cssi/SciSciGPT-SciSciNet huggingface dataset:
Representation of solid-liquid equilibrium of aqueous electrolyte systems with the electrolyte NRTL model

Abstract Solid-liquid equilibrium of aqueous electrolyte systems is characterized with wide electrolyte concentration and temperature ranges, common ion effects, ionic equilibrium reactions, multiple hydrate formation, double salt precipitation, etc. This paper discusses the application of the electrolyte NRTL model for solid-liquid equilibrium of aqueous electrolyte systems. Successful results demonstrate the usefulness of the model for representing solid-liquid equilibrium of aqueous electrolyte systems.
Lidocaine prophylaxis in coronary revascularization patients: A randomized, prospective trial

Abstract Life-threatening ventricular ectopy can occur after cardiac operations. The actual incidence of ventricular ectopy and the ability to prevent it by the routine prophylactic use of lidocaine hydrochloride have not been established. We performed a double-blind, randomized, prospective trial involving 109 patients undergoing elective coronary artery revascularization. Patients received either lidocaine (n = 54) or a placebo (n = 55) after separation from bypass. A Holter monitor was affixed to each patient for subsequent review, and bedside intensive-care monitors with alarms were used for "real-time" surveillance. The code was broken when potentially malignant ventricular ectopy or side effects attributable to the study drug were noted. Three lidocaine patients and 2 placebo patients were dropped from the study because of hemodynamic instability or bleeding. Of the remaining 104 patients, the code was broken in 12 (24%) of the 51 in the lidocaine group (9 for ectopy and 3 for mental status changes) and 10 (19%) of the 53 in the placebo group (all for ectopy) ( p = not significant). Twenty-four-hour Holter monitor evaluation demonstrated occasional ventricular ectopy in all patients and nonsustained ventricular tachycardia in 28% in the lidocaine group and 48% in the placebo group ( p = not significant). The mean number of runs of ventricular tachycardia per patient was 0.53 in the lidocaine group and 1.6 in the placebo group ( p = 0.035). There were no significant differences in terms of other ventricular ectopy, morbidity, or mortality. No ventricular fibrillation occurred in either group. We conclude that although prophylactic administration of lidocaine may decrease the incidence of nonsustained ventricular tachycardia in patients undergoing routine coronary revascularization, there is no apparent clinical benefit to such a strategy. Lidocaine should be used for treatment of high-grade ventricular ectopy rather than as prophylaxis.
Platinized Chloroplasts: A Novel Photocatalytic Material

Colloidal platinum was prepared and precipitated directly onto photosynthetic thylakoid membranes from aqueous solution and entrapped on fiberglass filter paper. This composition of matter was capable of sustained simultaneous photoevolution of hydrogen and oxygen when irradiated at any wavelength in the chlorophyll absorption spectrum. Experimental data support the interpretation that part of the platinum metal catalyst is precipitated adjacent to the photosystem I reduction site of photosynthesis and that electron transfer occurs across the interface between photosystem I and the catalyst. Photoactivity of the material was dependent on the nature of the ionic species from which the platinum was precipitated. All photoactive samples were prepared from the hexachloroplatinate(IV) ion, whereas samples prepared by precipitation of the tetraammineplatinum(II) ion showed no hydrogen evolution activity and only transient oxygen activity. This system is among the simplest known for photosynthetically splitting water into molecular hydrogen and oxygen.
The Influence of Release Strategy and Migration History on Capture Rate of Oncorhynchus mykiss in a Rotary Screw Trap

Abstract Rotary screw traps are used in rivers throughout the west coast of North America to capture emigrating juvenile salmonids. Calibrating the capture efficiency of each trap is essential for valid estimates of fish passage. We released PIT-tagged Oncorhynchus mykiss upstream of a rotary screw trap in the South Fork John Day River, Oregon, to estimate capture efficiency. We used three strategies for release of fish recently captured in the trap. We recaptured 28% of medium-sized fish (86–145 mm FL) and 14% of large-sized fish (146–230 mm FL) released during daylight 1.6 km upstream from the trap. We recaptured 33% of medium-sized fish and 17% of large-sized fish released during daylight 4.8 km upstream from the trap. We recaptured 42% of medium-sized fish and 23% of large-sized fish released at twilight 1.8 km upstream from the trap. A PIT tag antenna detected summer-tagged parr (which were PIT-tagged upstream 1–5 months before migration) as they approached the trap to evaluate potential bias from re...
Brain cell membrane Na+,K(+)-ATPase activity following severe hypoxic injury in the newborn piglet.

This study tests the hypothesis that severe brain hypoxia causes decreased Na+,K+-ATPase activity, resulting in permanent alterations in the neuronal cell membranes. Seventeen anesthetized piglets (normoxic control (NC), no recovery after hypoxia (Group 1), 6 h normoxic recovery (Group 2), and 48 h normoxic recovery (Group 3) were studied. Hypoxia was induced by lowering the FiO2 to maintain PCr/Pi ratio at 25% of baseline for 1 h as monitored by 31P-NMR spectroscopy. PCr/Pi returned to 57% of baseline by 6 h and was normal by 48 h. At termination, cortical tissue Na+,K+-ATPase activity was determined. Na+,K+-ATPase activity was measured in cortical membrane preparations by determining the rate of ATP hydrolysis. NC membranes had Na+,K+-ATPase activity of 58.3 ± 1.3 μM Pi/mg protein/h (mean ± S.E.M.). Na+,K+-ATPase activity was reduced in Groups 1, 2, and 3 (45.8 ± 1.3, 47.4 ± 3.6, 48.7 ± 2.9 μM Pi/mg protein/h) (P < 0.05 compared to NC). There was no differene in enzyme activity among Groups 1, 2, or 3. The data show that in spite of recovery of neuronal oxiditive phosphorylation (PCr/Pi) by 48 h, there is a permanent decrease in Na+,K+-ATPase activity in cells that have undergone severe hypoxic injury. The persistent decrease in Na+,K+-ATPase activity indicates ongoing cell injury following severe cerebral hypoxia, and that recovery of oxidative phosphorylation as indicated by PCr/Pi values cannot be used as an index of recovery of cell function.
Radial and solar cycle variations of the magnetic fields in the heliosheath: Voyager 1 observations from 2005 to 2008

[1] We discuss the magnetic field strength B(t) and polarity observed by Voyager 1 (V1) in the heliosheath at the heliographic latitude ≈34° as it moved away from the Sun from 2005 through 2008.82 (where 2008.0 is the beginning of 1 January 2008). The pattern of the polarity of the magnetic field changed from alternating positive and negative polarities to predominantly negative polarities (magnetic fields pointing along the Archimedean spiral field angle toward the Sun) at ≈2006.23). This transition indicates that the latitudinal extent of the heliospheric current sheet (HCS) was decreasing in the supersonic solar wind, as expected for the declining phase of the solar cycle, and as predicted by extrapolation of the magnetic neutral line near the photosphere to the position of V1. However, the polarity was not uniformly negative in during 2008, in contrast to the predicted polarity. This difference suggests that the maximum latitudinal extent of the HCS was tending to increase in the northern hemisphere in the heliosheath, while it was decreasing in the supersonic solar wind. The large-scale magnetic field strength B(t) was observed by V1 from 2005 through 2008.82. During this interval of decreasing solar activity toward solar minimum, B(t) at 1 AU was decreasing, and the solar wind speed V at the latitude of V1 was increasing. Adjusting the temporal profile of B(t) observed by V1 for the solar cycle variations of B and V in the supersonic solar wind, we find that the radial gradient of B(R) in heliosheath from the radial distance R = 94.2 AU to 107.9 AU between 2005.0 and 2008.82 was 0.0017 nT/AU ≤ grad B ≤ 0.0055 nT/AU, or grad B = (0.0036 ± 0.0019) nT/AU.
Microwave-assisted rapid and simplified hydrogenation

Catalytic transfer hydrogenation has been conducted under microwave irradiation in open vessels using high-boiling solvents such as ethylene glycol (bp 198 °C) as the microwave energy transfer agent. Reduction of double bonds and hydrogenolysis of several functional groups were carried out safely and rapidly (3−5 min) at about 110−130 °C with 10% Pd/C as an efficient catalyst and ammonium formate as the hydrogen donor. Diverse types of β-lactam synthons were prepared by the reduction of ring substituents containing alkene and alkylidene groups or conjugated unsaturated esters. Cleavage of the β-lactam ring by hydrogenolysis of the N−C4 bond of 4-aryl-2-azetidinones was a facile reaction with 10% Pd/C as the catalyst; but no ring scission occurred when Raney nickel catalyst was employed. Dehalogenation of aromatic compounds was also successful with ammonium formate and Pd/C catalyst. Hydrogenolysis of phenylhydrazone of methyl benzoylformate gave the methyl ester of phenylglycine in excellent yield. The te...
Nearedge absorption spectroscopy of interplanetary dust particles

Interplanetary Dust Particles (IDPs) are derived from primitive Solar System bodies like asteroids and comets. Studies of IDPs provide a window onto the origins of the solar system and presolar interstellar environments. We are using Total Reflection X-ray Fluorescence (TXRF) techniques developed for the measurement of the cleanliness of silicon wafer surfaces to analyze these particles with high detection sensitivity. In addition to elemental analysis of the particles, we have collected X-ray Absorption Near-Edge spectra in a grazing incidence geometry at the Fe and Ni absorption edges for particles placed on a silicon wafer substrate. We find that the iron is dominated by Fe2O3.
Flow-Dependent Mass Transfer May Trigger Endothelial Signaling Cascades

It is well known that fluid mechanical forces directly impact endothelial signaling pathways. But while this general observation is clear, less apparent are the underlying mechanisms that initiate these critical signaling processes. This is because fluid mechanical forces can offer a direct mechanical input to possible mechanotransducers as well as alter critical mass transport characteristics (i.e., concentration gradients) of a host of chemical stimuli present in the blood stream. However, it has recently been accepted that mechanotransduction (direct mechanical force input), and not mass transfer, is the fundamental mechanism for many hemodynamic force-modulated endothelial signaling pathways and their downstream gene products. This conclusion has been largely based, indirectly, on accepted criteria that correlate signaling behavior and shear rate and shear stress, relative to changes in viscosity. However, in this work, we investigate the negative control for these criteria. Here we computationally and experimentally subject mass-transfer limited systems, independent of mechanotransduction, to the purported criteria. The results showed that the negative control (mass-transfer limited system) produced the same trends that have been used to identify mechanotransduction-dominant systems. Thus, the widely used viscosity-related shear stress and shear rate criteria are insufficient in determining mechanotransduction-dominant systems. Thus, research should continue to consider the importance of mass transfer in triggering signaling cascades.
The Changing World of Home Technology: A Microsoft Case Study

We have entered the “digital decade,” when advances in technology will become deeply woven into home life. But how will technology evolve from an experience that is technologically challenging to an experience that is intuitive and fun? This article reviews new technologies and related possibilities that Microsoft is envisioning in the context of home life. As a specific example of the impact of home technology, we review lessons learned from the adoption and integration of a home Internet device from a user experience perspective. Looking ahead to the next decade, we then take a look at Microsoft's vision for the home of the future, examining new directions.
Beliefs and attitudes about opioid prescribing and chronic pain management: Survey of primary care providers

Objective: There is growing concern of medication misuse and noncompliance among patients with chronic pain prescribed opioids for pain. The aim of this survey was to obtain information from primary care providers (PCPs) about their perception of prescribing opioids for patients with chronic pain . Methods: PCPs were invited to complete a packet of questionnaires about attitudes and concerns about opioids for chronic pain. These questionnaires included 1) General Health Questionnaire, 2) Test of Opioid Knowledge (TOK), 3) Opioid Therapy Provider Survey, and 4) Concerns About Analgesic Prescription Questionnaire . Results: Fifty-six (N = 56) PCPs from eight centers participated in this study. In general, the PCPs showed adequate opioid knowledge on the KOT and their general health was unrelated to prescription attitudes. Most expressed concern about medication misuse (89 percent) and felt that managing patients with chronic pain was stressful (84 percent). Most were worried about addiction (82 percent) and less than half felt that they were sufficiently trained in prescribing opioids (46 percent). Younger providers felt more reluctant to prescribe opioids, experienced more stress in managing patients with pain, had less overall confidence in managing patients with pain, and worried more about opioid dependence than older providers (p < 0.05). Younger providers were also less knowledgeable about opioids, but opioid knowledge was not found to be related to concerns about analgesic prescriptions . Conclusion: This study indicates a general concern and reluctance of primary care physicians to manage the prescribing of opioids among their patients with chronic pain and younger providers expressed more concern about opioids than older providers .
In Vivo and In Vitro Analysis of Factor Binding Sites in Jaagsiekte Sheep Retrovirus Long Terminal Repeat Enhancer Sequences: Roles of HNF-3, NF-I, and C/EBP for Activity in Lung Epithelial Cells

Jaagsiekte sheep retrovirus (JSRV) is the causative agent of ovine pulmonary adenocarcinoma, a contagious lung cancer of sheep that arises from type II pneumocytes and Clara cells of the lung epithelium. Studies of the tropism of this virus have been hindered by the lack of an efficient system for viral replication in tissue culture. To map regulatory regions important for transcriptional activation, an in vivo footprinting method that couples dimethyl sulfate treatment and ligation-mediated PCR was performed in murine type II pneumocyte-derived MLE-15 cells infected with a chimeric Moloney murine leukemia virus driven by the JSRV enhancers (DeltaMo+JS Mo-MuLV). In vivo footprints were found in the JSRV enhancers in two regions previously shown to be important for JSRV long terminal repeat (LTR) activity: a binding site for the lung-specific transcription factor HNF-3beta and an E-box element in the distal enhancer adjacent to an NF-kappaB-like binding site. In addition, in vivo footprints were detected in two downstream motifs likely to bind C/EBP and NF-I. Mutational analysis of a JSRV LTR reporter construct (pJS21luc) revealed that the C/EBP binding site is critical for LTR activity, while the putative NF-I binding element is less important; elimination of these sites resulted in 70% and 40% drops in LTR activity, respectively. Electrophoretic mobility shift assays using nuclear extracts from MLE-15 murine Clara cell-derived mtCC1-2 cells with probes corresponding to the NF-I or C/EBP sites revealed several complexes. Antiserum directed against NF-IA, C/EBPalpha, or C/EBPbeta supershifted the corresponding protein-DNA complexes, indicating that these isoforms, which are also important for the expression of several cellular lung-specific genes, may be important for JSRV expression in lung epithelial cells.
Social isolation and saccharin consumption by the rat.

Abstract Sixteen female rats were deprived of water, and housed either singly (social isolation) or in one large group. Social isolation was hypothesized to produce exaggerated normal responding. Therefore, a saccharin solution, previously shown to be less acceptable than water to deprived rats, should be ingested in lesser amounts by the isolates than by the grouped animals. As predicted, the isolates drank significantly less than the grouped animals on the first presentations of saccharin, and they never drank more saccharin than the grouped animals.
Evaluation of parathyroid hormone as a functional biological marker of rat laryngeal transplant rejection.

Objectives/Hypothesis Short-term immunosuppressive protocols in a preclinical rat model that have led to prolonged survival of the graft in preliminary trials were investigated. Rat allografts, by their heterotopic nature, do not allow direct examination or functional interpretation. The primary objective of the study was to identify a reliable functional biological marker allowing monitoring of graft status. A secondary goal was to use this marker to indicate onset of rejection. Study Design The authors elected to study rat parathyroid hormone as a functional marker of laryngotracheal complex rejection. Theoretically, a pulsed immunosuppressive regimen that is administered when parathyroid hormone levels begin to fall could prevent rejection. Methods Eleven Lewis recipient rats underwent parathyroidectomy one week before laryngeal transplantation. Parathyroid hormone levels were obtained on various days following transplantation, then analyzed with an intact rat parathyroid hormone assay. Animals were killed on different days to allow for comparison of parathyroid hormone levels with histopathological signs of rejection. Results All animals had undetectable levels of parathyroid hormone before transplantation. By 24 hours after transplantation, parathyroid hormone levels were within normal range. At 72 hours, the parathyroid hormone levels dropped precipitously. Rejection of parathyroid glands paralleled the early histological changes of rejection seen in the other anatomical areas of interest in the laryngotracheal graft. Conclusion The study represents the first time a hematological marker has been identified that has predictive value for rejection of transplanted rat larynges. As such, it not only enables a 3-month experimental window with reasonable numbers of animals, but also opens the door for novel sequencing of immunosuppressive modalities.
Assessment and treatment of children's headaches from a developmental perspective.

SYNOPSIS Childhood headache is a common pediatric problem. Clinical researchers have evaluated several behavioral treatments, such as biofeedback and relaxation training, that may be viable interventions. Adding a developmental perspective to the evaluation and treatment of childhood headache is a likely way to increase the effectiveness of these strategies. This paper presents developmental issues related to the assessment and treatment of childhood headache. Three major areas of development are examined and the impact of these areas on the treatment and assessment of headache are discussed. The three major areas are cognitive development, self-regulation and psychosocial development. Provided are practical suggestions for the application of child development principles to assessment and intervention practices that may be more developmentally appropriate.
Serum Inhibin Concentrations before and during Gonadotropin Treatment in Men with Hypogonadotropic Hypogonadism: Physiological and Clinical Implications

We measured by RIA the inhibin concentrations in the sera of 20 men with hypogonadotropic hypogonadism before and during treatment with gonadotropins in order to determine the role of gonadotropins in the control of inhibin secretion and the utility of the serum inhibin concentration in assessing the spermatogenic response to gonadotropin treatment in these patients. Before treatment the mean serum inhibin concentration in the 20 hypogonadotropic men as a group (391 +/- 49 U/L) was significantly lower (P less than 0.001) than that in 27 normal men (741 +/- 52 U/L). In the 7 men whose hypogonadism was of postpubertal onset, the mean serum inhibin concentration (559 +/- 69 U/L) was not significantly lower than that in normal men. In the 13 men whose hypogonadism was of prepubertal onset, the serum inhibin level was significantly lower [381 +/- 74 U/L (P less than 0.01) in the 7 without a history of cryptorchidism and 207 +/- 46 U/L (P less than 0.01) in the 6 with a history of cryptorchidism]. All 20 patients were azoospermic or severely oligospermic and had distinctly subnormal serum testosterone concentrations, even those whose serum inhibin values were normal. In the 7 patients with postpubertal hypogonadism, treatment with hCG alone for 6 months increased the serum testosterone concentration and maximum sperm count to normal, even though the previously normal inhibin concentration was not increased further. In the 13 patients with prepubertal hypogonadism, treatment with hCG alone increased the serum inhibin concentration, and combined treatment with hCG and human menopausal gonadotropin (hMG) increased inhibin further, to well within the normal range (742 +/- 143 U/L) in the patients without a history of cryptorchidism and to just within the normal range (487 +/- 96 U/L) in those with such a history. In the 7 patients with prepubertal hypogonadism but no history of cryptorchidism, treatment with hCG and hMG increased the maximum sperm count to normal in 5. In the 6 patients with prepubertal hypogonadism who did have a history of cryptorchidism, hCG and hMG treatment produced a normal sperm count in only 1. Of 12 patients whose serum inhibin level was more than 300 U/L before treatment, 11 developed a normal maximum sperm count in response to treatment, but of 8 patients whose inhibin concentration was less than 300 U/L before treatment, only 2 developed a normal sperm count in response to treatment (P less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)
Topics in biomedical optics: introduction

The field of biomedical optics is experiencing tremendous growth. Biomedical technologies contribute in the creation of devices used in healthcare of various specialties (ophthalmology, cardiology, anesthesiology, and immunology, etc.). Recent research in biomedical optics is discussed. Overviews of meetings held at the 2002 Optical Society of America Biomedical Topical Meetings are presented.
Force Measurement of Embryonic System Using In Situ PVDF Piezoelectric Sensor

The objective of this paper is to investigate the force behavior of living Drosophila embryos using an in situ PVDF (Polyvinylidene Fluoride) piezoelectric micro-force sensor with resolution in the range of sub-?N. The Drosophila embryo is one of the most studied organisms in biological research, medical research, genetics and developmental biology, and has implications in the cure of human diseases. For a highly efficient and accurate microinjection of genetic material into a Drosophila embryo, it is absolutely necessary to allow close monitoring of the magnitude and direction of microinjection and other biomanipulation forces acting on the embryo during the injection process. In this paper, a networked microrobotic biomanipulation platform integrating a two-axis (2-D) PVDF micro-force sensing tool is used to implement force sensing and injection of living Drosophila embryos. Ultimately, the technology will provide a critical and major step towards the development of automated biomanipuation for batch injection of living embryos in genetics, which will facilitate the development of medicine for the cure of human diseases.
Visual interpretation of complex data

With increasingly complex digital simulations and computations, larger volumes of output are generated, and users must select a concise method of displaying the output and extracting relevant information. A set of imaging functions and display modes is developed to interpret data effectively for a wide range of applications. The imaging functions are complementary. Each function is useful for a different aspect of data interpretation. The relationships between variables and the global structures within the data are obtained with different display modes such as multiple windows and animation. With this set of complementary imaging functions and display modes, more information is obtained than with prior imaging methods. Also, more complex simulation studies are feasible since the results can now be visualized.
Early Osmotic History of the Plasma Membrane

The following topics, among others, are conisidered: Pfeffer's hypothesis of an invisible plasma membrane, to account for similarities in the osmotic behavior of plant cells and artificial osmometers; early doubts as to the reality of Pfeffer's membrane; denial by colloid chemists of the existence of plasma membranes because of the supposed failure of cells to obey osmotic laws; demonstrations of thin, external cell membranes by electrical and micromanipulative methods; use of the plasma membrane in the mathematical treatment of cell permeability; the nature of so-called "perfect osmometers"; the erythrocyte as an osmometer; hemolytic evidence of the existence of an erythrocyte membrane.
Interpolation theorem for diameters of spanning trees

We give an algorithmic approach for transforming any spanning tree of a 2-connected graph into any other spanning tree of the graph. At each step of the transformation we obtain a spanning tree whose diameter differs from that of the previous tree by at most one. Thus if a 2-connected graph G has a as the minimum and b as the maximum diameter of a spanning tree, then for any integer c between a and b , graph G has a spanning tree of diameter c .
Top manager and network effects on the adoption of innovative management practices: a study of TQM in a public hospital system

This paper reports findings from a study that combined two theoretical perspectives—top manager and network/institutional—to examine the factors influencing organizations to adopt innovative management practices. The study setting was a system of public hospitals and the innovation was Total Quality Management (TQM). Study results indicate that both top manager and network/institutional factors are important determinants of whether and when organizations adopt innovations. However, as predicted, the relative importance of these two sets of factors appears to change as an innovation becomes more widely diffused. Copyright © 2001 John Wiley & Sons, Ltd.
Endogenous Cell Seeding Remnant Endothelium After Stenting Enhances Vascular Repair

Background Endothelial integrity is essential for maintaining vascular homeostasis, and endothelial denudation results in neointimal thickening. Balloon-expandable endovascular stents provide a luminal scaffolding within atherosclerotic arteries with minimal direct contact between balloon and endothelium. We wondered whether stents cause diminished endothelial ablation, and if so, whether the degree of endothelial damage might determine later proliferative sequelae. Methods and Results Stainless steel stents were expanded in normal or previously denuded iliac arteries of New Zealand White rabbits. Stented arteries were harvested 15 minutes, 1 hour, 3 days, or 14 days later. En face staining of the luminal surfaces of stented arteries demonstrated that endothelial cell loss began immediately after stent expansion and was restricted to interstices between stent struts. Remnant endothelium adjacent to struts provided the foundation for complete endothelial regeneration of the stented segment within 3 days. B...
Simple electrostatic model for the I — A approximation

Employing the approximation which replaces r ij −1 by (ri+rj)−1 we derive the relation 2ζ/4l+5=I−A where ζ is the orbital exponent of a Slater AO. This semiempirical relation appears to agree with experiment for the cases compared.
pH Affects Marsh Grapefruit Pectinesterase Stability and Conformation

Thermolabile pectinesterase (TL-PE) and thermostable pectinesterase (TS-PE) of Marsh grapefruit were purified by ion-exchange and affinity chromatography. The effect of pH on stability and solvent ...
Inhibition of adrenergic neurotransmission in ischaemic regions of the canine left ventricle

To test hypothesis that adrenergic neurotransmission is impaired in acute myocardial ischaemia, we studied contractile function of normal and ischaemic myocardium after coronary artery occlusion. For each area we compared the contractile response to left sympathetic nerve stimulation (LSS) with the response to exogenous noradrenaline (NA). Contractile response was measured with intramyocardial sonomicrometers. LSS increased aortic pressure and heart rate. NA was infused to achieve an aortic pressure equivalent to LSS and simultaneous atrial pacing matched the heart rate during LSS. In normal zones both interventions produced increased shortening equivalently. In ischaemic zones systolic expansion was unchanged during LSS, while NA improved contractile function of the same zones by decreasing systolic expansion. These responses occurred during ischaemia produced by either anterior or posterior descending coronary occlusion. Changes in regional blood flow, measured by 8 μm radiolabelled microspheres, could not account for the difference between the ischaemic regional response to LSS or NA. We conclude that acute regional ischaemia impairs adrenergic nerve transmission.
Application of a Validated Method for the Determination of Provitamin A Carotenoids in Indonesian Foods of Different Maturity and Origin

Provitamin A carotenoids were measured using a validated high-performance liquid chromatography method in a number of selected leafy vegetables of different maturity and origin, sweet potatoes, and mangos from Indonesia. Mean provitamin A content per 100 g of edible portion was 492 retinol equivalents (RE) for water spinach (Ipomoea aquatica; n = 8), 640 RE for spinach (Amaranthus viridis; n = 8), 1776 RE for cassava leaves (Manihot utulissima; n = 8), 992 RE for papaya leaves (Carica papaya; n = 9), 1889 RE for sweet shoot leaves (Sauropus androgynus; n = 4), 289 RE for jointfir spinach (Gnetum gemon; n = 2), 6 RE for sweet potato (Ipomoea batatas; n = 22), and 250 RE for mango (Mangifera indica; n = 11). Provitamin A content was significantly higher in dark green (mature) leaves (24% on average) than in young leaves. Leafy vegetables collected on the market had significantly lower levels of provitamin A compared to those of field samples (19% on average). Provitamin A content for most, but not all, vege...
Vision and cognition: Drawing the line

Pylyshyn defends a distinction between early visual perception and cognitive processing. But exactly where should the line between vision and cognition be drawn? Our research on object identification suggests that the construction of an object's visual description is isolated from contextually derived expectations. Moreover, the matching of constructed descriptions to stored descriptions appears to be similarly isolated.
A two-compartment model of pulmonary nitric oxide exchange dynamics

The relatively recent detection of nitric oxide (NO) in the exhaled breath has prompted a great deal of experimentation in an effort to understand the pulmonary exchange dynamics. There has been very little progress in theoretical studies to assist in the interpretation of the experimental results. We have developed a two-compartment model of the lungs in an effort to explain several fundamental experimental observations. The model consists of a nonexpansile compartment representing the conducting airways and an expansile compartment representing the alveolar region of the lungs. Each compartment is surrounded by a layer of tissue that is capable of producing and consuming NO. Beyond the tissue barrier in each compartment is a layer of blood representing the bronchial circulation or the pulmonary circulation, which are both considered an infinite sink for NO. All parameters were estimated from data in the literature, including the production rates of NO in the tissue layers, which were estimated from expe...
A reduced multistage architecture for ATM networks

A novel communication switch architecture for ATM (asynchronous transfer mode) networks is presented. The speed of the proposed switch architecture is clock-rate-dependent. This architecture has a modular structure and provides a pipeline activity which reduces head-of-line blocking. As a result of using this architecture, the number of stages required is one half the number of stages used in switches today. This results in a reduction of delay to a maximum of 100% for the ideal case and to 20% on average and a reduction in throughput delay of 25% for the nonideal case when compared with a Banyan network. Because of its high degree of modularity, the architecture can be easily implemented using VLSI techniques. >
Towards ab initio Device Design: The Quasiparticle Self-Consistent GW Approximation

Most materials properties of interest are governed by the behavior of the electrons. They directly participate in almost all electrical, magnetic and optical properties, and are responsible for the forces acting on nuclei, which affects structural and mechanical response. In this talk, I will briefly outline the present status of ab initio electronic structure theory, that is systematic methods to obtain effective one-body Hamiltonians which govern the electronic equations of motion, starting from first principles. I will present a newly developed quasiparticle self-consistent GW (QSGW) approximation, and show that it can generate very accurate one-body Hamiltonians, and is therefore a suitable engine for build device simulators from first principles.
From austerity to prosperity? Migration and child poverty among Mainland and Island Puerto Ricans

Analyses of migrants’ economic circumstances typically use the native-born in the destination as a comparison group. We use the 1990 Census Public Use Microdata Samples for the United States and Puerto Rico to demonstrate the benefits of a comparative approach that includes data from both the origin and the destination. Specifically, the primary objective is to determine how and why the risk of child poverty is associated with migration from Puerto Rico to the United States. The results show that migration reduces the risk of child poverty, partly because better jobs are available on the mainland. Employment, human capital, family structure, and public assistance cannot completely explain observed differences. The results also show that the economic benefits of migration continue for the native-born on the mainland and that return migration to Puerto Rico is associated with impoverishment.
Versatility in Corrinoid Salvaging and Remodeling Pathways Supports Corrinoid-Dependent Metabolism in Dehalococcoides mccartyi

Corrinoids are cobalt-containing molecules that function as enzyme cofactors in a wide variety of organisms but are produced solely by a subset of prokaryotes. Specific corrinoids are identified by the structure of their axial ligands. The lower axial ligand of a corrinoid can be a benzimidazole, purine, or phenolic compound. Though it is known that many organisms obtain corrinoids from the environment, the variety of corrinoids that can serve as cofactors for any one organism is largely unstudied. Here, we examine the range of corrinoids that function as cofactors for corrinoid-dependent metabolism in Dehalococcoides mccartyi strain 195. Dehalococcoides bacteria play an important role in the bioremediation of chlorinated solvents in the environment because of their unique ability to convert the common groundwater contaminants perchloroethene and trichloroethene to the innocuous end product ethene. All isolated D. mccartyi strains require exogenous corrinoids such as vitamin B(12) for growth. However, like many other corrinoid-dependent bacteria, none of the well-characterized D. mccartyi strains has been shown to be capable of synthesizing corrinoids de novo. In this study, we investigate the ability of D. mccartyi strain 195 to use specific corrinoids, as well as its ability to modify imported corrinoids to a functional form. We show that strain 195 can use only specific corrinoids containing benzimidazole lower ligands but is capable of remodeling other corrinoids by lower ligand replacement when provided a functional benzimidazole base. This study of corrinoid utilization and modification by D. mccartyi provides insight into the array of strategies that microorganisms employ in acquiring essential nutrients from the environment.
Learning a model of speaker head nods using gesture corpora

During face-to-face conversation, the speaker's head is continually in motion. These movements serve a variety of important communicative functions. Our goal is to develop a model of the speaker's head movements that can be used to generate head movements for virtual agents based on a gesture annotation corpora. In this paper, we focus on the first step of the head movement generation process: predicting when the speaker should use head nods. We describe our machine-learning approach that creates a head nod model from annotated corpora of face-to-face human interaction, relying on the linguistic features of the surface text. We also describe the feature selection process, training process, and the evaluation of the learned model with test data in detail. The result shows that the model is able to predict head nods with high precision and recall.
Characterization and cation exchange properties of zeolite synthesized from fly ashes

Zeolite P was formed from class F fly ash under hydrothermal conditions. The fly ash was reacted with 2.8 or 5 M NaOH at 100 °C. Zeolite of the above type was produced regardless of the NaOH concentration or the addition of quartz, thus indicating its formation over a wide range of conditions. The zeolite produced was of the NaP-type with a fibrous morphology. Analysis of the pore structure of this zeolite by the BET method indicates a type II isotherm. The specific surface areas of synthesized zeolites increased from 28.5 to 41.1 m2/g when the NaOH concentration was increased from 2.8 to 5.0 M. This zeolite showed a significant selectivity for the uptake of Cs and Sr. Cs uptake ranged from 7.67 to 8.61 meq/100 g while that of Sr ranged from 9.8 to 10.54 meq/100 g. The value obtained depended on the specific synthesis conditions. These values are higher than those observed for tobermorite prepared from the same fly ash even though the tobermorite exhibited a higher specific surface area.
A Survey of Multitasking Behaviors in Organizations

Individual and organizational differences in multitasking have been largely ignored by previous research. As both individual employee and organizational characteristics exert unique and important influences on an organizational system, this study tentatively explores relationships between multitasking and individual differences and organizational outcomes. The individual differences include age, gender, personality, position in organization, tenure with employer, and industry. Organizational outcomes include commitment, job satisfaction, and pay satisfaction. A survey was administered to graduate students and alumni in an Executive MBA program, and an undergraduate business degree program. The study found that multitasking behaviors are widely occurring in the workplace, but employees’ perceptions about multitasking conflict with their reported behavior. The results indicate that the productivity losses from multitasking and interruptions are substantial, yet very few companies provide training on how to multitask effectively. The findings also provide evidence of a possible generational component in multitasking effectiveness.
The Behaviour of the Centres of Activity of Saturated Surfaces during the initial stages of Unimolecular Reactions

The theory of catalytic action recently advanced qualitatively by Pease, Taylor, Armstrong and Hilditch, Constable, which the author has endeavoured to treat quantitatively, is extended in this paper to the explanation of the effect of pressure and inert diluents on catalytic action on saturated surfaces. The results are shown to be in agreement with experiment, and further inferences may be made concerning the relative mean lives of the reactant and the diluent on the surface.
The effect of school on overweight in childhood: gain in body mass index during the school year and during summer vacation.

Objectives. To determine whether school or nonschool environments contribute more to childhood overweight, we compared children’s gains in body mass index (BMI) when school is in session (during the kindergarten and first-grade school years) with their gains in BMI when school is out (during summer vacation). Methods. The BMIs of 5380 children in 310 schools were measured as part of the Early Childhood Longitudinal Study, Kindergarten Cohort. We used these measurements to estimate BMI gain rates during kindergarten, summer, and first grade. Results. Growth in BMI was typically faster and more variable during summer vacation than during the kindergarten and first-grade school years. The difference between school and summer gain rates was especially large for 3 at-risk subgroups: Black children, Hispanic children, and children who were already overweight at the beginning of kindergarten. Conclusions. Although a school’s diet and exercise policies may be less than ideal, it appears that early school environments contribute less to overweight than do nonschool environments. (Am J Public Health. 2007;97:696‐702. doi:10. 2105/AJPH.2005.080754)
Centrifugal Dewatering and Reconstitution of Fine Coal: The GranuFlow Process

This paper describes the continuous bench-scale testing of the GranuFlow Process, developed and patented by the Pittsburgh Energy Technology Center (PETC) of the U.S. Department of Energy. Testing was conducted on both high-g force solid-bowl and screen-bowl centrifuges for dewatering and reconstitution of fine-clean-coal slurry at 300 Ib/h (136 kg/hr) in PETC7's Coal Preparation Process Research Facility. In the GranuFlow Process, fine-clean-coal slurry was treated with a bitumen emulsion before dewatering in both centrifuges. In one example, the treated products from a solid-bowl centrifuge appeared to be dry and in a free-flowing granular form, while the untreated products were wet, lumpy, sticky, and difficult to handle. Specifically, test results from the solid-bowl centrifuge indicated that the moisture content, handleability, and dust reduction of the dewatered coal product improved as the addition of emulsion increased from 2 wt% to 8 wt%. The improvement in handleability was most visible for the ...
The unsteady quasi-vortex-lattice method with applications to animal propulsion

In the early theoretical study of aquatic animal propulsion either the two-dimensional theory or the large aspect-ratio theory has been generally used. Only recently has the unsteady lifting-surface theory with the continuous loading approach been applied to the study of this problem by Chopra & Kambe (1977). Since it is well known that the continuous loading approach is difficult to extend to general configurations, a new quasi-continuous loading method, applicable to general configurations and yet accurate enough for practical applications, is developed in this paper. The method is an extension of the steady version of Lan (1974) and is particularly suitable for predicting the unsteady lead-edge suction during harmonic motion.The method is applied to the calculation of the propulsive efficiency and thrust for some swept and rectangular planforms by varying the phase angles between the pitching and heaving motions. It is found that with the pitching axis passing through the trailing edge of the root chord and the reduced frequency k equal to 0·75 the rectangular planform is quite sensitive in performance to the phase angles and may produce drag instead of thrust. These characteristics are not shared by the swept planforms simulating the lunate tails. In addition, when the pitching leads the heaving motion by 90°, the phase angle for nearly maximum efficiency, the planform inclination caused by pitching contributes to the propulsive thrust over a large portion of the swept planform, while, for the rectangular planform, only drag is produced from the planform normal force at k = 0·75. It is also found that the maximum thrust is not produced with maximum efficiency for all planforms considered. The theory is then applied to the study of dragonfly aerodynamics. It is shown that the aerodynamically interacting tandem wings of the dragonfly can produce high thrust with high efficiency if the pitching is in advance of the flapping and the hindwing leads the forewing with some optimum phase angle. The responsible mechanism allows the hindwing to extract wake energy from the forewing.
EmBOINC: An emulator for performance analysis of BOINC projects

BOINC is a platform for volunteer computing. The server component of BOINC embodies a number of scheduling policies and parameters that have a large impact on the projects throughput and other performance metrics. We have developed a system, EmBOINC, for studying these policies and parameters. EmBOINC uses a hybrid approach: it simulates a population of volunteered clients (including heterogeneity, churn, availability, reliability) and it emulates the server component; that is, it uses the actual server software and its associated database. This paper describes the design of EmBOINC and validates its results based on trace data from an existing BOINC project.
TIMING OF SYNAPTIC TRANSMISSION

Many behaviors require rapid and precisely timed synaptic transmission. These include the determination of a sound's direction by detecting small interaural time differences and visual processing, which relies on synchronous activation of large populations of neurons. In addition, throughout the brain, concerted firing is required by Hebbian learning mechanisms, and local circuits are recruited rapidly by fast synaptic transmission. To achieve speed and precision, synapses must optimize the many steps between the firing of a presynaptic cell and the response of its postsynaptic targets. Until recently, the behavior of mammalian synapses at physiological temperatures was primarily extrapolated from studies at room temperature or from the properties of invertebrate synapses. Recent studies have revealed some of the specializations that make synapses fast and precise in the mammalian central nervous system at physiological temperatures.
DEFEATERS AND HIGHER-LEVEL REQUIREMENTS

Internalists tend to impose on justification higher-level requirements, according to which a belief is justified only if the subject has a higher-level belief (i.e., a belief about the epistemic credentials of a belief). I offer an error theory that explains the appeal of this requirement: analytically, a belief is not justified if we have a defeater for it, but contingently, it is often the case that to avoid having defeaters, our beliefs must satisfy a higher-level requirement. I respond to the objection that external-ists who endorse this error theory will be forced to accept a radical form of scepticism.