cssi/SciSciGPT-SciSciNet huggingface dataset:
Magnetic resonance characterization of septal bounce: findings of blood impact physiology

‘Septal bounce’ is a pathognomonic sign of constrictive pericarditis (CP). The objectives of the study are to resolve the etiology of the septal bounce, to generate septal bounce-related diagnostic tools, and to prove that its presence is related to the mechanical interaction between the atrioventricular inflow and the inter-ventricular septum. We compared steady state free precession four-chamber images between 11 CP patients and 11 controls via cardiac magnetic resonance. The septal bounce was composed of two movements observed during every cardiac cycle, simultaneous with the rapid filling and atrial systole respectively. Three parameters (measured at end-systole) were generated: right ventricular (RV) clamp (compression ratio of the RV)—greater in CP (0.88 ± 0.03) than controls (0.85 ± 0.03, p = 0.02), tri-septal angle between the tricuspid valve annulus plane and the interventricular septum (81° ± 9° vs. 91° ± 7°, p = 0.01), and impact angle between the tricuspid inflow vector and septum (8.6° ± 8.7° vs. 0° ± 6.6°, p = 0.01). The accuracy, positive predictive value, sensitivity and specificity of these parameters in differentiating CP from controls ranged from 100 to 82 %. A forth parameter—septal flow ratio, gauging the proportion of tricuspid inflow impacting the septum, was markedly higher in CP than controls (0.38 ± 0.19 vs. 0.01 ± 0.03, p < 0.0001) with 100 % sensitivity, specificity, positive and negative predictive value. The septal bounce consists of two sequential movements during each cardiac cycle, is time-related with the rapid ventricular filling and atrial systole, and likely represents a result of the tricuspid blood inflow impacting the interventricular septum. Four septal bounce-derived parameters have a good accuracy in differentiating CP from volunteers.
Inhibitors of Measles Virus

Measles virus (MV) infections have been almost eradicated in some industrialized nations. However, MV continues to cause severe disease and mortality in the world and is responsible for clusters of exogenous-borne disease in essentially disease-free countries. Because of the ebb and flow of immunization campaigns, especially in the poverty-stricken and war-torn Third World, and the ominous potential for severe disease and mortality, it is vital that research for discovery of therapeutic countermeasures should continue. To that end, a number of compounds have been evaluated for efficacy in vitro and in animal models, and several therapeutic modalities have been tested in the clinic. The only current therapies used in the clinic include ribavirin administered orally or intravenously, alone or in combination with immune serum globulin; these therapies have demonstrated variable efficacy. Therefore, drug discovery efforts have been launched to supplement the existing treatments for MV infections. Antisense molecules, adenosine and guanosine nucleosides, including ring-expanded 'fat' nucleoside analogues, brassinosteroids, coumarins, peptide inhibitors, modulators of cholesterol synthesis and a variety of natural products have been screened for efficacy and toxicity both in vitro and in animals. However, none of these agents has gone into human clinical trials and most will not merit further development due to toxicity concerns and/or low potency. Thus, further research is needed to develop more potent and less toxic drugs that could be used for treating MV infections to supplement the existing MV vaccine campaigns.
Kangaroo Care Increases Breastfeeding Rates

Proposed Change Kangaroo care, or skin-to-skin contact, began in 1979 in Bogota, Columbia, as a way to keep infants warm and provide optimal nutrition following birth. Research has shown that Kangaroo care has many benefits for mothers and infants, including increased breast milk supply and greater breastfeeding success. The American Academy of Pediatrics recommends skin-to-skin contact as a strategy to increase breastfeeding success. In 2007, a Kangaroo care program for healthy infants and their mothers at the University of Louisville Hospital (ULH) was implemented. However, the philosophy was not adopted as a standard of care until 2010. Strategies were developed to hardwire the process and facilitate a change in practice that supported the use of Kangaroo care.
Ferromagnetic domain-wall behavior during reversal and thermally activated antiferromagnetic reversal in an exchange-biased NiO/NiFe bilayer

The magnetization reversal mechanism in an exchange-biased ${\mathrm{N}\mathrm{i}\mathrm{O}/\mathrm{N}\mathrm{i}}_{81}{\mathrm{Fe}}_{19}$ bilayer has been investigated using the magneto-optic Kerr effect and magnetic force microscopy imaging. The asymmetric reversal along the unidirectional axis and the two-step reversal process along the hard axis are promoted by ferromagnetic domain-wall behavior in the decreasing and increasing field branches of the as-deposited hysteresis loop, which is strongly related to the exchange coupling at the interface and the distribution of orientation of the net magnetization at the interface carried by the antiferromagnetic domains. The temperature dependence of the exchange bias and coercivity shows the thermally activated reversal of the net antiferromagnetic magnetization, which improves the unidirectional anisotropy at the interface or induces a new unidirectional axis, depending on whether the measuring field is along the unidirectional or hard axis of the as-deposited sample.
The Most Cited IEEE Software Articles

This paper identifies the most cited IEEE Software articles over its 25 year history. An emerging citation tool is the H-index, defined as the lowest rank at which the number of citations is greater than or equal to the rank. To compute the H-index, we first compute and rank each entity's (author's or journal's) number of citations; the paper with the most citations is ranked first, the one with second-most citations is second, and so on. For example, if the 30th-ranked paper has 30 citations, then its H-index would be 30.
Tool procurement planning for wafer fabrication facilities: a scenario-based approach

The rate of change in technology in the semiconductor industry has made the demand supply planning process extremely challenging for manufacturers. This problem is further exacerbated for tool procurement because the tools are made to order, very expensive and have a long lead time for delivery. In this paper, we present a scenario-based stochastic planning approach for tool procurement under uncertainty in demand and formulate the problem as a mixed integer program. Our results based on the data from a manufacturing line indicate that the heuristics for stochastic planning can significantly outperform deterministic planning.
Capillary Electrophoresis and Fluorescence Anisotropy for Quantitative Analysis of Peptide−Protein Interactions Using JAK2 and SH2-Bβ as a Model System

Fluorescence anisotropy capillary electrophoresis (FACE) and affinity probe capillary electrophoresis (APCE) with laser-induced fluorescence detection were evaluated for analysis of peptide−protein interactions with rapid binding kinetics. The Src homology 2 domain of protein SH2-Bβ (SH2-Bβ (525−670)) and a tyrosine-phosphorylated peptide corresponding to the binding sequence of JAK2 were used as a model system. For peptide labeled with fluorescein, the Kd = 82 ± 7 nM as measured by fluorescence anisotropy (FA). APCE assays had a limit of detection (LOD) of 100 nM or 12 amol injected for SH2-Bβ (525−670). The separation time of 4 s, achieved using an electric field of 2860 V/cm on 7-cm-long capillaries, was on the same time scale as complex dissociation allowing Kd (101 ± 12 nM in good agreement with FA measurements) and dissociation rate (koff = 0.95 ± 0.02 s-1 corresponding to a half-life of 0.73 s) to be determined. This measurement represents a 30-fold higher rate of complex dissociation than what had...
Butyric acid: A small fatty acid with diverse biological functions

Abstract Butyric acid, a 4-carbon fatty acid, affects morphology, growth rate and gene expression in mammalian cells in culture. Sodium butyrate (0.5 to 3 mM) produces reversible growth inhibition in several mammalian tumor cells in culture, but it causes cell death only in human neuroblastomas and human glioma cells in culture. Sodium butyrate in combination with currently used tumor therapeutic agents produced a synergistic, an additive or no effect on growth of mouse neuroblastoma cells and rat glioma cells in culture. At least in NB cells, the cell death and growth inhibition may be related to the reduction in anaerobic glycolysis. Sodium butyrate increases the expression of one or more differentiated functions in mouse NB cells, mouse erythroleukemic cells, human epidermoid carcinoma, human colon carcinoma cells and Chinese hamster ovary cells. The induction of differentiation by butyrate may in part be related to an increase in the cellular cyclic AMP level. Sodium butyrate increases the activities of several enzymes, whereas, it decreases the activities of some. The increase of some enzymes appears to be correlated to hyperacetylation of histones. In vitro studies suggest that sodium butyrate may be useful in the management of neoplasms by causing selective cell death, and/or cell differentiation and by increasing the cell killing effect in conjuction with currently used tumor therapeutic agents. Sodium butyrate can also be used as a tool to study the regulation of gene expression in mammalian cells.
Fracture simulations using large-scale molecular dynamics

We report on recent molecular-dynamics (MD) fracture simulations of mode-I tensile loading at high strain rates. Because cracks emit sound waves, previous simulations became unreliable beyond one sound traversal time. Using massively parallel MD, we show how to eliminate unwanted boundary effects and study unimpeded crack propagation mechanisms. In order to represent tensile stress conditions near the crack tip, we employ uniaxial, homogeneously expanding periodic boundary conditions, examining the effects of strain rate, temperature, and interaction potential. Because our samples are sufficiently large, we see dislocations being emitted from the crack tip at nearly the shear-wave sound speed ${\mathit{c}}_{\mathit{s}}$. As they move many lattice spacings away from the crack, they slow down, finally moving at about 2/3${\mathit{c}}_{\mathit{s}}$. Each time dislocations are emitted, the crack tip ``fishtails,'' and at sufficiently high strain, the crack can fork; dislocations can climb and become nucleation sites for additional microcracks. We find that we can suppress ductile behavior by including viscous damping in the equations of motion, thereby demonstrating a transition to brittle crack propagation as static, zero-strain-rate conditions are approached. Finally, we show that, by altering only the attractive tail of the pair potential, we can change a ductile material into a brittle one. Under dynamic crack propagation, the distinction between ductile and brittle behavior is blurred: in brittle materials, dislocations are asymptotically bound to the crack tip, while in ductile materials, they can escape.
On the development of a catalyst fouling model

Abstract A model of catalyst fouling is presented. It is based on a reaction network in which a hydrocarbon molecule is sequentially adsorbed onto a small group of active sites. Each intermediate species in this sequence is bonded to a different number of sites and treated as an independent fouling precursor. Thus, a series of parallel reactions are competing to foul the surface. The rate of each parallel step differs by an exponential factor equivalent to about 2 kcal/mol decrease in the fouling activation energy for each additional site involved in the rate determining step of fouling, and a simple power-model activity factor. The model provides an explanation of empirical fouling correlations and the apparent “variable reaction order” of fouling. The model is extended to include catalysts that are pretreated by a poisoning agent such as sulfur.
Optical lithography at a 126-nm wavelength

There is a window of opportunity for optical lithography between wavelengths of 100 nm and 157 nm that warrants exploration as a next generation technology. We will present activities underway to explore the feasibility of VUV optical lithography in this region with respect to source, optical design, materials, processes, masks, resolution enhancement, and compatibility with existing technologies. We have constructed a small field prototype lithography system using the second continuum 126nm emission wavelength of the Argon excimer. This has been accomplished using a small dielectric barrier discharge lamp with output on the order of 10mW/cm2 and small field catoptric imaging systems based on a modified Cassegrain system. Capacitance focus gauge and piezo electric stage has been installed for fine focusing. In order to achieve sub-half wavelength resolution that would be required to compete with 157nm lithography and others, we have started exploring the feasibility of using liquefied noble gas immersion fluids to increase effective value of lens numerical aperture by factors approaching 1.4x. Conventional silylation process works well with 126nm with high sensitivity. Chemically amplified DUV negative resist looks very good material for 126 nm. Initial contact printing image shows good selectivity and process control. An effort is also underway to explore the use of inorganic resist materials, as silver halide material for instance, to replace the conventional polymeric imaging systems that are currently employed at longer wavelengths, but may be problematic at these VUV wavelengths. Early accomplishments are encouraging. Prototype optical research tools can be used to reveal issues involved with 126nm lithography and solve initial problems. Though many challenges do exist at this short wavelength, it is quite feasible that lithography at this wavelength could meet the part of the needs of future device generations.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A simple and effective element for analysis of general shell structures

Abstract A simple flat three-node triangular shell element for linear and nonlinear analysis is presented. The element stiffness matrix with 6 degrees-of-freedom per node is obtained by superimposing its bending and membrane stiffness matrices. An updated Lagrangian formulation is used for large displacement analysis. The application of the element to the analysis of various linear and nonlinear problems is demonstrated.
Synthesis, spectroscopic studies and crystal structure analysis of zinc nitrosylpentacyanoferrate trihydrate, ZnFe(CN)5NO·3H2O

Abstract The crystal structure of zinc nitrosylpentacyanoferrate trihydrate has been determined from three dimensional, single-crystal X-ray diffraction data. Final full-matrix least-squares refinement yielded R = 0.028 and R w = 0.028 for 791 unique reflections. ZnFe(CN) 5 NO·3H 2 O contains iron and zinc atomic centers with distorted octahedral symmetries. The compound crystallizes in the rhombohedral space group R 3 (No. 148, C 2 3i ) on a hexagonal lattice, a = 19.305(5) and c = 17.627(5) A, Z = 18, D m = 1.76(1) Mg m −3 and D x = 1.762 Mg m −3 . The lattice constants were obtained from powder diffraction data, F (30) = 38(0.011,69) and M (20)= 30.0. The iron atom is coordinated to five cyanide ligands and one nitrosyl group, while the zinc atom is coordinated to five cyanide ligands and one water molecule. FeC NZn bridging links the metal atoms. Two uncoordinated water molecules, one of which is disordered, occupy channels in the crystal. Optical, infrared, X-ray fluorescence and thermal gravimetric analyses have also been carried out. Important mean bond lengths are: ZnN = 2.110(20), FeC = 1.933(8) and CN = 1.129(6) A. Other notable bond lengths include: ZnO = 2.224(7), FeN= 1.684(9) and NO = 1.102(9) A.
Strontium isotope ratios and base metal content in a core from the Atlantis II deep, Red Sea

Abstract The isotope composition of strontium leached with aqua regia from sediment samples of core 128P from the Atlantis II deep of the Red Sea appears to be very nearly constant between depths of 130 and 795 cm below the top of the core. Twelve of seventeen samples have 87 Sr 86 Sr ratios between limits of 0.7070 and 0.7080. All samples have significantly lower 87 Sr 86 Sr ratios than sea water, which suggests that the sediment was precipitated from brines containing an appreciable component of strontium derived from young basic volcanic or plutonic rocks at depth. A small systematic decrease of the 87 Sr 86 Sr ratio with depth in the Fe-montmorillonite facies appears to correlate inversely with concentrations of copper and zinc. The four sedimentary facies represented in this core have characteristic average concentrations of strontium, copper, and zinc. The highest base metal concentrations occur in the sulfide and Fe-montmorillonite facies.
Indices of Anseriform body shape based on the relative size of major skeletal elements and their relationship to reproductive effort

To assess whether relative clutch mass (RCM) in Anseriformes (wildfowl or waterfowl) is constrained by body shape, principal components (PCs) of size-adjusted measurements of five major skeletal elements of adult males and females of 60 species of Anseriformes provided indices of body shape. PC1 accounted for 69.8% of the variance and contrasted anterior elements (cranium and sternum) to posterior elements (synsacrum, femur and tibiotarsus). PC1 scores were high in species with a ‘duck-like’ body shape and low in those with a ‘goose-like’ body shape. Over the phylogeny of Anseriformes, decreased PC1 scores were associated with feeding on land. PC2 accounted for 18.6% of the variance and contrasted core elements (sternum and synsacrum) with peripheral elements (cranium, femur and tibiotarsus). High PC2 scores were associated with dependence on animal food, particularly in diving species. PC3 accounted for 7.7% of the variance and reflected mainly the relative size of the femur, which was low in diving species. Controlling statistically for phylogenetically independent contrasts in female body shape, there was a significant positive partial correlation between RCM and PC1, suggesting that independent of body size, body shape imposes constraints on reproductive effort in Anseriformes. The results suggest that models of the evolution of reproductive effort in this order, and perhaps in other orders, of birds should control for the effects of body shape.
Expression of Sphingolipid Activator Protein Gene in Brain and Systemic Organs of Developing Mice

The sphingolipid activator proteins (SAPs) are a family of small, heat-stable glycoproteins, proven or postulated to be required for in vivo degradation of some sphingolipids by hydrolytic enzymes. Fo
Abstract 1208: Elucidating possible functional implications of osteosarcoma risk-associated genetic level alterations in IGF2R

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL To address the need for novel osteosarcoma (OS) treatment regimens with greater efficacy and less toxicity, attention has been focused on developing antibodies that target components of the insulin-like growth factor (IGF) pathway, particularly insulin-like growth factor 1 receptor tyrosine kinase (IGF1R). IGF1R and its two ligands, insulin-like growth factor 1 (IGF1) and insulin-like growth factor 2 (IGF2), are known to be over-expressed in several cancers including OS and have roles in regulating cellular growth and proliferation. Clinical trials of IGF1R-inhibiting antibody therapies in OS, however, have returned mixed results. Studies aimed at elucidating the biologic basis of this differential clinical sensitivity to IGF1R-targeting therapeutic agents are currently underway. Interestingly, recent studies from our lab show that IGF2R is consistently over-expressed, relative to other known transmembrane receptors, on the cell surface, across 4 standard and 10 patient-derived OS cell lines. Coupled with results from concurrent experiments suggesting a lack of IGF1R copy number amplification in the majority of tested patient-derived OS samples and xenograft models, we chose to focus our next set of studies on IGF2R_aiming to characterize significant genetic variations within this gene and any functional implications, thereby elucidating the link, if any, between IGF2R's mutational status and its cell surface expression in OS. Relative quantification studies, done via real-time PCR, demonstrated variable IGF2R gene expression across 27 patient-derived OS samples, 4 xenograft models, and 4 standard cell culture (serum-starved) lines. Using the CaCo-2 cell line as the calibrator, 12 out of 27 patient-derived OS samples showed increased IGF2R gene expression, while none of the xenograft models or the standard OS cell lines did. Ongoing studies will examine the relationship between genetic level alterations in IGF2R and its patterns of expression; common IGF2R SNPs will be genotyped, first in the four available OS xenograft models. Findings will be correlated with known patterns of clinical response/sensitivity to IGF1R-targeted therapy tested on these models. The same SNPs will then be genotyped in the patient-derived OS samples and standard cell culture lines. Depending on the results obtained from these initial studies, further experiments can be designed to sequence/genotype other suspect coding regions on the IGF2R gene that may contain functionally significant mutations. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1208. doi:10.1158/1538-7445.AM2011-1208
Loadsa: A yield-driven top-down design method for STT-RAM array

As an emerging nonvolatile memory technology, spin-transfer torque random access memory (STT-RAM) faces great design challenges. The large device variations and the thermal-induced switching randomness of the magnetic tunneling junction (MTJ) introduce the persistent and non-persistent errors in STT-RAM operations, respectively. Modeling these statistical metrics generally require the expensive Monte-Carlo simulations on the combined magnetic-CMOS models, which is hardly integrated in the modern micro-architecture and system designs. Also, the conventional bottom-up design method incurs costly iterations in the STT-RAM design toward specific system requirement. In this work, we propose Loadsa1: a yield-driven top-down design method to explore the design space of STT-RAM array from a statistical point of view. Both array-level semi-analytical yield model and cell-level failure-probability model are developed to enable a top-down design method: The system-level requirements, e.g., the chip yield under power and area constraints, are hierarchically mapped to array-and cell-level design parameters, e.g., redundancy, ECC scheme, and MOS transistor size, etc. Our simulation results show that Loadsa can accurately optimize the STT-RAM based on the system and cell-level constraints with a linear computation complexity. Our method demonstrates great potentials in the early design stage of memory or micro-architecture by eliminating the design integrations, while offering a full statistical view of the design even when the common yield enhancement practices are applied.
Can the Judicial Branch be a Steward in a Polarized Democracy

At the beginning of his first term as Chief Justice, John Roberts pledged to try to persuade his colleagues to consider the bipartisan legitimacy of the Court rather than their own ideological agendas. Roberts had mixed success during his first years on the bench, as the Court handed down a series of highprofile decisions by polarized, 5–4 votes. In the health care decision, however, Roberts did precisely what he said he would do, casting a tie-breaking vote to uphold the Affordable Care Act because he thought the bipartisan legitimacy of the Court required it. But the reaction to the health care decision – which Democrats approved and Republicans did not – suggests that Roberts's task of preserving the Court's bipartisan legitimacy is more complicated than he may have imagined, and that his success in the future will depend on the willingness of his colleagues to embrace his vision. Given the Court's declining approval ratings, an increase in partisan attacks on the Court, and a growing perception that t...
Tautomerism of singly protonated chloroquine and quinacrine

Differential absorptiometric pH titrations of the antimalarials chloroquine and quinacrine, employing the respective uncharged species at pH 12.5 in the reference cell, show that protolytic dissociation from the heterocyclic ring nitrogen atoms occurs over pH 6–12. This finding indicates that the singly charged cations of the drugs exist measurably in two tautomeric forms. The tautomeric equilibrium constants were calculated from the titration data. The existence of these tautomeric equilibria may have significance in the pharmacodynamics of chloroquine and quinacrine.
Aspectos a conocer de la medicina intensiva en Estados Unidos

There exist profound differences in the training and professional duties of intensive care physicians and the way intensive care units are managed between the United States and Europe and particularly Spain. Some of the remarkable characteristics of intensive care medicine in the united states include the application process for residency, continuing evaluation during training, phased training with employability at every level, competency based training, scientific research as a core value during training and medical practice, and clinical activity reaching beyond the intensive care unit to include regular hospital wards and ambulatory clinics. The characteristics of intensive care units and the role of intensive care physicians are flexible and change according to the needs of the hospitals where they are located.
Absorption of different elemental diets in a short-bowel syndrome lasting 15 years.

In a patient with total colectomy and only 120 cm of the proximal small bowel remaining after resection for Crohn's disease, comparative studies were performed on the absorption of isocaloric amounts of Vivonex HN, Flexical, Codelid, Jejunal, and Precision LR. These elemental and/or complete diets were fed by a nasogastric tube at a constant rate of 260 ml/hr, 1 cal/ml, 2185–2660 ml per feeding period of 8.4–10.2 hr daily. Discharge of intestinal fluids from the jejunal stoma ranged between 2940 ml (Vivonex HN) to 4760 ml (Jejunal) per daily feeding period, resulting in a net intestinal loss of fluids and dehydration with the exception of Flexical. Jejunostomy discharge on Flexical was only 1325 ml per comparable period. The patient tolerated dietary fat relatively well absorbing 61% of 87 g of fat from Flexical and 60% of 108 g from a natural blenderized diet. The other diets used were either fat-free or with a minimum amount of fat. The second best tolerated diet was Vivonex HN, the feeding of which resulted in the highest intestinal retention of nitrogen (84% of the 16.3 g fed as opposed to 78% of 9.1 g fed in Flexical). Vivonex HN also had the highest intestinal retention of phosphorus. Intestinal fluid absorption was not related to the intestinal transit time measured by a nonabsorbable marker or to the osmolality of diets. Diets containing fat may inhibit secretion by the “enterogastrone-like” effect induced by dietary fat in the remaining bowel. High amino acid content of some of the low-fat diets may release gastrointestinal hormones which stimulate secretion, and the simple carbohydrates prevent fluid absorption. In the short-bowel syndrome with normal functions of the pancreaticobiliary system, diets based on fat and protein hydrolysate should be the nutritional therapy of choice.
Direct and Inverse Addition in Convex Analysis: The Continuous Case

Abstract We study the direct and inverse sum of order p of a family {ifAw: w ϵ Ω} of sets in some finite dimensional linear space. The discrete case Ω = {1,2} has been studied in a previous work of the author. In the present paper the indexing set Ω is infinite. Applications to the theory of electrical synthesis and to the theory of nonsmooth convex functions are considered.
Dental education and practice in the 21st century: Opportunities for excellence

This study describes the environment that can be expected for dental education and dental practice as the 21st century approaches. The study uses data from many sources, including the recent report from the Institute of Medicine, which provides a comprehensive analysis of the variables that will affect dental education and practice in the next decade. Dental education and practice will be able to thrive if the new forces are carefully examined and the challenges are met promptly.
Heat transfer in a rotating cylinder of fluid heated from above

Abstract We present a mathematical analysis of centrifugally driven thermal convection in a cylinder which rotates about its vertical axis. Two extensions are made of previous work. First, a heat flux through the side wall of the cylinder is considered and its effect on the Nusselt number for the top and bottom cylinder surfaces is determined. Secondly, a constant heat flux boundary condition for the horizontal surface is investigated.
Application of autoradiographic techniques to studies of shoot apices.

IN contrast to the earlier widely accepted concepts of the structure and growth of the shoot apex, Buvat and his associates1–3 have proposed an alternative interpretation. According to this newer view the most apical, axial cells of shoot apices in a variety of plants do not have histogenic or organogenic roles during vegetative growth. The criterion of activity was based on the frequency of mitosis. This information was obtained by counting mitotic figures in various zones of the shoot apex and then presenting this information in the form of a composite diagram. The results of these investigations have been challenged by Gifford4 and by Popham5; the latter used essentially the same methods as did the French workers.
Rapid bioassay of aluminum toxicity in soil

Fifty-five acid soil horizons from 19 profiles were evaluated for aluminum toxicity using root elongation as a criterion in a two-day petri dish bioassay. The method proved to be simple, efficient, and precise enough to clearly distinguish aluminum toxicity differences among horizons within and between profiles. Although toxicity patterns within profiles differed, it was common for surface horizons to be less toxic even when very acid. The R2 for correlations of relative root lengths with pH in H2O, pH in KCl, soluble and exchangeable aluminum and percent aluminum saturation were only 0.42, 0.45, 0.52, 0.66, and 0.54, respectively, which indicates the need for a bioassay. In a further use of the method, and to demonstrate its efficiency, 243 horizons from 26 profiles were screened. Approximately half of the horizons with a pH of 5.0 or below showed Al toxicity. When used by different operators, with a variety of soil and treatment parameter changes, the two-day bioassay in petri dishes gave consistent rankings of soils by degree of aluminum toxicity.
Refractoriness as a determinant of tachycardia inducibility in the right ventricle.

Abstract The use of more than one right ventricular site for programmed electrical stimulation has been reported to increase the number of patients in whom ventricular tachycardia can be provoked. To determine a possible reason for these observations, programmed ventricular tachycardia studies were evaluated in 316 patients (185 men and 131 women) with a mean age of 63 ± 7 years who presented with ventricular tachycardia or cardiac arrest. The underlying cardiac disease was atherosclerosis (81%), cardiomyopathy (15%), valvular heart disease (3%), and miscellaneous conditions (1%). Programmed electrical stimulation studies employed a six-beat pacing train, at a cycle length of 500 msec with the introduction of one to three premature stimuli at twice diastolic threshold at the right ventricular apex. If ventricular tachycardia at the right ventricular apex could not be provoked in a patient, the study was repeated at the right ventricular outflow tract. A total of 36 patients were studied at the right ventricular outflow tract. Eleven (31%) were provoked into ventricular tachycardia, while 25 (69%) were not. No difference existed between the QRS, QT, and QT c intervals between those having ventricular tachycardia provoked at the outflow tract compared to those without inducible tachycardia at the right ventricular outflow tract. The effective refractory period was 280 ± 5 msec at the right ventricular outflow tract in those patients not inducible, and 226 ± 4 msec in those inducible ( p p
P450BM-3: reduction by NADPH and sodium dithionite.

Abstract Microsomal P450s catalyze the monooxygenation of a large variety of hydrophobia compounds, including drugs, steroids, carcinogens, and fatty acids. The interaction of microsomal P450s with their electron transfer partner, NADPH-P450 reductase, during the transfer of electrons from NADPH to P450, for oxygen activation, may be important in regulating this enzyme system. Highly purified Bacillus megaterium P450BM-3 is catalytically self-sufficient and contains both the reductase and P450 domains on a single polypeptide chain of approximately 120,000 Da. The two domains of P450BM-3 appear to be analogous in their function and homologous in their sequence to the microsomal P450 system components. FAD, FMN, and heme residues are present in equimolar amounts in purified P450BM-3 and, therefore, this protein could potentially accept five electron equivalents per mole of enzyme during a reductive titration. The titration of P450BM-3 with sodium dithionite under a carbon monoxide atmosphere was complete with the addition of the expected five electron equivalents. The intermediate spectra indicate that the heme iron is reduced first, followed by the flavin residues. Titration of the protein with the physiological reductant, NADPH, also required approximately five electron equivalents when the reaction was performed under an atmosphere of carbon monoxide. Under an atmosphere of argon and in the absence of carbon monoxide, one of the flavin groups was reduced prior to the reduction of the heme group. The titration behavior of P450BM-3 with NADPH was surprising because no spectral changes characteristic of flavin semiquinone intermediates were observed. The results of the titration with NADPH can only be explained if (a) there was “rapid” intermolecular electron transfer between P450BM-3 molecules, (b) there is no kinetic barrier to the reduction of P450 by the one-electron-reduced form of the reductase, and (c) the “air-stable semiquinone” form of the reductase does not accumulate in this complex multidomain enzyme.
Grey-level image hiding scheme based on vector quantisation

A novel image hiding scheme capable of hiding multiple grey-level images into another grey-level cover image is proposed. To reduce the volume of secret images to be embedded, the vector quantisation scheme is employed to encode the secret images. The compressed message is then encrypted by the DES cryptosystem to ensure security. Finally, the encrypted message is hidden into the cover image using the greedy least significant bit substitution technique.
Full length article: On higher order boundary derivatives of an analytic self-map of the unit disk

Characterization of Schur-class functions (analytic and bounded by one in modulus on the open unit disk) in terms of their Taylor coefficients at the origin is due to I. Schur. We present a boundary analog of this result: necessary and sufficient conditions are given for the existence of a Schur-class function with the prescribed nontangential boundary expansion f(z)=s"0+s"1(z-t"0)+...+s"""N(z-t"0)^N+o(|z-t"0|^N) at a given point t"0 on the unit circle.
Magnetically insulated linac driven by a multistage Marx generator

It is shown that a magnetically insulated linear accelerator driven by a multistage Marx generator can accelerate over short distances intense beams of heavy ions to multi-GeV energies. The attainable beam energies are sufficient for the ignition of thermonuclear microexplosions. The proposed accelerator could also ideally serve as a research tool for heavy ion induced nuclear reactions.
Advances in microwave power transmission

Power transmission by microwaves has a long history of technology development and key demonstrations. By 1975 the improvements in component conversion efficiencies (DC-to-RF and RF-DC) increased the end-to-end system efficiency from 13% to 54%. These early S-band wireless power transmission (WPT) demonstrations proved this concept as a viable form of power transmission to ground, air, and space platforms. Whereas they emphasized high power, low frequency, and long distance power beaming, recent applications have focused on relatively shorter distances and lower power over a wide range of frequencies. These applications include powering personal electronics and unmanned aerial vehicles along with energy harvesting from radiated RF emissions. WPT technology development, demonstrations, and studies have occurred at microwave and millimeter-wave frequencies. In all applications, high transmitter and rectenna efficiencies are required to minimize heat dissipation and maximize the end-to-end efficiency. High power, high efficiency solid-state amplifiers have been developed to allow phased array antenna transmitters to electronically steer the power beam to single or multiple rectennas. Thin and lightweight rectennas have been developed that are efficient, polarization agile, and conformable to a platform's structure. Along with these topics, the history, key demonstrations, WPT concepts, applications, and technology updates are discussed.
Carbohydrates and nitrogenous compounds in the honeydew of the mustard aphid, Lipaphis erysimi

Abstract The chemical composition of the leaf sap of the radish, a host plant for the mustard aphid, Lipaphis erysimi , is compared with the composition of the honeydew that is excreted. The results indicate that the aphid utilizes sugars in a descending order of glucose, pentose sugars, fructose, and dextrins. Dextrin is utilized in very small amounts if at all and there is some evidence that the dextrin from honeydew has a larger molecule than the dextrin in the plant sap. Nitrogenous excretory products, when compared with the leaf sap materials, indicate the utilization of the essential amino acids and the elimination of nitrogen principally as arginine. Urea was detected and there were traces of ammonium salts. Amides and carbamyl compounds occur in significant concentrations high enough to indicate that the excretory mechanism of the aphid could be severely taxed to provide for their elimination.
The Development, Validity, and Reliability of a Psychometric Instrument Measuring Competencies in Student Affairs.

AbstractThe study of competencies in student affairs began more than 4 decades ago, but no instrument currently exists to measure competencies broadly. This study builds upon previous research by d...
Housing mobility programs and economic self-sufficiency: Evidence from a randomized experiment

This paper examines the effects of a randomized housing-voucher program on individual economic outcomes. Public housing residents who are offered relocation counseling together with housing vouchers that can only be redeemed in low-poverty areas experience a reduction in welfare receipt of between 11% and 16% compared to controls. These effects are not accompanied by changes in earnings or employment rates as measured by unemployment insurance records. Offering families unrestricted housing vouchers without additional counseling appears to have little effect on economic outcomes.
MESOAMERICAN LANDSCAPE ARCHAEOLOGIES

Landscapes figure centrally in conceptions and writings about ancient Mesoamerica. This selective review considers four interrelated kinds of landscapes investigated archaeologically in Mesoamerica: ecology and land use, social history, ritual expression, and cosmologic meaning. The literature on each topic is large, and from its inception, Ancient Mesoamerica has contributed significantly. Discussion here focuses on how we got to where we are in Mesoamerican landscape archaeology, important current developments, and directions for the decades ahead.
Cerium oxide nanoparticles protect gastrointestinal epithelium from radiation-induced damage by reduction of reactive oxygen species and upregulation of superoxide dismutase 2.

Abstract The ability of rare earth cerium oxide (CeO 2 ) nanoparticles to confer radioprotection against gastrointestinal epithelium was examined. The pretreatment of normal human colon cells (CRL 1541) with varying concentrations of CeO 2 nanoparticles 24 hours before single-dose radiation exposure conferred protection from radiation-induced cell death by reducing the amount of reactive oxygen species produced and increasing the expression of superoxide dismutase 2 (SOD2), in a dose-dependent manner. In subsequent experiments athymic nude mice were pretreated with intraperitoneal injections of CeO 2 nanoparticles before a single dose of radiation to the abdominal area. Immunohistochemical analysis show a decrease in TUNEL-and caspase 3–positive cells in the colonic crypt, 4 hours after radiation. In sharp contrast, a significant increase in SOD2 expression was observed. In the end, these studies suggest that CeO 2 nanoparticles protect the gastrointestinal epithelium against radiation-induced damage by (1) acting as free-radical scavengers and (2) increasing the production of SOD2 before radiation insult. From the Clinical Editor In this study, the ability of rare earth cerium oxide (CeO 2 ) nanoparticles to confer radioprotection was examined. The results suggest that CeO 2 nanoparticles protect the gastrointestinal epithelium against radiation-induced damage both by acting as free-radical scavengers and by increasing the production of SOD2 before radiation insult.
Controlled ovulation of the dominant follicle: a critical role for LH in the late follicular phase of the menstrual cycle

BACKGROUND: A method was sought to control ovulation of the dominant follicle and to test the importance of LH during the late follicular phase of the menstrual cycle. Menstrual cycles of rhesus monkeys were monitored, and treatment initiated at the late follicular phase (after dominant follicle selection, before ovulation). METHODS: The 2-day treatment consisted of GnRH antagonist plus either r-hFSH and r-hLH (1:1 or 2:1 dose ratio) or r-hFSH alone. In addition, half of the females received an ovulatory bolus of hCG. RESULTS: When treatment was initiated at estradiol levels >120 pg/ml, neither the endogenous LH surge, ovulation nor luteal function were controlled. However, when treatment was initiated at estradiol levels 80‐120 pg/ml using either 1:1 or 2:1 dose ratios of FSH:LH, the LH surge was prevented, and ovulation occurred following hCG treatment. FSH-only treatment also prevented the LH surge, but follicle development appeared abnormal, and hCG failed to stimulate ovulation. CONCLUSIONS: Control over the naturally dominant follicle is possible during the late follicular phase using an abbreviated GnRH antagonist, FSH+LH protocol. This method offers a model to investigate periovulatory events and their regulation by gonadotrophins/local factors during the natural menstrual cycle in primates.
Dual orthogonal matrices in manipulator kinematics

The angular or linear displacements required at each of the joints of a robot manipulator to attain a specified position and orientation of its hand are obtained by solving the closure equations of the manipulator. These equations express the fact that the sequence of coordinate transformations between each link of the manipulator from its hand to its base must equal the transformation from the hand to the base directly. It is well known that the 4 X 4 homogeneous form of the point coordinate transformation matrix together with special coor dinate frames adapted to the structure of a manipulator yield a standard form of these coordinate transformation matrices known as the Denavit-Hartenberg matrix (Paul 1981). It is not so well known that the transformation equations of the coordinates of lines in these special coordinate frames may be used as well (Pennock and Yang 1985). Furthermore, by introducing dual numbers, the 6 X 6 matrices that arise col lapse into 3 X 3 orthogonal matrices with dual number ele...
Point-of-care testing improves accuracy of STI care in an emergency department

Objectives We aimed to examine the impact of a point-of-care (POC) test on overtreatment and undertreatment of sexually transmitted infections (STIs) by comparing treatment patterns for gonorrhoea (detected with nucleic acid amplification testing (NAAT)) with trichomoniasis (detected by POC test) for young women seen in an emergency department (ED). Methods We reviewed the database of a quality improvement (QI) project that aims to improve follow-up care for STIs in the ED. Data included the test result and antibiotic given (if any) during visits by women age 14–21 for whom an STI test was ordered. We generated Shewhart control charts and compared overtreatment and undertreatment rates for gonorrhoea and trichomoniasis using χ 2 testing. Results Of 1877 visits over 18 months, 8.8% of women had gonorrhoea and 16.5% had trichomoniasis. Overtreatment was higher for women with gonorrhoea than trichomoniasis (54% vs 23%, p Conclusions A POC test improves the accuracy of STI care in an ED compared with NAAT testing. An unanticipated benefit of QI efforts to improve patient follow-up is the observed decrease in antibiotic use in the ED. Given the ability of gonorrhoea to develop antibiotic resistance, future efforts should focus on development of an accurate POC test for gonorrhoea.
Technical Note: Crevice Effect on Corrosion of Steel in Simulated Concrete Pore Solutions

Abstract Effect of a crevice on the breakdown potentials (Eb) of carbon steel specimens in pH 12.6 saturated calcium hydroxide (Ca[OH]2) solution (SCS) and pH 13.6 simulated concrete pore solution (SPS) with 0.01 M to 1.0 M chloride concentration ([Cl−]) was studied with potentiodynamic polarization. The presence of a crevice substantially lowered (by ∼ 0.2 V) the Eb in SCS when [Cl−] ≥ 0.1 M. In SPS, passive film breakdown did not take place up to the oxygen evolution potential (OEP) in the absence of a crevice. However, corrosion developed in the crevice at potentials ∼ 0.5 V below the OEP when a crevice was introduced and [Cl−] ≥ 0.1M.