cssi/SciSciGPT-SciSciNet huggingface dataset:
Apostasiads, systematic anatomy, and the origins of Orchidaceae

Abstract Anatomical study of several species of the putatively primitive orchids Apostasia and Neuwiedia was based on specimens of leaves, stems and roots. Research was carried out in the hope of providing objective information from anatomy towards unravelling the relationships of these plants, and especially towards answering the question of whether extant orchids evolved from these two genera, or from plants like them. The morphology of Apostasia and Neuwiedia has evoked the dogma of primitiveness because of the two or three anthers borne on separate filaments and the free style and stigma which characterize the flowers. In most other orchids there is only one anther and filaments and styles are fused to form the column (gynostemium). The general anatomical structure of apostasiads shows features present in other orchids; none is restricted to Apostasia and Neuwiedia . Tracheary anatomy, however, shows vessels in roots, but not in any part of the shoot system. Vessel members arc characterized by chiefly simple perforation plates in contrast with other orchids where scalariform perforation plates predominate in vessel members of the root. These phenomena, considered from the phylogenetic standpoint, would cast serious doubt on the possibility that plants with scalariform perforation plates, the ancestral, or primitive condition, could have arisen from plants with simple perforation plates, the derived, or advanced condition. On this basis the apostasiads could not have given rise to the di- and monandrous orchids. Of the several suggested origins for orchids, Hypoxidaceae, or plants similar to them, whether in Asparagales, Liliales or Haemadorales of different authors, could have been the progenitors of orchids as a group, including the apostasiads. Because of the unique combination of floral features in the apostasiads, their predominantly simple perforation plates, and their overall anatomical similarity to orchids in general, it would appear appropriate to consider them as a subfamily, Apostasioideae, of Orchidaceae sensu lato.
Accumulations of naphthalene and cadmium after simultaneous ingestion by the black sea bass, Centropristis striata.

Black sea bass,Centropristis striata, were daily force-fed capsules containing oyster,Crassostrea virginica, tissues previously exposed to109Cd in the presence and absence of14C-naphthalene (NPH). Black sea bass were sacrificed at 24, 72, and 336 hr, and values for radioactivity associated with Cd and total NPH compounds (including NPH cellular metabolites) determined for various tissues and body fluids. Results indicated that concentrations of tissue Cd were significantly higher when both Cd and NPH were ingested simultaneously. Tissue concentrations of total NPH compounds were generally not affected by the presence of Cd.
Liver and bile duct pathology following Cryptosporidium parvum infection of immunodeficient mice

Patients with acquired immune deficiency syndrome (AIDS) and boys with mutations of the CD154 gene (causing congenital X-linked immunodeficiency with hyper-IgM [XHIM]) are susceptible to chronic infections of the biliary tract with Cryptosporidium parvum (CP) that may lead to biliary sclerosis and ultimately to cholangiocarcinoma. To determine whether the CP infection and the consequent immune response contribute independently to this morbidity, we infected mice with severe combined immunodeficiency (SCID) or with disrupted genes for CD154, CD40, or interferon gamma (IFN-gamma) with CP. Even when CP infection persisted for 16 weeks, the SCID mice developed only mild triaditis, without apoptosis of biliary epithelial cells (BEC). Fifty percent of the CD154 knockout mice developed lobular hepatitis with acute and chronic triaditis. The CD40 knockout mice developed marked triaditis, and the IFN-gamma knockouts either succumbed to enteritis or survived to develop marked triaditis, portal fibrosis, biliary sclerosis, necrosis with dilation of duct-like structures within the porta hepatis, and dysplastic changes. CP-infected SCID mice reconstituted with T cells from IFN-gamma knockout donors either developed severe enteritis or survived to develop triaditis, cholangitis, lobular hepatitis with periductular sclerosis, and scarring. Mice with disruptions of both the CD40 and IFN-gamma genes remained infected by CP and developed bile duct and liver disease, but not enteritis. Our results suggest that T-cell cytokines are required for the inflammatory and sclerosing responses to CP infection in immunodeficient animals. The response of immunodeficient mice to CP infection may model at least the initial steps toward the development of sclerosing cholangitis or bile duct cancers in XHIM patients.
Effect of hydrocarbon chain length on the uncoupling of photophosphorylation by amines.

Abstract The effectiveness of normal aliphatic amines in uncoupling photophosphorylation in chloroplasts increases dramatically with increasing number of carbon atoms. A similar effect was observed in subchloroplast particles, except that phosphorylation in these preparations was less sensitive to inhibition by aliphatic amines with less than five carbon atoms than phosphorylation in chloroplasts. A linear relationship between the log of the concentration of the amines required to give 50% inhibition of photophosphorylation and the log of their octanol/water partition coefficients was obtained for ethyl- through hexyl-amines. A similar relationship was found for hexylthrough nonyl-amines except that the inhibition increased more dramatically with increasing chain length than for the shorter chain amines. In contrast, the log of the activity of the amines in the inhibition of hydrogen ion uptake in chloroplasts was linearily related to the log of their octanol/water partition coefficients for all amines tested. The trypsin-activated, Ca2+-dependent adenosine triphosphatase of purified coupling factor 1 from chloroplasts was insensitive to inhibition by short chain amines, but was strongly inhibited by long chain amines. The dependency of the inhibition of this reaction by amines on their hydrocarbon chain length was similar to that observed in the inhibition of phosphorylation. The inhibition of photophosphorylation by long chain amines may, therefore, be caused in part by their effects on coupling factor 1. Phosphorylation in subchloroplast particles supplemented with valinomycin is inhibited by ammonium chloride. In the presence of these reagents, phosphorylation in subchloroplast particles may be stimulated by amines. The effectiveness of amines in stimulating phosphorylation under these conditions paralleled their effectiveness as uncouplers. This observation provides evidence that this stimulatory action of the amines is related to their action as uncouplers.
Planetary System Evolution and the Vega Stars: The Potential for Esa’s Infrared Space Observatory

ESA’s Infrared Space Observatory [ISO], scheduled for launch within the next 2–3 years, will place a complement of powerful infrared imagers and spectrometers into high orbit, with an operational life anticipated to be about 18 months. During this time, numerous scientific investigations of every conceivable astrophysical target will be made. The purpose of this paper is to consider the instrumental complement in terms of specific observations of Vega-like systems with cold, infrared excesses, in order to investigate problems relating to the evolution of planetary systems, and to optimize the scientific results possible with ISO on such topics.
The effect of kenetic vs. thermodynamic acidity on the redox behavior of several 9-hydroxy- and 9-methoxyfluorenes

The electrochemical reductions of 9-methoxyfluorene (FlHOCH3), 9-methylfluorenol (Fl(CH3)OH) and 9-fluorenol (FlHOH) have been studied at a platinum electrode in DMF−0.1 M (n-Bu)4NClO4 over the temperature range −51°⩽T⩽22°C. The anion radicals of these compounds undergo heterolytic cleavage of the carbon—oxygen bond to give a fluorenyl radical (FlR, where R=H or CH3) and OR−. The subsequent redox behavior and follow-up solution reactions differ for each compound and depend upon the availability of a C9 and/or a hydroxylic proton. In the case of Fl(CH3)OH, the electrogenerated OH− abstracts a hydroxylic proton from unreacted starting material to give Fl(CH3)O−. Although this species is not oxidized, it is reduced at more negative potential to an unstable dianion radical that rapidly and indiscriminately abstracts proton. When a hydroxylic proton is not available, as in the case of FlHOCH3, the electrogenerated CH 3O− abstracts a proton from a component of the solvent-electrolyte system rather than from the C9 position. FlOCH3− is then formed slowly, but this is the result of C9 proton transfer from FlHOCH3 to the electrogenerated FlH−. Here, FlOCH3−, like FlH−, is oxidized irreversibly to its radical, but is not reduced in this solvent-electrolyte system. The OH− produced in the decomposition of FlHOH− abstracts only the hydroxylic proton from unreacted FlHOH. The cathodic wave for the reduction of FlHO− and the anodic wave for the oxidation of FlR− are kinetically controlled and result from the relatively slow abstraction of the thermodynamically more acidic C9 proton from FlHOH by FlHO− and FlH respectively.
Cigarette smoking is not a risk factor for systemic sclerosis

Objective To investigate the association of cigarette smoking with susceptibility to systemic sclerosis (SSc) in a large, well-defined patient population. Methods We conducted a review of 1,379 patients with SSc enrolled in the Scleroderma Family Registry and DNA Repository and/or the Genetics versus Environment in Scleroderma Outcome Study cohort. Smoking history was obtained from chart review or via telephone interview. Patients with SSc were subsequently categorized as never smokers or ever smokers. Patients with SSc for whom smoking data were available were matched 2:1 by age, sex, ethnicity, and state of residence to control subjects, using the Behavioral Risk Factor Surveillance System. Results The majority of patients were white (74.2%), with Hispanics and blacks representing 11.3% and 9.7%, respectively. Most patients had limited cutaneous involvement (54%). For our comparative analyses, 621 patients were matched with control subjects. There was no significant difference in age, sex, ethnicity, and SSc subtype between matched versus unmatched patients. The majority of patients had never smoked (57%), while 43% of patients were classified as ever smokers. The patients with SSc did not differ from control subjects in terms of their smoking behavior (odds ratio [OR] 1.020, 95% confidence interval [95% CI] 0.839–1.240, P = 0.842). Anti–topoisomerase I antibody–positive patients were more likely to be never smokers (OR 0.648, 95% CI 0.421–0.998, P = 0.049), whereas no such association was observed with anticentromere and anti–RNA polymerase III antibodies. Conclusion Unlike its role in rheumatoid arthritis, smoking does not confer a risk for development of SSc, although it may impact disease severity.
Delayed presentation and repair of isolated traumatic ventricular septal defect

The case report of an isolated ventricular septal defect due to blunt chest trauma presenting more than a month after the injury and its successful surgical management is presented.
YOUTH: decisions and challenges in designing an osteoporosis prevention intervention for teen girls.

Background. This paper describes decisions about the experimental design for the Youth, Osteoporosis, and Understanding Total Health Project (YOUTH), a trial designed to test the efficacy of a health plan-based lifestyle intervention for increasing bone mineral density among adolescent women 14 to 16 years of age. Methods. This randomized controlled trial recruited adolescent women who were at higher risk for developing osteoporosis (body mass index 16–23) from a large HMO in the Pacific Northwest. The intervention focused on improving diet (high calcium foods, fruits, and vegetables) and increasing physical activity (high impact and spinal motion). The intervention included both group and individual activities. The primary endpoint in the study was total bone mineral density as measured by dual-energy X-ray absorptiometry (DEXA). Results. Baseline data were collected on the trial cohort of 228 adolescent women and their families. This paper discusses how researchers met the following challenges in designing and implementing the trial: determining appropriate dietary and exercise targets to affect bone mineral density in adolescents; choosing suitable assessments; and developing an intervention well suited for implementation in a non-school (health plan) setting. We also discuss the rationale for the specific study population chosen (females, younger adolescents). Conclusions. The YOUTH project is one of very few preventive research interventions with adolescents conducted in a health plan setting. Many of the recruitment and intervention strategies used in this trial may be appropriate for adoption in other health plan-based prevention studies.
Preparation of polymeric stationary phase for use in inverse gas chromatography

Abstract The preparation of ground low‐density poly(ethylene) (LDPE), high‐density poly(ethylene) (HDPE), and poly(ethylene terephthalate) (PET) materials suitable for use by inverse gas chromatography (IGC) experiments is described. Materials prepared showed a smaller and more uniform particle size, 83–86 µm (200 mesh), than commercially available Chromosorb® W solid chromatography support. In addition, the BET surface area of polymeric materials, 0.367–0.559 m2/cm3, was much greater than the surface area of 150‐ to 212‐µm‐diameter glass beads. The use of polymeric materials with uniform particle sizes and defined surface areas have several advantages over polymer coated Chromosorb® W and glass beads in IGC experiments.
Development of the instantaneous unit hydrograph using stochastic differential equations

Recognizing that simple watershed conceptual models such as the Nash cascade ofn equal linear reservoirs continue to be reasonable means to approximate the Instantaneous Unit Hydrograph (IUH), it is natural to accept that random errors generated by climatological variability of data used in fitting an imprecise conceptual model will produce an IUH which is random itself. It is desirable to define the random properties of the IUH in a watershed in order to have a more realistic hydrologic application of this important function. Since in this case the IUH results from a series of differential equations where one or more of the uncertain parameters is treated in stochastic terms, then the statistical properties of the IUH are best described by the solution of the corresponding Stochastic Differential Equations (SDE's). This article attempts to present a methodology to derive the IUH in a small watershed by combining a classical conceptual model with the theory of SDE's. The procedure is illustrated with the application to the Middle Thames River, Ontario, Canada, and the model is verified by the comparison of the simulated statistical measures of the IUH with the corresponding observed ones with good agreement.
Effects of impairment-based individual and socially oriented group therapies on verb production in aphasia

Purpose: Two philosophies of intervention exist in aphasia rehabilitation: impairment-based approaches and socially oriented approaches. Both approaches have been shown to improve communication in persons with aphasia, but no studies have directly compared the effects of each approach or a combined approach on a targeted linguistic skill. This article explores the effects of individual and group therapies used both in isolation and in combination on verb production in aphasia.Methods: Twelve individuals with chronic aphasia were trained on transitive verbs under three conditions—individual, group and combined—over a 6-week interval. Treatment was counterbalanced across subject and training groups. A delayed-treatment, within-participant design was used. Verb probe data were collected at 10 points throughout the study. Language measures were taken at two intervals pre- and two intervals post-treatment. Functional, narrative and quality-of-life measures were taken once pre- and once post-treatment.Results: ...
Steam Foam Studies In The Presence Of Residual Oil

The lack of understanding regarding foam flow in porous media necessitates further research. This paper reports on going work at Stanford University aimed at increasing our understanding in the particular area of steam foams. The behavior of steam foam is investigated with a one dimensional (6 ft. {times} 2.15 in.) sandpack under residual oil conditions of approximately 12 percent. The strength of the in-situ generated foam, indicated by pressure drops, is significantly affected by injection procedure, slug size, and steam quality. The surfactant concentration effect is minor in the range studied. In the presence of residual oil the simultaneous injection of steam and surfactant fails to generate foam in the model even though the same procedure generates a strong foam in the absence of oil. Nevertheless when surfactant is injected as a slug ahead of the steam using a surfactant alternating (SAG) procedure, foam is generated. The suggested reason for the success of SAG is the increased phase mixing that results from steam continually having to reestablish a path through a slug of surfactant solution.
Fodorian semantics, pathologies, and “Block's Problem”

In two recent books, Jerry Fodor has developed a set of sufficient conditions for an object “X” to non-naturally and non-derivatively mean X. In an earlier paper we presented three reasons for thinking Fodor's theory to be inadequate. One of these problems we have dubbed the “Pathologies Problem”. In response to queries concerning the relationship between the Pathologies Problem and what Fodor calls “Block's Problem”, we argue that, while Block's Problem does not threatenFodor's view, the Pathologies Problem does.
Linear process calculations as convergence accelerators in flowsheet-sequenced programs

Linear process calculations were developed for use in conjunction with flow-sheet-sequenced calculations, as methods of convergence acceleration. Two such methods were compared with the successive substitution and Wegstein methods on relatively simple processes. “Linear Process Simulation,” which requires user-derived equations, produced the best results.
Distributed Space Situational Awareness (D-SSA) with a Satellite-assisted Collaborative Space Surveillance Network

Abstract This paper addresses the problem of tracking space-borne objects of interest (OoIs) with a satellite-assisted collaborative space surveillance network (SSN). It is formulated as a multiple moving-object tracking problem in a hybrid distributed wireless sensor network (WSN) made of both mobile and static nodes. The static nodes may be considered as ground-based sensors with fixed locations, while mobile sensor nodes can be satellites in space. At any given time, due to relative motion among nodes and OoI's, not all sensors are capable of observing a given target. The number of space OoI's (targets) of interest is several orders of magnitude larger than the number of nodes in the SSN, and each node can observe only a finite number of targets at a time. The challenge is to be able to schedule the nodes so that the best possible node-target assignments are made. A distributed approach is more desired in terms of scalability and robustness. However, for a distributed scheduling scheme to be efficient the distributed scheduling decisions need to be consistent across the network, which in turn requires the distributed local tracking estimates to be consistent across the network. As a result, the problem turns out to be a nonlinear consensus tracking problem on a time-varying graph with incomplete data and noisy communications links . We propose a distributed and collaborative framework in which each node in the network updates its tracking estimate of an object based on its own observations via an extended Kalman filter (EKF), followed by a consensus update stage in which nodes exchange their local estimates in order to arrive at a consensus on the distributed estimates leading to conflict-free node scheduling. Simulations of a two-dimensional hybrid SSN have been carried out in order to evaluate the performance of the proposed distributed tracking with consensus algorithm. The performance results show that the proposed algorithm indeed performs very well under conditions that can be expected in a realistic SSN, paving way for possible distributed scheduling.
Toward human-computer information retrieval

La necessite d'acceder a de vastes collections de donnees non structurees sur le Web requiert un nouveau type de systeme d'information, dans lequel un controle humain permanent s'exerce sur le processus de recherche. Cette approche hybride reunit les deux domaines de la recherche d'information d'une part et de l'interaction homme-machine d'autre part. Cette nouvelle conception de recherche d'information homme-machine, qui doit permettre aux utilisateurs d'explorer des bases d'information a grande echelle, repose notamment sur l'elargissement du controle et de l'implication humaine, et reflete l'interdependance des chercheurs d'information et des systemes et leur nature evolutive.
Effect of Baking on Amino Acids in Pizza Crust

Pizza crusts baked at 316°C for 4.5 min did not change their protein contents. But the high-temperature and short-time baking did reduce the lysine and to a lesser extent, tyrosine, cystine, and threonine in pizza crusts. The loss in total lysine content ranged from 7.1% for whole wheat pizza to 19.4% for a commercial pizza crust. The difference between the total and available lysine for each pizza crust was small, indicating that the nutritive loss of pizza crust should be attributed to the destruction of a portion of lysine in pizza crust.
Enzymically active subunits of neurospora invertase

Abstract 1. 1. Neurospora invertase (s- d -fructofuranoside fructohydrolase, EC 3.2.1.26) (s20,W = 10.3) can be dissociated to active subunits (s20,W = 5.2) by heat or by high salt concentrations at low or high pH. The subunits can reassociate to give the polymeric form. Both forms of the enzyme are active per se. 2. 2. Both forms of the enzyme are present in crude extracts of mycelia or washings from conidia. 3. 3. The polymeric form can be separated from the active subunit by gel electrophoresis or Sephadex G-200 filtration. 4. 4. When the polymeric form is subjected to conditions which cause partial dissociation, a transient form (s20,W = 9.8) is present. This probably represents the polymeric enzyme in a pre-clastic conformation. 5. 5. Some observations on the surface activity of invertase are briefly noted.
Magnetic field dependence of the microwave surface resistance of pure niobium

The microwave surface resistance of pure niobium has been measured in magnetic fields up toH c3 . The surface resistance in the mixed state state was found to depend strongly on the mean free path, in contrast to the earlier theory of Caroli and Maki but in agreement with the recent theoretical work of Cerdeira, Houghton, and Maki. Neglect in the theory of the surface solution for the order parameter limits the value of making comparisons with our results except in the orientation where the steady magnetic field is perpendicular to the surface. In this orientation we have found the slope of the curve of surface resistance plotted against flux density to be proportional to mean free path, as predicted by the recent theory. The theory has been developed only for absolute zero, and so in order to make comparisons we have extrapolated an empirical scaling procedure that reduces data at different temperatures to a single curve. Estimates of the constant of proportionality in the mean-free-path dependence are limited in accuracy by the present uncertainty in the values of κ 2 (T). Although both the earlier and recent theories purport to deal with the anisotropy of the surface resistance when the direction of the steady magnetic field is varied with respect to the wave vector of the electromagnetic field but is kept perpendicular to the microwave current, neither includes the large shielding effects produced by the vortex-free layer that can exist at the real surface and persist up toH c3 . Agreement with the mean free path dependence predicted by the recent theory could not be achieved by incorporating measurements aboveH c2 into a simple layer model to adjust the measured values of the surface resistance with the steady field parallel to the surface. However, the discrepancy between the predicted and measured anisotropies was reduced by this procedure. Other aspects of our experimental results that fall outside the range of validity of the recent theory are compared with general features established by earlier experimental and theoretical work on impure type II superconductors. In particular, the anisotropy of the surface resistance in fields just belowH c3 was found to be temperature independent, as predicted by Thompson and confirmed by Monceau and Waysand. The observed magnetic hysteresis effects in the mixed state are discussed in relation to the nascent vortex model and to the existence of an oxygen-rich surface layer.
UV curable polymers with organically modified clay as the nanoreinforcements

UV curable polymers are prevalent in microelectronic applications. Several advantages are associated with UV curing such as rapid cure, solvent free systems, application versatility, low energy requirements, and low temperature operation. To be used in electronics the films must posses the following attributes: high glass transition, barrier properties, low shrinkage, flexibility, and enhanced mechanical properties. The area of polymer-clay nanocomposites have been widely investigated by researchers and improved mechanical, thermal, and barrier properties were reported. Most researchers have attempted nanocomposite formation by melt mixing or in situ polymerization. Little is understood on UV curable nanocomposites. This paper seeks to examine nanoclay-containing polymers using organomodified montmorillonites in UV curable systems and the effects of such clay inclusions on the properties of UV cured films. By x-ray diffraction it appeared that intercalated structures were formed. In the case of an epoxy acrylate formulation an increase in glass transition temperature was observed for formulations containing clay.
Using agent technologies to correlate and compare anti-malware software

Malware is a fast growing threat that consists of software used to disrupt, or impact the confidentiality, availability or integrity of a user's computer experience. Antivirus software can help protect a user against these threats. There are numerous vendors users can choose from for their antivirus protection, each with their own set of virus definitions and various resources that are capable of recognizing new threats. However, there is no established system or process to measure and display data on the performance of antivirus vendors to new malware over an ongoing time period in real time. Such a mechanism would better inform end users of their security options in addition to informing organizations of prevalent threats occurring in networks. In this paper, we propose a cloud sourced malware reporting system that uses distributed agents to assess the performance of antivirus software based on malware signatures.
An efficient semi-implicit time accurate scheme for unsteady viscous flow on dynamic grids

This paper presents a semi-implicit method for efficient and high-order time-accurate computations for unsteady viscous hypersonic flows over fixed or moving bodies using Navier-Stokes equations. The equations are discretized in space using a second-order TVD scheme on moving structured grids. If explicit schemes are used to advance the equations in time, the small grid sizes in the wall-normal direction in the boundary layers imposed severe restrictions on the time steps. In the current method, the spatial discretization of the governing equations is separated into stiff terms involving derivatives along the wall-normal direction and nonstiff terms for the rest of the equations. The split equations are then advanced in time using second- and third-order semi-implicit Runge-Kutta schemes so that the nonstiff streamwise terms are treated by explicit Runge-Kutta methods and stiff wall-normal terms are simultaneously treated by implicit Runge-Kutta methods. The semi-implicit method leads to block pentagonal diagonal systems of implicit equations that can be solved efficiently. (Author)
Management of dialysis access-associated “steal” syndrome with DRIL procedure: challenges and clinical outcomes

PurposeThe Distal Revascularization Interval-Ligation (DRIL) procedure has demonstrated efficacy in the management of Dialysis Access-associated Steal Syndrome (DASS); however, this has not been wi...
Obstructive Sleep Apnea: Recognition and Management Considerations for the Aged Patient

Sleep-disordered breathing (SDB) problems are estimated to affect between 2% to 4% of Americans with an even higher incidence occurring as one ages. This article focuses on obstructive sleep apnea (OSA) as a risk to safety and a leading contributor to interrupted sleep and disease morbidity in the aged population. Obstructive sleep apnea is caused by interruption in upper airway airflow during sleep that leads to oxygen desaturations and disruptions in sleep continuity. The symptoms, diagnosis, and initial management of OSA are discussed that provide direction for the advanced practice nurse who encounters patients with this disease.
Yeast Protein Farnesyltransferase. pKas of Peptide Substrates Bound as Zinc Thiolates

Protein farnesyltransferase (PFTase) is a zinc metalloenzyme that catalyzes the posttranslational alkylation of the cysteine in C-terminal −Ca1a2X sequences by a 15-carbon farnesyl residue, where C is cysteine, a1 and a2 are normally aliphatic amino acids, and X is an amino acid that specifies selectivity for the farnesyl moiety. Formation of a Zn2+ thiolate in the PFTase·peptide complex was detected by the appearance of an absorbance at 236 nm (e = 15 000 M-1cm-1), which was dependent on the concentration of peptide, in a UV difference spectrum in a solution of PFTase and the peptide substrate RTRCVIA. We developed a fluorescence anisotropy binding assay to measure the dissociation constants as a function of pH for peptide analogues by appending a 2‘,7‘-difluorofluorescein to their N-terminus. The electron-withdrawing fluorine atoms allowed us to measure peptide binding down to pH 5.5 without having to correct for the changes in fluorescence intensity that accompany protonation of the fluorophore. Measur...
Impact of a statewide quality improvement initiative in improving the management of pediatric splenic injuries in washington state.

Background: Evidence suggests that 90% of children with traumatic spleen injuries can be successfully managed nonoperatively. In Washington State, significant interhospital variation in pediatric spleen management led to the development and implementation of a statewide quality improvement initiative in 2002. We evaluated pediatric splenic injury management before and after the implementation of a statewide quality improvement initiative. Methods: Retrospective cohort study using data from the Washington Trauma Registry for years 1999-2001 (preintervention) and 2003-2005 (postintervention). Children ages 0 to 14 years who were hospitalized with a traumatic (non-iatrogenic) splenic injury were included. Multivariable regression was used to control for patient and hospital characteristics. Results: Splenectomies were more common, occurring in 13.6% of children, in the preintervention period, compared with 7.8% in the postintervention period (p = 0.027). After adjusting for patient, injury, and hospital characteristics, children remained less likely to receive a splenectomy in the postintervention period than in the preintervention period (odds ratio 0.39, 95% confidence interval 0.19-0.82). Children cared for at pediatric trauma hospitals were less likely to receive splenectomy in both the preintervention and postintervention periods, compared with children treated at general trauma hospitals (p < 0.001). Splenectomy remained less common among children treated at pediatric-designated hospitals (odds ratio, 0.21; 95% confidence interval, 0.08-0.58) than among children treated in general trauma hospitals after controlling for intervention period. Conclusion: The statewide quality improvement initiative was associated with a reduction in the rate of splenectomy in both pediatric and general trauma hospitals. However, general trauma hospitals remained more likely to perform splenectomies than hospitals with pediatric trauma designation.
The effect of external electric currents on the heart; control of cardiac rhythm and induction and termination of cardiac arrhythmias.

Clinically, application of electric currents to the heart has been limited to defibrillation in the operating room when the heart is exposed. In this paper technics are described for the external application of stimulating and countershock currents. They have been used successfully in man to terminate ventricular standstill from any cause and to stop ventricular tachycardia or fibrillation. For experimental purposes an additional technic has been developed for producing various cardiac arrhythmias by rapid external stimulation of the heart.
Quantitative characterization of rubbery ethylene-propylene copolymers used in some commercial high impact nylons

An analytical method has been developed for the rapid quantitative characterization of maleinated EPR and EPDM rubbers in representative commercially available (DuPont, I.C.I.) high-impact nylons. The DuPont product is a nylon graft containing ∼ 20% (wt) maleinated EPDM whereas the I.C.I. product contains ∼20% (wt) maleinated EPR. The maleic anhydride residue attached to the rubber has been determined quantitatively. The rubber in both samples is partially crosslinked. The crosslink-density of the rubber in the I.C.I. product is much higher than that in the DuPont product. The rubbery phase in the DuPont and I.C.I. products contains a crystalline component.
Impact of Gender on Neointimal Hyperplasia Following Coronary Artery Stenting

Whether gender affects long-term outcomes after bare metal stent implantation remains controversial. The aim of this study was to examine the impact of gender on neointimal hyperplasia in a large cohort of patients after stent implantation using 3-dimensional intravascular ultrasound. Lumen and stent areas were manually traced at 0.5-mm intervals throughout the stented segment. Using Simpson's method, lumen, stent, and neointimal (stent - lumen) volumes were calculated and standardized by stent length. Women were older, presented more often with hyperlipidemia or hypertension, and had smaller reference vessel diameter and mean stent area, compared with men. Although neointimal hyperplasia and neointimal thickness in women were similar to that in men, the percentage of neointimal hyperplasia (neointimal area divided by stent area) was higher in women due to the smaller stent area. After adjusting for stent area, the percentage of neointimal hyperplasia did not differ by gender. In conclusion, the results of this study indicate that neointimal hyperplasia after bare metal stent implantation in women is similar to that seen in men. Despite the similarity in outcome, there are several gender-specific differences in baseline characteristics.
Health-related quality of life in a national sample of caregivers: Findings from the behavioral risk factor surveillance system

Purpose Recent national public health agendas, such as Healthy People 2010, call for improved public health surveillance and health promotion programs for people with disabilities and their caregivers. The goal of this study was to understand the public health impact of caregiving on health-related quality of life (HRQoL) using population-level data. Design & Methods A cross-sectional study design was used. 184,450 adults surveyed during the 2000 national Behavioral Risk Factor Surveillance System survey formed the sample. Binary logistic regression models ascertained differences between caregivers and non-caregivers in reporting reduced (“fair” or “poor”) health. Ordinary least squares regression (OLS) and multinomial logistic regression models examined the influence of caregiving status on HRQoL, measured as categories of healthy days reported in the last 30 days and the number of days reported as physical and mental health not good in the last 30 days. Results Sixteen percent (16%) of the survey respondents were caregivers. There was an interaction effect between caregiving status and age of the caregiver. In the fully adjusted models, caregivers <55 years old had a 35% increased risk of having fair or poor health (odds ratio [OR] = 1.35, 95% confidence interval [CI] 1.28, 1.43) as compared to non-caregivers in that age group, while caregivers 55 years and older had a 3% decreased risk in having fair or poor health (OR = 0.97, 95% confidence interval [CI] 0.92, 1.03) compared to non-caregivers of the same age. In the adjusted models that examined the association of caregiving and healthy days, younger caregivers similarly showed larger deficits in both mental and physical HRQoL compared to older caregivers. For example combining mental and physical days, caregivers <55 had 1.44 fewer healthy days (β = −1.44, standard error (SE) = 0.07), while caregivers 55+ had 0.55 fewer days *β = −0.55, standard error (SE) = 0.13 (compared to non-caregivers in their respective age groups). Implications With increasing population age and the projected increase in caregivers, it is important that we understand the social and public health burden of caregiving and begin to identify interventions to sustain the HRQoL of caregivers. We found that caregivers have a slight to modest decline in HRQoL compared to non-caregivers, and that caregiving affects the HRQoL of younger adults more than older adults. Further research at the population level as to the type and level of burden of caregiving is needed.
Loss of laterality in chronic cocaine users: an fMRI investigation of sensorimotor control

Movement disturbances are often overlooked consequences of chronic cocaine abuse. The purpose of this study was to systematically investigate sensorimotor performance in chronic cocaine users and characterize changes in brain activity among movement-related regions of interest (ROIs) in these users. Functional magnetic resonance imaging data were collected from 14 chronic cocaine users and 15 age- and gender-matched controls. All participants performed a sequential finger-tapping task with their dominant, right hand interleaved with blocks of rest. For each participant, percent signal change from rest was calculated for seven movement-related ROIs in both the left and right hemisphere. Cocaine users had significantly longer reaction times and higher error rates than controls. Whereas the controls used a left-sided network of motor-related brain areas to perform the task, cocaine users activated a less lateralized pattern of brain activity. Users had significantly more activity in the ipsilateral (right) motor and premotor cortical areas, anterior cingulate cortex and the putamen than controls. These data demonstrate that, in addition to the cognitive and affective consequences of chronic cocaine abuse, there are also pronounced alterations in sensorimotor control in these individuals, which are associated with functional alterations throughout movement-related neural networks.
Paradoxical Effect of Mitochondrial Respiratory Chain Impairment on Insulin Signaling and Glucose Transport in Adipose Cells

Adipocyte function is crucial for the control of whole body energy homeostasis. Pathway analysis of differentiating 3T3-L1 adipocytes reveals that major metabolic pathways induced during differentiation involve mitochondrial function. However, it is not clear why differentiated white adipocytes require enhanced respiratory chain activity relative to pre-adipocytes. To address this question, we used small interference RNA to interfere with the induction of the transcription factor Tfam, which is highly induced between days 2 and 4 of differentiation and is crucial for replication of mitochondrial DNA. Interference with Tfam resulted in cells with decreased respiratory chain capacity, reflected by decreased basal oxygen consumption, and decreased mitochondrial ATP synthesis, but no difference in many other adipocyte functions or expression levels of adipose-specific genes. However, insulin-stimulated GLUT4 translocation to the cell surface and subsequent glucose transport are impaired in Tfam knockdown cells. Paradoxically, insulin-stimulated Akt phosphorylation is significantly enhanced in these cells. These studies reveal independent links between mitochondrial function, insulin signaling, and glucose transport, in which impaired respiratory chain activity enhances insulin signaling to Akt phosphorylation, but impairs GLUT4 translocation. These results indicate that mitochondrial respiratory chain dysfunction in adipocytes can cause impaired insulin responsiveness of GLUT4 translocation by a mechanism downstream of the Akt protein kinase.
CORRECTION OF THE DRIFT MOBILITY MEASUREMENTS IN GAAS MESFETS

Abstract Drift mobility and electron concentration values in GaAs MESFETs obtained by capacitance-conductance measurements are corrected by means of a self-consistent iterative procedure. The final results are compared with the experimental Hall mobility data for the same wafer. It is found that the agreement is good for temperatures T > 175 K.
Atrial septostomy as a bridge to lung transplantation in patients with severe pulmonary hypertension.

Abstract Long waiting times for lung transplantation have limited the survival of patients with advanced pulmonary hypertension. Atrial septostomy has been used in this group of patients in an attempt to prolong survival. We evaluated the results of atrial septostomy in 12 patients using the static graded balloon dilation technique. Between December 1990 and May 1998, 10 women and 2 men (ages 13 to 56 years, mean 37 years) underwent atrial septostomy. Nine patients had primary and 3 patients had secondary pulmonary hypertension. Five patients deteriorated despite long-term intravenous prostacyclin infusions. The atrial septum was crossed with a Brockenbrough needle, followed by an 0.035-J exchange wire and progressively larger catheter balloons for atrial septal dilation, until systemic oxygen saturation decreased 5% to 10%. An atrial septal defect was successfully created in each patient. The mean right atrial pressure decreased from 23 to 18 mm Hg and the mean systemic oxygen saturation decreased from 93% to 85%. The mean cardiac index increased from 1.7 to 2.1 L/min/m 2 and the mean systemic oxygen transport increased from 268 to 317 ml/min/m 2 . Complications occurred in 3 patients: transient hypotension during transesophageal echocardiography, a femoral pseudoaneurysm, and a femoral arteriovenous fistula. After septostomy, 6 patients had clinical improvement (resolution of ascites, edema, and no further episodes of syncope); 5 of these 6 patients underwent lung transplantation a mean of 6.1 months after septostomy. Six patients did not have clinical improvement after septostomy. Atrial septostomy improves the hemodynamic status and may be useful as a bridge to lung transplantation in selected patients with pulmonary hypertension.
The role of tyrosinase in the inactivation of house fly microsomal mixed-function oxidases☆

Abstract The low mixed-function oxidase activity of house fly microsomes has been associated with low cytochrome P -450 content and NADPH-cytochrome c reductase activity. The microsomal cytochrome P -450 content and NADPH-cytochrome c reductase activity could be decreased by the addition of catechol and increased by the addition of cyanide to the homogenates. Similar results were obtained with rat liver microsomes treated with tyrosinase and catechol. During the inactivation of rat liver microsomal enzymes by tyrosinase and catechol, crosslinking of microsomal proteins occurred. These results suggest that the instability of house fly microsomal mixed-function oxidase may be due in part to the action of contaminating tyrosinase on endogenous substrates.
Background-free absorption spectroscopy using delayed balanced detection

A new, simple, background-free absorption spectroscopy technique is used to measure the absorption spectrum of acetylene from 1539.7 to 1542.4 nm at 10-kHz repetition rate. Whereas more traditional background-free methods such as wavelength-modulation spectroscopy (WMS) or frequency-modulation spectroscopy (FMS) rely on modulating the injection current of the light source as well as lock-in detection, this new approach directly yields a difference signal through delayed balanced detection that is equivalent to the 1f signal in WMS. Residual amplitude-modulation (RAM), which can be problematic in WMS and FMS, is not present in this method because no dithering of the injection current is required. In addition, virtually any modulation depth can be realized simply by adjusting an optical delay line.
Cardiac Magnetic Resonance Versus Routine Cardiac Catheterization Before Bidirectional Glenn Anastomosis in Infants With Functional Single Ventricle A Prospective Randomized Trial

Background— Routine preoperative catheterization is standard practice in patients with single-ventricle physiology before bidirectional Glenn anastomosis. Because catheterization is invasive and ex...
Applications of the second virial coefficient: protein crystallization and solubility

This article begins by highlighting some of the ground-based studies emanating from NASA's Microgravity Protein Crystal Growth (PCG) program. This is followed by a more detailed discussion of the history of and the progress made in one of the NASA-funded PCG investigations involving the use of measured second virial coefficients (B values) as a diagnostic indicator of solution conditions conducive to protein crystallization. A second application of measured B values involves the determination of solution conditions that improve or maximize the solubility of aqueous and membrane proteins. These two important applications have led to several technological improvements that simplify the experimental expertise required, enable the measurement of membrane proteins and improve the diagnostic capability and measurement throughput.
A statistical image reconstruction method to reduce small angle scattering induced streaking artifacts in differentialphase contrast CT

Statistical iterative reconstruction methods have come to the forefront of CT research in recent years, as they have the ability to incorporate the statistical fluctuations in CT measurements into the image reconstruction process. While statistical iterative reconstruction methods have been found to be beneficial in CT imaging, they have not been extensively investigated or applied in other new and promising CT imaging techniques, such as x-ray differential phase contrast computed tomography (DPC-CT). The purpose of this study is to investigate and apply statistical image reconstruction to DPC-CT to reduce streaking artifacts caused by strong small-angle scattering objects.
The Zhouyi (Book of Changes) as an Open Classic: A Semiotic Analysis of Its System of Representation

The Zhouyi is the first of the Chinese classics and has, since medieval times, fascinated scholars from different parts of the world, who have produced numerous studies and expressed a dazzling array of views on its nature. It is argued that the Zhouyi has retained its exalted status and enduring appeal largely because it is an open book amenable to all kinds of appropriations and manipulations, and its openness comes from its being a semiotic system whose principle of composition warrants unlimited interpretations. Through a semiotic-cum-philosophical inquiry, it is shown that the Zhouyi is first and foremost a system of representation, and because of its unique structure and principle of signification it forms an open hermeneutic space with infinite possibilities of interpretation.