory animals, led to the development of a microneutralization technic. The test, conducted in a HeLa cell system in disposable microplates, is a modified metabolic inhibition procedure which permits reading of results colorimetrically. The results obtained in microneutralization tests showed good correlation with those obtained in conventional neutralization tests conducted in tube cultures of monkey kidney cells. The technic was found to be suitable for detection of antibodies to all 3 reovirus types in sera of a variety of species, and it is particularly useful for monitoring rodent colonies for reovirus type 3 infections. HI tests appeared to possess less specificity than neutraliz...
Diagnosing Bootstrap Success

We show that convergence of intuitive bootstrap distributions to the correct limit distribution is equivalent to a local asymptotic equivariance property of estimators and to an asymptotic independence property in the bootstrap world. The first equivalence implies that bootstrap convergence fails at superefficiency points in the parameter space. However, superefficiency is only a sufficient condition for bootstrap failure. The second equivalence suggests graphical diagnostics for detecting whether or not the intuitive bootstrap is trustworthy in a given data analysis. Both criteria for bootstrap convergence are related to Hajek's (1970, Zeit. Wahrscheinlichkeitsth., 14, 323-330) formulation of the convolution theorem and to Basu's (1955, Sankhyā, 15, 377-380) theorem on the independence of an ancillary statistic and a complete sufficient statistic.
Students' Mathematical Modeling of Motion

Abstract: We present results of an investigation of university students’ development of mathematicalmodels of motion in a physical science course for preservice teachers and graduate students in science andmathematics education. Although some students were familiar with the standard concepts of position,velocity, and acceleration from physics classes, most students had difﬁculty using these concepts tocharacterize actual or hypothetical motions. Furthermore, some students developed their own nonstandardmethod of describing accelerated motion in terms of changes in the average velocity, from the start of themotion up to a given time. This is in contrast to the physics community’s use of the acceleration construct,deﬁned in terms of changes in the instantaneous velocity, to describe such motion. Although the change inaverage velocity is not typically identiﬁed as an important construct in traditional physics texts, somestudents found it intuitively appealing, and were able to use it successfully to describe and predict motion.We conclude that by focusing on standard constructs, and ignoring possible intuitive ways that studentsmight view motion, standard kinematics instruction may miss an opportunity to maximize studentunderstanding. 2007 Wiley Periodicals, Inc. J Res Sci Teach 45: 153–173, 2008Keywords: physical science; inquiry; college/university; classroom research
Exploring the nature of transformational leadership in sports: a phenomenological examination with female athletes

Transformational leaders lift and inspire followers to achieve performance beyond expectations and realise their full potential. Transformational leadership fosters performance and increases positive outcomes in a variety of domains (e.g. business, military, and education) and may have a salient impact on the quality of athletes’ sporting experiences. Bass identified four primary behavioural components of transformational leadership: idealised influence, inspirational motivation, intellectual stimulation, and individualised consideration. Yet little is known about what constitutes transformational leadership in a sport setting from a qualitative perspective. This study addressed this issue by interviewing eleven female collegiate athletes about their positive experiences with current or former coaches. Thematic analysis of transcribed interview text revealed four major themes: caring, motivating, teaching life lessons, and trusting. Caring was exemplified by the coach taking the time and energy to establi...
Primary cytodiagnosis of peritoneal extramedullary hematopoiesis.

Cytologic examination of peritoneal fluid in a patient with known myelofibrosis and previous splenectomy revealed mega-karyocytes along with erythroid and myeloid precursors. These findings were consistent with extramedullary hematopoietic (EMH) implants of the peritoneum. A few similar cases have been occasionally reported in the literature. This case represents an additional example of a primary diagnosis of peritoneal EMH in which therapy was based on the cytologic findings and sequential cytologic observations were made. Diagn Cytopathol 1986;2:241 243.
Object pose determination from range data

Abstract This paper is concerned with determining the position and orientation of a three-dimensional object from range data. An algorithm is presented which uses an enclosing object and the central moments for an initial estimate of pose. A refined estimation is obtained by a nonlinear least squares technique. The use of an enclosing object reduces the number of parameters which must be solved for by the nonlinear least squaes estimation. An object representation based on a relational graph of superquadric primitives is used for description so that the method is applicable for 3-D objects of general shapes.
Colloidal Assemblies of Branched Geminis Studied by Cryo-etch-HRSEM

Cryo-etch-HRSEM is introduced as a useful method for exploring colloidal systems. The method fast freezes an aqueous sample (to −105 °C in 6−7 ms), removes some or all of the surface water by sublimation (etching), and magnifies the resulting colloidal structure by up to a million. Three new structurally similar gemini surfactants served to illustrate the technique. One gemini formed a gel whose delicate fractal-like molecular web could be observed after 10-min etching. A second formed a coacervate with a more hydrated porous structure. The third displayed a “bumpy” surface consistent with spherical vesicles projecting from the vitreous ice. The information-content of cryo-etch-HRSEM is pictorial but distinctive in nature.
Bradykinin pretreatment improves ischemia tolerance of the rabbit heart by tyrosine kinase mediated pathways.

Abstract Background . Depressed myocardial performance is an important clinical problem after open-heart surgery. We hypothesized that: (1) pretreating the heart with bradykinin improves postischemic performance, and (2) bradykinin activates protein tyrosine kinase (TK). Methods . Twenty-seven adult rabbit hearts underwent retrograde perfusion with Krebs-Henseleit buffer (KHB) followed by 50 min of 37°C cardioplegic ischemia with St. Thomas' cardioplegia solution (StTCP). Ten control hearts received no pretreatment. Ten bradykinin-pretreated hearts received a 10-minute infusion of 0.1 μM bradykinin-enriched KHB and cardioplegic arrest with 0.1 μM bradykinin-enriched StTCP. Seven others received 40 μM Genistein (Research Biochemicals, Natick, MA), a selective inhibitor of TK, added to both the 0.1-μM bradykinin-enriched KHB and 0.1-μM bradykinin-enriched StTCP solutions. Results . Bradykinin pretreatment significantly improved postischemic myocardial performance and coronary flow (CF) compared with control (left ventricular developed pressure: 53 ± 5 vs 27 ± 4 mm Hg; +dP/dt max : 1,025 ± 93 vs 507 ± 85 mm Hg/s; CF: 31 ± 3 vs 22 ± 2 mL/min; p Conclusions . Bradykinin pretreatment may be an important new strategy for improving myocardial protection during heart surgery. The molecular mechanism of action may be similar to those activated by ischemic preconditioning.
Aquatic hotspots: speciation in ancient lakes III

Abstract The conference Speciation in Ancient Lakes (‘SIAL') III was held in Irkutsk, Russia from 2 to 7 September2002.
Cholecystokinin both stimulates and inhibits human food intake

THE hypothesis that gastrointestinal hormone(s) released into the blood during normal digestion should inhibit further food intake is attractive. It has been reported1–4 that injection of cholecystokinin (CCK) inhibited eating in rats and rhesus monkeys. We now report that intravenous infusion of CCK in a dose which produces physiological effects ascribed to CCK during normal digestion stimulated, rather than inhibited, eating in man. In contrast, rapid intravenous injection of CCK inhibited human food intake.
Scale height of the Jovian current sheet

Abstract We discuss the parameter D in the Goertz et al. (1979) magnetic field model as it relates to the scale height of the current sheet.
Durability Prediction for GFRP Reinforcing Bars using Short-Term Data of Accelerated Aging Tests

This paper presents a procedure based on the Arrhenius relation to predict the long-term behavior of glass fiber-reinforced polymer (GFRP) bars in concrete structures, based on short-term data from accelerated aging tests. GFRP reinforcing bars were exposed to simulated concrete pore solutions at 20, 40, and 60°C. The tensile strengths of the bars determined before and after exposure were considered a measure of the durability performance of the specimens. Based on the short-term data, a detailed procedure is developed and verified to predict the long-term durability performance of GFRP bars. A modified Arrhenius analysis is included in the procedure to evaluate the validity of accelerated aging tests before the prediction is made. The accelerated test and prediction procedure used in this study can be a reliable method to evaluate the durability performance of FRP composites exposed to solutions or in contact with concrete.
On open membranes, cosmic strings and moduli stabilization

Abstract We discuss how cosmic strings can be created in heterotic M-theory compactifications with stable moduli. We conclude that the only appropriate candidates seem to be fundamental open membranes with a small length. In four dimensions they will appear as strings with a small tension. We make an observation that, in the presence of the vector bundle moduli, it might be possible to stabilize a five-brane very close to the visible sector so that a macroscopic open membrane connecting this five-brane and the visible brane will have a sufficiently small length. We also discuss how to embed such cosmic strings in heterotic models with stable moduli and whether they can be created after inflation.
Psychosocial and Clinical Correlates of ADHD in a Community Sample of School-Age Children

ABSTRACT Objective To identify the psychosocial and clinical correlates of attention-deficit hyperactivity disorder (ADHD) in a community sample of children and to examine the validity of a subclinical form of ADHD. Method The sample of 449 children (mean age 9.2 years, SD1.78; 53.6% boys) participated in the second stage of a community survey. Of these, 359 (80%) screened positive at stage 1. On the basis of a structured diagnostic interview with a parent, children were classified into 1 of 3 mutually exclusive groups: ADHD ( n = 89), subthreshold ADHD ( n = 100), and non-ADHD ( n = 260). Results As measured by the Children's Global Assessment Scale, the ADHD group was more impaired than the subthreshold group, which was more impaired than the non-ADHD group ( p p p Conclusions These results support a dimensional approach to ADHD. More severe forms of ADHD are associated with psychosocial adversity and psychiatric comorbidity. J. Am. Acad. Child Adolesc. Psychiatry , 1999, 38(8):976–984.
Shock-Free Turbomachinery Blade Design

A computational method for designing shock-free, quasi-three-dimensional, transonic, turbomachinery blades is described. Shock-free designs are found by implementing Sobieczky's fictitious gas principle in the analysis of a baseline shape, resulting in an elliptic solution that is incorrect in the supersonic domain. Shock-free designs are obtained by combining the subsonic portion of this solution with a characteristic calculation of the correct supersonic flow using the sonic line data from the fictitious elliptic solution. This provides a new, shock-free blade design. Examples presented include the removal of shocks from two blades in quasi-three-dimensional flow and the development of a series of shock-free two-dimensional stators. The new designs all include modifications to the upper surface of an experimental stator blade developed at NASA Lewis Research Center. While the designs presented here are for inviscid flow, the same concepts have been successfully applied to the shock-free design of airfoils and three-dimensional wings with viscous effects. The extension of the present method to viscous flows is straightforward given a suitable analysis algorithm for the flow.
Structural Evolution of the Dihydrate to Anhydrate Crystalline Transition of Trehalose as Measured by Wide-angle X-ray Scattering

Wide-angle X-ray scattering measurements were performed to record structural changes during the transition from trehalose dihydrate to crystalline anhydrous alpha-trehalose. The results show that large dihydrate crystals rearrange into smaller sized alpha crystals; from the peak widths we calculate a crystallite size of typically approximately 40 trehalose molecules. We find that the dehydration probably takes place in a two-step process with different time scales for both the water removal step and the molecule rearrangement step. This suggests that there is crystal rearrangement in the dry state some 60 degrees C below the dry glass transition temperature of trehalose, which is unusual for a relatively large and strongly interacting molecule.
Sprengel on the Fertilisation of Flowers

IN NATURE, vol. xxix. p. 29, is a letter from Prof. Hagen of Cambridge, Mass., calling attention to the fact that Sprengel's treatise on the structure and fertilisation of flowers was not unappreciated in his own day. Now it so happened that only a week or two before reading this I took up by chance the “Introduction to Physiological and Systematical Botany,” by Sir James Edward Smith, the American edition, dated 1814. On p. 208 the author says:—
Odor control performance of carbon‐loaded rayon monofilaments

The odor control performance of carbon-loaded rayon monofilaments depends on the type and proportion of activated carbon used. The filter efficiency in turn determines the rate of odor reduction in a closed space and the ultimate or equilibrium concentration when odorant generation and removal occur simultaneously. Four types of filters were evaluated: rayon loaded with air- or water-purification carbon, granular air-purification carbon, and open-lattice commercial filters. Air laden with synthetic tobacco malodor was streamed through successive increments of adsorbent bed. Sensory odor judgments were made before and after each adsorption stage by matching the effluent odors with those from mixtures of known concentrations. It was thus possible to estimate adsorption efficiencies and, by repeating the measurements after various degrees of carbon saturation, to construct adsorption waves. It was found that airpurification carbon was superior to water-purification carbon for loading in the rayon filaments, and that all the rayon-carbon compositions were much superior to the commercial open-lattice filters. The rayon-carbon filters showed efficiencies up to 70% for one pass at 0.1 sec. detention time through a 3/4-in. bed packed at 0.096 g./ml. with a filament comprising 20% rayon and 80% carbon.
The Role of PML in Tumor Suppression

The PML gene, involved in the t(15;17) chromosomal translocation of acute promyelocytic leukemia (APL), encodes a protein which localizes to the PML-nuclear body, a subnuclear macromolecular structure. PML controls apoptosis, cell proliferation, and senescence. Here, we review the current understanding of its role in tumor suppression.
Molecular characterization of an anther-specific gene from tobacco shows sequence similarity to a tapetum-specific gene from tomato

We have cloned and determined the DNA sequence of the cDNA of ntGRP15. The cDNA ntGRP15 represents an anther-specific, developmentally regulated gene from Nicotiana tabacum that encodes a glycine-rich protein. Northern analysis shows that the gene is specifically expressed in anthers and is stringently regulated during anther development. It appears only in anthers at the meiosis to free microspore stages of development. The encoded protein is small (12.2 kDa), has a 31% glycine content and contains a putative signal sequence. By both nucleotide and amino acid sequence alignment, the gene shows high sequence similarity to a gene previously isolated from Lycopersicon esculentum, namely, TomA92b9. High glycine content, presence of a signal sequence and similarity to the tomato TomA92b9 gene suggests the protein functions as a structural cell wall protein, possibly involved in pollen exine formation.
Spin and orbital angular momenta of electromagnetic waves in free space

We derive exact expressions, in the form of Fourier integrals over the (k,{omega}) domain, for the energy, momentum, and angular momentum of a light pulse propagating in free space. The angular momentum is seen to split naturally into two parts. The spin contribution of each plane-wave constituent of the pulse, representing the difference between its right- and left-circular polarization content, is aligned with the corresponding k-vector. In contrast, the orbital angular momentum associated with each plane-wave is orthogonal to its k-vector. In general, the orbital angular momentum content of the wavepacket is the sum of an intrinsic part, due, for example, to phase vorticity, and an extrinsic part, r{sub CM} x p, produced by the linear motion of the center-of-mass r{sub CM} of the light pulse in the direction of its linear momentum p.
Infarction of the gallbladder after celiac arteriography

Abstract A case of infarction of the gallbladder is presented. To our knowledge, this is the first example of this complication occurring after celiac arteriography.
Beta blockade in the compensation for bed-rest cardiovascular deconditioning: physiologic and pharmacologic observations.

Abstract Beta-adrenergic blockade using intravenous propranolol was evaluated as a countermeasure for bed-rest-induced cardiovascular deconditioning. After propranolol administration, tolerance to a maximal lower body negative pressure (LBNP) test after bed rest improved to at least the −70 mm Hg level; following this, there was a sharp decrease in tolerance time. Propranolol decreased mean tolerance time by 36% (17.7 ± 2.4 to 11.5 ± 2.3 minutes) before bed rest, and by only half as much (16.6%) after bed rest (14.4 ± 2.2 to 12.0 ± 2.3 minutes). Systemic vascular resistance was maintained and even slightly increased after propranolol despite a decrease in cardiac output, indicating β 2 -adrenergic blockade. Heart rates at all levels of LBNP were lower during β blockade, yet increases occurred with successive LBNP steps, both before and after bed rest, indicating withdrawal of parasympathetic nervous system influences. Results support the use of propranolol in small dosages as a countermeasure after bed rest, and the findings may also be extrapolated to space-flight deconditioning.
The search for significance: different tests on the same data

In many situations a variety of tests are available to test essentially the same null hypothesis. In practice the statistician who fails to reject with the first test used will sometimes try several others, stopping when he obtains the hoped-for significance. This raises the type I error rate, but no broad study has previously been made to address the question by how much. Here the effect of such multiple testing is investigated by simulating two-sample data and studying five common tests: the t, Wilcoxon-Mann-Whitney,t on logs, Yuen-Dixon trimmed t, and Welch's test.
Maldevelopment of convergence eye movements in macaque monkeys with small- and large-angle infantile esotropia.

PURPOSE To describe symmetric convergence eye movements evoked by disparity and/or accommodative cues in esotropic macaque monkeys, with the goal of determining whether these animals have the vergence deficits found in humans with esotropia. METHODS Physical far and near targets were used to evoke large (approximately 8 degrees) symmetric convergence eye movements in four adult macaque monkeys (two with strabismus, two normal), using positive-feedback rewards. One strabismic monkey had infantile-onset, small-angle esotropia (small-eso approximately 2 degrees) induced by alternating occlusion from birth to age 9 months. The other strabismic monkey had naturally occurring, large-angle (approximately 25 degrees) infantile-onset esotropia (large-eso). Visual acuity was normal in each eye as measured by spatial sweep visually evoked potentials (VEPs). Eye movements were recorded using magnetic search coils. RESULTS When viewing binocularly, both normal monkeys exhibited accurate, stereotyped symmetric convergence movements that achieved 87% to 96% of the required change in vergence angle by the end of the initial movement. In contrast, the small-eso monkey's convergence response when viewing binocularly was variable, strikingly asymmetric, usually accompanied by a disjunctive saccade, and subnormal, achieving only 56% of required vergence. The convergence response of the large-eso monkey was also asymmetric and weak, achieving 18% of the required vergence and employing conjugate saccades to refixate the near target. Monocular viewing (i.e., accommodative vergence) caused substantial reductions in both convergence amplitudes and velocities in the normal monkeys, but had a minor effect on the vergence behavior of the strabismic animals. CONCLUSIONS Monkeys with small- and large-angle infantile esotropia have striking maldevelopments of binocular (disparity-driven) convergence and use accommodative vergence and saccades to refixate near targets. Their vergence behavior resembles that in esotropic humans. The maldevelopment may be explained in large part by the paucity of binocular connections recently described in the visual cortex of esotropic macaques.
Selective missing pulse steady state free precession (MP-SSFP): inner volume and chemical shift selective imaging in a steady state sequence.

Purpose To examine new sequences that restrict acquisition of spins to those excited by both of the RF pulses in missing pulse steady state free precession (MP-SSFP) MRI. Materials and Methods New MP-SSFP sequences were created by replacing one of the slice selective pulses (SSPs) with an orthogonal SSP for inner volume imaging, and with a chemical shift selective (CHESS) pulse for chemical shift imaging. The inner volume sequence was applied to a reduced field of view at the center of a resolution phantom; resulting images were evaluated for differences in the aliased signal. The CHESS sequence was applied to volunteers, as well as to and fat, water, and acetic acid phantoms. Results were evaluated with SNR measurements. Results The inner volume sequence eliminated the aliased signal, while nonselected fat and water levels were suppressed to that of noise by the CHESS sequence. Conclusion Results suggest a novel steady state technique for rapid inner volume or chemical shift imaging. J. Magn. Reson. Imaging 2004;19:124–132. © 2003 Wiley-Liss, Inc.
Differential modulation of chemical and electrical components of mixed synapses in the lobster stomatogastric ganglion.

1. Two pairs of neurons in the pyloric network of the spiny lobster, Panulirus interruptus, communicate through mixed graded chemical and rectifying electrical synapses. The anterior burster (AB) chemically inhibits and is electrically coupled to the ventricular dilator (VD); the lateral pyloric (LP) and pyloric (PY) neurons show reciprocal chemical inhibition and electrical coupling. We examined the effects of dopamine (DA), serotonin (5HT) and octopamine (Oct) on these mixed synapses to determine the plasticity possible with opposing modes of synaptic interaction. 2. Dopamine increased net inhibition at all three pyloric mixed synapses by both reducing electrical coupling and increasing chemical inhibition. This reversed the sign of the net synaptic interaction when electrotonic coupling dominated some mixed synapses, and activated silent chemical components of other mixed synapses. 3. Serofonin weakly enhanced LP → PY net inhibition, by reducing electrical coupling without altering chemical inhibition. Serotonin reduced AB→ VD electrical coupling, but variability in its effect on the chemical component made the net effect non-significant. 4. Octopamine enhanced LP→ PY and PY→ LP net inhibition by enhancing the chemical inhibitory component without altering electrical coupling. 5. Differential modulation of chemical and electrical components of mixed synapses markedly changes the net synaptic interactions. This contributes to the flexible outputs that modulators evoke from anatomically defined neural networks.
Germinal reversion of an unstable mutation for anthocyanin pigmentation in soybean

Plants of the “w4-mutable” line of soybean [Glycine max (L.) Merr.] are chimeral for anthocyanin pigmentation. Mutable plants produce both near-white and purple flowers, as well as flowers of mutable phenotype with purple sectors on near-white petals. It is established here that the mutable trait is conditioned by an unstable recessive allele of the w4 locus that conditions anthocyanin biosynthesis. The gene symbol w4-m is assigned to the mutable allele. Allele w4-m was derived from a stable, wild-type W4 progenitor allele and reverts at high frequency to a stable, wild-type W4 allele. Reversion occurs both early and late during the development of the germ line. Several experiments give estimates of germinal reversion frequency, indicating that approximately 6% of mutable alleles revert to wild-type from one generation to the next. Allele w4-m exhibits many features typical of an allele controlled by a transposable element.
Scene-based Nonuniformity Correction with Video Sequences and Registration

We describe a new, to our knowledge, scene-based nonuniformity correction algorithm for array detectors. The algorithm relies on the ability to register a sequence of observed frames in the presence of the fixed-pattern noise caused by pixel-to-pixel nonuniformity. In low-to-moderate levels of nonuniformity, sufficiently accurate registration may be possible with standard scene-based registration techniques. If the registration is accurate, and motion exists between the frames, then groups of independent detectors can be identified that observe the same irradiance (or true scene value). These detector outputs are averaged to generate estimates of the true scene values. With these scene estimates, and the corresponding observed values through a given detector, a curve-fitting procedure is used to estimate the individual detector response parameters. These can then be used to correct for detector nonuniformity. The strength of the algorithm lies in its simplicity and low computational complexity. Experimental results, to illustrate the performance of the algorithm, include the use of visible-range imagery with simulated nonuniformity and infrared imagery with real nonuniformity.
Structure-activity relationship study of pyridazine derivatives as glutamate transporter EAAT2 activators

Excitatory amino acid transporter 2 (EAAT2) is the major glutamate transporter and functions to remove glutamate from synapses. A thiopyridazine derivative has been found to increase EAAT2 protein levels in astrocytes. A structure-activity relationship study revealed that several components of the molecule were required for activity, such as the thioether and pyridazine. Modification of the benzylthioether resulted in several derivatives (7-13, 7-15 and 7-17) that enhanced EAAT2 levels by >6-fold at concentrations < 5 μM after 24h. In addition, one of the derivatives (7-22) enhanced EAAT2 levels 3.5-3.9-fold after 24h with an EC(50) of 0.5 μM.
On a perturbation theory using Lie transforms

Kamel has recently extended to non-Hamiltonian equations a perturbation theory using Lie transforms. We show here how Kamel's extension can be approached from an intrinsic viewpoint, which reformulation leads to a simpler algorithm. Then we complete Kamel's contribution by establishing the rules for inverting the transformation generated by the perturbation theory, and for composing two such transformations.
Mathematical models of cladogenesis

The evolutionary pattern of speciation and extinction in any biologic group may be described by a variety of mathematical models. These models provide a framework for describing the history of taxonomic diversity (clade shape) and other aspects of larger evolutionary patterns. The simplest model assumes time homogeneity: that is, speciation and extinction probabilities are constant through time and within taxonomic groups. In some cases the homogeneous model provides a good fit to real world paleontological data, but in other cases the model serves only as a null hypothesis that must be rejected before more complex models can be applied. In cases where the homogeneous model does not fit the data, time-inhomogeneous models can be formulated that specify change, regular or episodic, in speciation and extinction probabilities. An appendix provides a list of the most useful equations based on the homogeneous model.
Potentiometric anion response of poly (tetrakis(p‐aminophenyl)porphyrin) film‐modified electrodes

The potentiometric response to anions of glassy carbon electrodes coated with thin unmetallated poly(tetrakis(p-aminophenyl)porphyrin) (poly(H2(p-TAPP))) films is examined. The polymer films are introduced onto the glassy carbon surface by constant-potential anodic electrolysis of the porphyrin monomer from a solution of dichloromethane containing a quaternary ammonium perchlorate salt. The thickness of the film is the controlled by the electrodeposition time. Oxidized poly(porphyrin) modified electrodes exhibit near Nernstian response to iodide in the concentration range of 5 × 10−5 – 1 × 10−1 M with significant selectivity over a wide range of other anions tested. The mechanism of the electrode's iodide ion response is considered in light of its response to other redox-active anions, and a recent literature report describing the selective iodide response of electrodes coated with electropolymerized poly(3-methylthiophene) films. Spectroelectrochemical studies with poly(porphyrin)-modified tin oxide electrodes are used to confirm the redox-type response mechanism of the sensors toward iodide. The analytical limitations of using such polymer film-modified electrodes for potentiometric ion sensing are discussed.
Measuring soil moisture with imaging radars

An empirical algorithm for the retrieval of soil moisture content and surface root mean square (RMS) height from remotely sensed radar data was developed using scatterometer data. The algorithm is optimized for bare surfaces and requires two copolarized channels at a frequency between 1.5 and 11 GHz. It gives best results for kh/spl les/2.5, /spl mu//sub /spl upsi///spl les/35%, and /spl theta//spl ges/30/spl deg/. Omitting the usually weaker hv-polarized returns makes the algorithm less sensitive to system cross-talk and system noise, simplifies the calibration process and adds robustness to the algorithm in the presence of vegetation. However, inversion results indicate that significant amounts of vegetation (NDVI>0.4) cause the algorithm to underestimate soil moisture and overestimate RMS height. A simple criteria based on the /spl sigma//sub hv//sup 0///spl sigma//sub vv//sup 0/ ratio is developed to select the areas where the inversion is not impaired by the vegetation. The inversion accuracy is assessed on the original scatterometer data sets but also on several SAR data sets by comparing the derived soil moisture values with in-situ measurements collected over a variety of scenes between 1991 and 1994. Both spaceborne (SIR-C) and airborne (AIRSAR) data are used in the test. Over this large sample of conditions, the RMS error in the soil moisture estimate is found to be less than 4.2% soil moisture. >
Locating Earthquakes: At What Distance Can the Earth No Longer Be Treated as Flat?

Earthquake location programs for events recorded at regional to teleseismic distances have traditionally used travel-time tables such as the J-B tables (Jeffreys and Bullen, 1958), which were based on ray tracing in a laterally homogeneous spherical earth ( e.g., Boyd et al., 1984). Such travel-time tables may not give accurate locations for events located using stations at local to near-regional distances because of regional variations in the crustal and upper-mantle velocity structure—the regions of the Earth in which the first-arrival P and S waves spend most of their time for such events. Until recently, it was a nontrivial task to create travel-time tables for different spherical-earth velocity structures. Accordingly, for the past 30+ years, most locations for local and near-regionally-recorded events have used programs which used flat-earth ray tracing through constant-velocity layers. Examples of such programs are Hypo71 (Lee and Lahr, 1972), Hypoinverse (Klein, 1985), Fasthypo (Herrmann, 1979), and Hypoellipse (Lahr, 1999). With the advent of digital recording and advances in telemetry, there are an increasing number of data sets which include arrival times for small to medium-sized events at both local and regional distances. Most researchers are aware of the fact that the assumption of lateral homogeneity may be invalid for event-station paths at larger epicentral distances, but when shown results as given in Figure 1 below, seismologists often express surprise that the spherical-earth travel-time corrections became significant ( e.g., > 0.1 s) at what seemed relatively small epicentral distances. The purpose of this paper is to document the limitations of using a flat-earth velocity model to approximate travel times within the earth and to suggest strategies for minimizing errors in the analysis of events which are observed at distances for which the spherical-earth corrections become significant. A review of the math and physics involved in flat-earth and spherical-earth ray …