cssi/SciSciGPT-SciSciNet huggingface dataset:
Coupled Oscillations in Food Webs: Balancing Competition and Mutualism in Simple Ecological Models

As in other oscillating systems, oscillations of consumer resource pairs in ecological systems may be coupled such that complex behavior results. The form of that coupling may determine the nature and extent of this behavior. Two biologically significant forms of coupling are here investigated: first, where consumers consume each other's resources (CR coupling, representing competition between the two consumers), and second, where the resources are in competition with one another (RR coupling, potentially representing indirect mutualism between the two consumers). Interestingly, CR coupling leads to in-phase synchrony of the oscillations, whereas RR coupling leads to antiphase synchrony. With either form of coupling, if the coupling remains weak, synchronous behavior is generated in the two systems. At strong levels of coupling, when the two forms act simultaneously, a balance between competition and mutualism is generated, which is manifest differently at different levels of resource coupling.
The development of an understanding of balance and the effect of training via stop-action video

Children's rule-governed, scientific reasoning in relation to the physical principles involved in balance has been studied by many, for example, Inhelder and Piaget (1958), Karmiloff-Smith and Inhelder (1974), as well as Siegler (1978). Although Siegler criticized the Genevan research on both methodological and conceptual grounds, his work can be criticized for being narrow in scope thus making his data a result of his task and design, rather than a true representation of the rules children employ naturally as they develop an understanding of balance. The work described herein is an attempt to integrate the methodologies of the Piagetian School and Siegler by making use of current video technology to naturalistically assess children's rule-governed behaviors but to also empirically validate them. The first part of this study (N=128, ages 4-9 years) used video to microanalytically assess the strategies children used as they attempted to balance a set of symmetrical, asymmetrical, and weighted blocks on a fulcrum. After validating on ordinal progression of strategies, the study used stop-action video feedback, in a predict-consequence paradigm, to focus reflection on (a) the action of the block, (b) the placement of the block, and (c) the episode in general. A two-way interaction between entering level and type of video feedback was significant. The results are interpreted in terms of Piaget's theory of equilibration suggesting that reflection and cognitive conflict can improve understanding if the child assimilates the feedback to the confirmation or refutation of an initial assimilatory scheme regarding balance.
Intracellular Transport: Force Controls Motor Switching at Filament Junctions

How does cellular traffic switch direction on microtubules, or switch back and forth between microtubule- and actin-based tracks? A pair of recent studies mimics the layout of motors and tracks within the cell to provide intriguing answers to these questions.
Crumbs from the Publishers' Golden Tables: The plight of the Chicago newsboy

(2000). Crumbs from the Publishers' Golden Tables: The plight of the Chicago newsboy. Media History: Vol. 6, No. 1, pp. 45-57.
The Storage, Rejuvenation, and Restorage of Human Red Cells for Periods up to 56 Days.

Abstract : Human red cells may be stored at 4 C for periods up to 56 days and then successfully rejuvenated by the Valeri PIGPA procedure. The rejuvenated red cells have near normal levels of ATP and 2,3-DPG and retain these elevated levels for at least 4 days following rejuvenation. This greatly increases the usefulness of outdated stored red cells, both in terms of reclaiming the red cells for freezing or in rejuvenation to extend the outdating period of 4 C stored blood to 42 or 56 days. (Author)
Use of Diuretics in the Treatment of Heart Failure in the Elderly

Diuretics are tools of considerable therapeutic importance. First, they effectively reduce blood pressure, while at the same time decreasing the morbidity and mortality associated with hypertension. Diuretics are currently recommended as first-line therapy for the treatment of hypertension. In addition, they remain an important component of heart failure therapy, in that they improve the symptoms of congestion, which typify the more advanced stages of heart failure. This article reviews the mode of action of the various diuretic classes and the physiologic adaptations that follow; sets up the basis for their use in the treatment of volume-retaining states, particularly as applies to the elderly; and reviews diuretic-related side effects that are normally encountered.
New derivation of a theory of quantum crystals

A new variational cluster-expansion derivation of Guyer's theory of the ground state of a quantum crystal is presented. The results are identical with his in the two-body correlation approximation except that the variational approach provides a justification of the minimization technique used to choose the unperturbed Hamiltonian. The treatments differ in the higher correlation terms because of the use of a Jastrow trial function.
A comparison of broadband source spectra, seismic energies, and stress drops of the 1989 Loma Prieta and 1988 Armenian earthquakes

Broadband source spectra of the 1989 Loma Prieta (MW = 6.9) and 1988 Armenian (MW = 6.7) earthquakes are computed at periods from 1 to 50 sec using digitally-recorded teleseismic P body waves. The effects of attenuation, geometrical spreading, and radiation pattern are removed from the spectra of individual stations, which are then averaged. The source spectra of the Loma Prieta and Armenian earthquakes are higher for their seismic moments than the spectra of 11 intraplate earthquakes studied by Zhuo and Kanamori [1987], which in turn are 2 to 4 times larger than average spectra of interplate subduction zone earthquakes. The seismically radiated energy can be computed from the source spectrum using Haskell's [1964] formulation assuming a point source with no directivity. An Orowan stress drop can be obtained from the seismic energy and moment. The Orowan stress drops for the Loma Prieta and Armenian earthquakes are both about 20 bars, significantly higher than Orowan stress drops of recent large interplate earthquakes. There is a positive correlation between the Orowan stress drops and the estimated repeat times, consistent with the notion that mechanical fault strength increases with increasing interseismic period.
Involvement of p38 MAPK in the up-regulation of tissue factor on endothelial cells by antiphospholipid antibodies.

Objective To study the intracellular mechanism involved in the up-regulation of tissue factor (TF) on endothelial cells (ECs) by antiphospholipid antibodies (aPL), we examined the effects of aPL on the transcription, expression, and function of TF, the expression of interleukin-6 (IL-6) and IL-8, the induction of inducible nitric oxide synthase (iNOS), and the phosphorylation of p38 MAPK on human umbilical vein ECs (HUVECs). Methods Cultured HUVECs were treated with IgG aPL (from patients with antiphospholipid syndrome [APS]) or with control IgG (from normal human serum). Phorbol myristate acetate (PMA) and bacterial lipopolysaccharide (LPS) were used as positive controls. TF expression was determined on the surface of HUVECs using an enzyme-linked immunosorbent assay (ELISA). TF activity was determined with the use of a chromogenic assay in cell lysates, and TF messenger RNA (mRNA) was determined by real-time quantitative polymerase chain reaction. Phosphorylation of p38 MAPK and induction of iNOS were determined by Western blotting, and levels of IL-6 and IL-8 were determined by ELISA. Results PMA, LPS, and aPL significantly increased the expression of TF compared with controls. This up-regulation was significantly inhibited by SB203580 (a specific inhibitor of p38 MAPK) and by MG132 (a specific inhibitor of NF-κB). TF activity was significantly increased by treatment with IgG aPL and this effect was also inhibited by SB203580. Incubation of HUVECs with aPL increased TF mRNA 2–15-fold; these effects were abrogated by SB203580. IgG aPL induced significant phosphorylation of p38 MAPK and produced iNOS on HUVECs in a time-dependent manner. Treatment with IgG aPL also induced increased expression of IL-6 and IL-8 on HUVECs. Conclusion Our data show that aPL induces significant increases in TF transcription, function, and expression, in IL-6 and IL-8 up-regulation, and in iNOS expression on HUVECs and that these processes involve phosphorylation of p38 MAPK and activation of NF-κB. Understanding intracellular events in aPL-mediated EC activation may help in designing new targeted therapies for thrombosis in APS.
Can We Mass Produce a College/School Partnership for Professional Practice?

(1992). Can We Mass Produce a College/School Partnership for Professional Practice? Action in Teacher Education: Vol. 14, At the Crossroads: Visionary Leadership for Teacher Education, pp. 57-61.
A central binocular mechanism affects chromatic adaptation

Abstract Two experiments explored the role of central binocular mechanisms in color preception. The first experiment examined the effect of adapting to simultaneous, binocularly fused fields; Each eye adapted to a slowly flickering (0.5 Hz) long-wavelength light. The two eyes were adapted either inphase (both eyes stimulated at the same moment) or out-of-phase (only one eye stimulated at any given moment). Both adapting procedures shifted equilibrium yellow toward longer wavelengths, but a significantly greater shift was found when adapting light stimulated both eyes simultaneously. This reveals that a central binocular mechanism affects chromatic adaptation. The second experiment tested whether the binocular mechanism could shift equilibrium yellow measurements made with both eyes (identical, binocularly fused fields presented to each eye) outside of the range of measurements established by left-eye monocular viewing and right-eye monocular viewing. Differences were found between monocular left-eye and monocular right-eye color appearance under conditions of moderate chromatic adaptation, but binocularly fused measurements fell within the range established by the monocular results. This is consistent with the view that central mechanisms serve to keep the two eyes in balance, rather than systematically alter color appearance from colors perceived under monocular viewing.
USING PAST DATA TO ENHANCE SMALL-SAMPLE DIF ESTIMATION: A BAYESIAN APPROACH

The application of the Mantel-Haenszel test statistic (and other popular DIF-detection methods) to determine DIF requires large samples, but test administrators often need to detect DIF with small samples. There is no universally agreed upon statistical approach for performing DIF analysis with small samples; hence there is substantial scope of further work on the problem. One advantage of a Bayesian approach over a frequentist approach is that the former can incorporate, in the form of a prior distribution, existing information on the inference problem at hand; a prior distribution often leads to improved estimation, especially for small samples. Further, for any operational test, a huge volume of past data is available, and for any item appearing in a present test, there is a high chance that a number of similar items have appeared on past operational administrations of the test. Therefore, ideally, it will be possible to use that past information as a prior distribution in a Bayesian DIF analysis. This paper discusses how to perform such an analysis. The suggested Bayesian DIF analysis method is shown to be an improvement over the existing methods in a realistic simulation study.
Fabrication, characterization, and dynamic behavior of polyester/TiO2 nanocomposites

Abstract Unsaturated polyester resin specimens embedded with small loadings of 36 nm average diameter TiO 2 particles were fabricated using a direct ultrasonification method to study the effects of nanosized particles on nanocomposite bulk mechanical properties. The ultrasonification method employed produced nanocomposites with excellent particle dispersion as verified by transmission electron microscopy (TEM). Quasi-static fracture toughness, tension, and compression testing was carried out. The presence of the particles had the greatest effect on fracture toughness; negligible influence was observed in the remaining quasi-static properties. Scanning electron microscopy (SEM) of fracture surfaces was carried out to identify toughening mechanisms. The inadequacy of the bond between the filler and the matrix and the presence of minor particle agglomerations in specimens containing higher volume fractions of particles were believed to be responsible for a consistent decrease in property values beyond a volume fraction of 1 vol.%. Dynamic fracture toughness testing was carried out, and an increase in dynamic fracture toughness relative to quasi-static fracture toughness was observed. High strain rate testing conducted using a split Hopkinson pressure bar (SHPB) apparatus revealed a moderate stiffening effect with increasing particle volume fraction, although no marked effect was observed on the ultimate strength.
Accuracy in Predicting Situational Variations in Help-Seekers' Responses:

Over 300 subjects at four different age levels predicted situational variations in two different self-reported responses of persons asking for help. Accuracy at this task was substantially better than chance. Subjects were more accurate in predicting the importance to askers of getting help than their feelings about asking for help. Predictions of importance were relatively more accurate in same-sex giver-asker dyads, while predictions of feelings were relatively more accurate in opposite-sex dyads. Females were more accurate predictors than males, and they were more accurately judged than males.
Anomalous cold in the Pangaean tropics: COMMENT: COMMENT

[Soreghan et al. (2008)][1] present the hypothesis that glaciation existed to near sea level in the tropical region of Pangaea in late Paleozoic time. Their most important evidence for this comes from Unaweep Canyon, a wind gap that crosses the Uncompahgre Plateau, (Colorado, United States). The
ORAL USE OF PREGNENINONOL IN FUNCTIONAL MENO-METRORRHAGIA

INHOFFEN AND HOHLWEG (1) prepared recently a derivative of estradiol, which I(NHOFFEN)was identified(AND HOHLWEG)as pregnen-in-on-3-ol-17. These workers reported that, when this compound was injected into immature mice, previously treated with estrogens, it was approximately one-third as effective in producing progestational changes as was synthetic progesterone, similarly administered. It was observed, however, that when pregneninonol was given by mouth to similar animals, it was approximately 15 times as potent as progesterone given orally. A well developed progestational endometrium was produced in immature mice following the oral administration of 4 mg. of pregneninonol, whereas 60 mg. of progesterone by mouth were required for a similar response. One of us (E.C.H., 2,) reported previously that pregneninonol and certain estrogens had been given orally in the treatment of mencmetrorrhagia and that no untoward reactions or evidence of toxicity had followed. Apparent beneficial effects upon the character...
Technical and management notes: Sources of papers published in IEEE transactions on engineering management: A case study

The mix of academic and practitioner authors in the IEEE Transactions on Engineering Management is apparently an item of recurring interest. Repeatedly, the question is asked: “Why can't we get more papers from practitioners?” The question remains unanswered in spite of unvalidated statements to the contrary.
Characterization of surface layers produced by ion implantation of nitrogen in bulk aluminium

Abstract Surface layers of overall extent less than 400 nm have been generated by ion implantation of nitrogen as N + or N + 2 at energies of 50 and 100 keV into high-purity aluminum sheet at ambient temperature. These layers have been characterized by Auger electron spectroscopy with concurrent ion etching, scanning electron microscopy of the surface, and transmission electron microscopy in plan and cross-section geometries. Rutherford backscattering spectrometry, particle-induced X-ray emission and nuclear reaction analysis were used to assess cumulative changes in surface composition. The surface composition was found to be determined by the combined effects of sputtering, ablation, and recoil implantation of both existing surface oxides and reactive species incorporated into the surface during the process of ion implantation. Regions of AlN could be identified in the subsurface at an ion dose of 1 × 10 17 N + 2 cm -2 at 50 keV. The apparently non-contiguous regions of AlN formed semi-coherently with parent aluminum grains. The reaction layer, containing AlN, residual aluminum metal and oxygen, was found to grow toward the original passivated metal surface with increasing ion dose.
Effects of internal browning and watercore on low field (5.4 MHz) proton magnetic resonance measurements of T2 values of whole apples

Abstract Apples with internal browning and/or watercore along with unaffected apples were tested using a low frequency (5.4 MHz) proton magnetic resonance ( 1 H MR) sensor. A three-term exponential model was fit to the spin–spin relaxation ( T 2 ) curves obtained from individual apples. The contributions from terms of the model associated with extracellular spaces, a (ca. 16 ms) and the cytoplasm, b (ca. 300 ms) increased with the severity of internal browning ( r 2 = 0.7, 0.9, respectively). Conversely, the contribution of the term associated with water in the vacuoles, c (ca. 1260 ms) decreased as the severity of internal browning increased ( r 2 = 0.9). The changes in the model parameters were different for apples having only internal browning compared to apples with both moderate watercore and slight or no internal browning and the differences were statistically significant ( P r 2 ≅ 0.7). The results of this study suggest that when a three-term exponential model is fit to the T 2 relaxation curve from a low field 1 H MR sensor, the changes in the parameters may give an indication of the presence and severity of internal browning as well as the presence of watercore in the apple.
Formation of 2-cyanomethylenecyclohexyl acetate by incubation of acetate with slices of jojoba cotyledons

Abstract E-2-cyanomethylene-4,5-dimethoxy-3-hydroxycyclohexyl acetate was isolated and characterized from the incubation of either developing or germinating joj
Effective Cu surface pre-treatment for high-reliable 22nm-node Cu dual damascene interconnects with high plasma resistant ultra low-k dielectric (k=2.2)

Effects of Cu surface treatment (NH"3 plasma irradiation) before the cap dielectric deposition on low-k surface damage and Cu surface cleaning were systematically investigated. From the blanket film surface damage evaluations of porous low-k film with high carbon content and the oxygen removal on blanket Cu film after chemical mechanical polishing (CMP), the optimized NH"3 plasma condition such as high RF power and high pressure exhibited the high efficiency for oxygen removal from the Cu surface without increasing the k-value of low-k film. The low-k/Cu interconnect (line/space=40/40nm) for 22nm-node with the high plasma resistant low-k film and the optimized Cu surface treatment showed longer electro-migration lifetime without large degradation of RC performance.
Contractions of graphs

The contractibility number (also known as the Hadwiger number) of a connected graph G, Z(G), is defined as the maximum order of a connected graph onto which G is contractible. An elementary proof is given of a theorem of Ore about this invariant. Also, the extremal problem of finding the maximum Z(G) over all graphs G of a given order and regularity degree is solved.
90°-Domain reversal in Pb(Zrx, Ti1-x)O3 ceramics

Abstract In this study, a simple and direct method has been proposed, which can to be used for quantitatively distinguishing the mechanisms of domain reorientation processes in polycrystalline materials. By using this method, the 90° -domain reorientation in the Pb(ZrxTi1-x)O3 ceramic under the electric field was examined through the X-ray diffraction analysis. It was found that the polarization switching in the PZT ceramic with the composition near the morphotropic phase boundary is predominantly controlled by the two successive 90° domain processes rather than only the 180° domain reversal process. Experimental results also indicate that the coercive field of ferroelectric ceramics is related to the cooperative deformation associated with each grain. This cooperative deformation arises from 90°-domain reversal process.
Experience with the hansen robotic system for atrial fibrillation ablation--lessons learned and techniques modified: Hansen in the real world.

Introduction: The Hansen robotic system has only recently been used in the United States for catheter ablation procedures in humans. Atrial fibrillation (AF) ablation may be performed utilizing this system. We report our management of complications with early experience of this system. Methods and Results: All 71 patients in whom the system was utilized were included. In all patients, a 2-operator technique was to be employed; one operator manipulates the ablation catheter via the robot and the other manipulates the circular mapping and intracardiac echocardiogram catheters. There was no procedure-related mortality. All vascular complications occurred in the first 25 procedures performed. There were 6 intraoperative procedural-related complications. These included significant vascular complications (n = 4), one of whom required iliac vein stenting, and 2 cardiac tamponade (one related to a pop-phenomenon)—successfully treated by pericardiocentesis. Early complications (n = 3) were 1 tamponade several hours post-procedure, 1 vascular complication, and 1 pericarditis. Late complications included 5 patients with severe pulmonary vein stenosis (all in first 27 patients) and 1 patient with gastroparesis. All complications were successfully managed without persistent morbidity and occurred earlier in our experience. This led to specific alterations in our vascular access and ablation techniques. These include the use of a longer 14 Fr sheath, through which the robotic sheath is more safely advanced. The choice of ablation catheter and titration of power, particularly when the catheter has a perpendicular orientation to the atrial wall, is also important. Conclusions: The suggested modifications may make the system easier to use with the potential to reduce complications.
Ure2p Function Is Enhanced by Its Prion Domain in Saccharomyces cerevisiae

The Ure2 protein of Saccharomyces cerevisiae can become a prion (infectious protein). At very low frequencies Ure2p forms an insoluble, infectious amyloid known as [URE3], which is efficiently transmitted to progeny cells or mating partners that consequently lose the normal Ure2p nitrogen regulatory function. The [URE3] prion causes yeast cells to grow slowly, has never been identified in the wild, and confers no obvious phenotypic advantage. An N-terminal asparagine-rich domain determines Ure2p prion-forming ability. Since ure2Δ strains are complemented by plasmids that overexpress truncated forms of Ure2p lacking the prion domain, the existence of the [URE3] prion and the evolutionary conservation of an N-terminal extension have remained mysteries. We find that Ure2p function is actually compromised in vivo by truncation of the prion domain. Moreover, Ure2p stability is diminished without the full-length prion domain. Mca1p, like Ure2p, has an N-terminal Q/N-rich domain whose deletion reduces its steady-state levels. Finally, we demonstrate that the prion domain may affect the interaction of Ure2p with other components of the nitrogen regulation system, specifically the negative regulator of nitrogen catabolic genes, Gzf3p.
Electricity Deregulation: Kilowatts for Nothing and Your BTUs for Free

Historically, the electric power industry has been viewed as a natural monopoly that could best be managed through governmental regulation. This article traces the evolution of deregulation in the electric power industry and the intellectual, political, and economic trends and forces that modified this traditional view. It concludes that, despite policy change, retail competition of electricity remains a difficult concept to implement in part because electricity is basically a commodity. Customers must be provided with sufficient incentives to shop between electricity providers and there must be supply incentives for more efficient production. Competition also requires technological advances such as affordable “smart” meters that make it possible for customers to specify tradeoffs between price and consumption, even to the extent of programming apliances to turn on or off in response to price signals. Mature wholesale markets and open access to transmission and distribution are also neede.
Eco-epidemiology as anti-terrorism

Eco-epidemiology is a promising model for cross-disciplinary anti-terrorism. Derived from epidemiology's dominance of agents to illness and injury, the eco-epidemiological paradigm considers natural systems that generate causal pathways to disease and dynamic morbidity. Within this model is a hierarchy of systems interconnecting at biological, human, and social levels. Eco-epidemiology capitalizes on interacting components within and between system levels to identify contact patterns and apply mechanisms of control. Considering the complex and paradoxical nature of the threat-fear dynamic, a systematic, ecological approach would be more adaptive to terrorism's changing rules of engagement. To counter terrorism and nullify threat-fear, eco-epidemiology must be shared by public health researchers with threat assessment and harm reduction disciplines.
Nasal secretory response to allergen provocation

Summary Nasal provocation with ragweed pollen extract was performed on ragweed-sensitive and non-atopic subjects. Nasal lavage fluids were collected 15 min after saline and allergen challenges, and assayed for total protein, albumin, potassium, lysozyme activity and peroxidase activity. There was no statistically significant increase in any of these lavage fluid constituents in non-atopic subjects after allergen provocation, compared with after saline provocation. The lavage fluids of ragweed-sensitive subjects had significant rises in each of the constituents following allergen provocation. This method provides a simple mechanism for quantitating the nasal secretory response to allergen provocation.
Modeling of Nonrecursive Structural Equation Models With Categorical Indicators

Nonrecursive structural equation models generally take the form of feedback loops, involving 2 latent variables that are connected by 2 unidirectional paths, 1 starting with each variable and terminating in the other variable. Nonrecursive models belong to a larger class of path models that require the use of instrumental variables (IVs) to achieve model identification. Prior research has focused on SEM parameter estimation with IVs when indicators were continuous and normally distributed. Much less is known about how estimators function in the presence of categorical indicators, which are commonly used in the social sciences, such as with cognitive and affective instruments. In this study, there was specific interest in comparing the 2-stage least squares (2SLS) estimator and its categorical variant to other recommended estimators. This study compares the performance of several estimation approaches for fitting structural equation models with categorical indicator variables when IVs are necessary to obta...
Histopathology of the subretinal fibrosis and uveitis syndrome

A chorioretinal biopsy was obtained from a patient with subretinal fibrosis and chronic uveitis. The biopsy specimen was analyzed by conventional light and electron microscopy and by immunohistochemical methods. These demonstrated a markedly inflamed choroid with a predominance of B cells and plasma cells. Complement and IgG were deposited above Bruch's membrane. The subretinal fibrosis tissue contained islands of cells with retinal pigment epithelial characteristics; however, some of these cells demonstrated surface determinants of Muller cells. There were no circulating antiretinal antibodies detected nor could virus be cultured from the biopsy specimen. The clinical appearance of this entity is distinctive and consists of a chronic posterior uveitis with transient initial yellow-white deep retinal lesions and the later development of large white subretinal fibrotic areas. The EOG is markedly decreased. We hypothesize that the immunologic events involved in this entity include antibody production with immunoglobulin and complement deposition leading to retinal and retinal pigment epithelial destruction and a subretinal fibrous proliferation.
Toward the characterization of upper tropospheric clouds using Atmospheric Infrared Sounder and Microwave Limb Sounder observations

[1] We estimate the accuracy of cloud top altitude (Z) retrievals from the Atmospheric Infrared Sounder (AIRS) and Advanced Microwave Sounding Unit (AMSU) observing suite (ZA) on board the Earth Observing System Aqua platform. We compare ZA with coincident measurements of Z derived from the micropulse lidar and millimeter wave cloud radar at the Atmospheric Radiation Measurement (ARM) program sites of Nauru and Manus islands (ZARM) and the inferred Z from vertically resolved Microwave Limb Sounder (MLS) ice water content (IWC) retrievals. The mean difference in ZA minus ZARM plus or minus one standard deviation ranges from −2.2 to 1.6 km ± 1.0 to 4.2 km for all cases of AIRS effective cloud fraction (fA) > 0.15 at Manus Island using the cloud radar only. The range of mean values results from using different approaches to determine ZARM, day/night differences, and the magnitude of fA; the variation about the mean decreases for increasing values of fA. Analysis of ZARM from the micropulse lidar at Nauru Island for cases restricted to 0.05 ≤ fA ≤ 0.15 indicates a statistically significant improvement in ZA − ZARM over the cloud radar-derived values at Manus Island. In these cases the ZA − ZARM difference is −1.1 to 2.1 km ± 3.0 to 4.5 km. These results imply that the operational ZA is quantitatively useful for constraining cirrus altitude despite the nominal 45 km horizontal resolution. Mean differences of cloud top pressure (PCLD) inferred from coincident AIRS and MLS ice water content (IWC) retrievals depend upon the method of defining AIRS PCLD (as with the ARM comparisons) over the MLS spatial scale, the peak altitude and maximum value of MLS IWC, and fA. AIRS and MLS yield similar vertical frequency distributions when comparisons are limited to fA > 0.1 and IWC > 1.0 mg m−3. Therefore the agreement depends upon the opacity of the cloud, with decreased agreement for optically tenuous clouds. Further, the mean difference and standard deviation of AIRS and MLS PCLD are highly dependent on the MLS tangent altitude. For MLS tangent altitudes greater than 146 hPa, the strength of the limb technique, the disagreement becomes statistically significant. This implies that AIRS and MLS “agree” in a statistical sense at lower tangent altitudes and “disagree” at higher tangent altitudes. These results provide important insights on upper tropospheric cloudiness as observed by nadir-viewing AIRS and limb-viewing MLS.
Correlating the Chemical and Physical Properties of a Set of Heavy Oils from around the World

Variations in the viscosity and other physical properties of heavy oils are poorly understood. The viscosities measured for different heavy oils can vary by orders of magnitude even at the same API gravity, which is the standard metric for lighter oils. Heavy oils are viscoelastic materials, and the shear modulus and the viscosity are coupled. Understanding what controls heavy oil viscosity will provide insight into what controls heavy oil shear modulus. Therefore, using rheology, ultrasonic measurements and molecular beam mass spectroscopy (MBMS) the physical and chemical properties of seven heavy oils from around the globe are explored. The viscoelastic nature of the oils is quantified as a function of temperature. Overall, the heavy oil samples show little correlation between the viscosity or shear modulus and the API gravity, separate resin content or separate asphaltene content as measured from SARA analysis. However, the total resin plus asphaltene content collapses the viscosity and modulus values to provide empirical relations between these quantities. Also, a partial least squares regression analysis provides tight correlations for the chemical signatures from the MBMS. The rapid and quantitative nature of the MBMS make it an attractive substitute for the inconsistencies endemic to SARA analysis.
On the Evolution of Solution Spaces Triggered by Emerging Technologies

Abstract The term solution space is widely used in the engineering community; yet there is little known about their evolution. Theoretical research in the field of systems science indicates that requirements can only reduce the solution space. Yet, some authors state that on the contrary requirements can be used to expand to or open new solution spaces. Furthermore, some practitioners defend that the requirement to use a previously nonexistent technology would actually increase the solution space or move it to a new area, while others state that more requirements make life more difficult. Who is right then? The present paper provides initial answers to this question using systems theory. In order to achieve this, the present paper differentiates between various types of solutions spaces, which depend on the systems they include. Finally, the paper provides practical examples to showcase the results of the theoretical findings within real contexts.
Hypoxia Attenuates Insulin-Induced Proliferation and Migration of Human Diabetic Infrapopliteal Vascular Smooth Muscle Cells

The proliferative effects of insulin on infrapopliteal vascular smooth muscle cells (VSMCs) have been established. We examined the effect of hypoxia in the presence and absence of insulin on the proliferation and migration of human diabetic infrapopliteal VSMCs in vitro. VSMCs isolated from the infrapopliteal arteries of male diabetic patients of identical disease and clinical patterns undergoing below-knee amputation were harvested and grown to subconfluence. Cells were then exposed to control medium (M199/1% fetal bovine serum/2% antibiotic-antimycotic) or control medium with 100 ng/mL insulin in oxygen concentrations of 17% (normoxia), 5%, and 1%. Cellular proliferation was assayed using [methyl-3H]-thymidine incorporation. Migration assays were performed using the Corning Costar Transwell® system. Lactate dehydrogenase was assayed and compared among groups as a marker for cytotoxicity. VSMCs in normoxic conditions (17%) had a significant increase in both proliferation (100 ± 6.5% vs. 124 ± 4.7%, p = 0.007) and migration [73.2 ± 9.3 vs. 118.1 ± 14.9 cells/4 high-power fields (HPF), p = 0.03] when exposed to insulin. Of cells exposed to insulin, those at both 5% (75.9 ± 7.9%, p = 0.0001) and 1% (73.6 ± 4%, p < 0.0001) hypoxia proliferated at a significantly decreased rate compared with cells at normoxia (124 ± 4.7%). Migration of these insulin-exposed cells was significantly decreased at 1% hypoxia (63.1 ± 9.0 cells/4HPF) compared to those at normoxia (118.1 ± 14.9 cells/4HPF, p = 0.006) and 5% hypoxia (101.2 ± 10.0 cells/4HPF, p = 0.01). There were no significant differences in migration between cells at normoxia and 5% hypoxia. Finally, hypoxia and insulin exerted no significant effect on cytotoxicity. The proliferative and promigratory effects of insulin on diabetic VSMCs are attenuated in hypoxic conditions in a manner unrelated to cytotoxicity.
HEAVY METAL CONCENTRATIONS IN KIDNEYS OF ESTUARINE RACCOONS FROM FLORIDA

Concentrations of lead, zinc and cadmium in the kidneys of 14 adult raccoons from an estuarine environment were determined. The mean concentrations in ppm wet weight and standard deviation for the metals were lead—0.47 ± 0.22, zinc —75.88 ± 16.54 and cadmium—2.48 ± 1.66.
Connective tissue growth factor is expressed by hyperproliferative keratinocytes during reepithelialization of full thickness wounds

INTRODUCTION: This study presents the new finding that connective tissue growth factor (CTGF/CCN2) is expressed by hyperproliferating keratinocytes during reepithelialization. CTGF/CCN2 is a marker and mediator of fibrosis, regulating important cellular events during wound healing. There has been contradicting data regarding whether CTGF/CCN2 is expressed by epidermis or not. This study uses a well-established porcine wound model to investigare the expression of CTGF/CCN2 during epithelialization of full-thickness wounds.
Electrical characterization and water sensitivity of Sr2Fe1.5Mo0.5O6−δ as a possible solid oxide fuel cell electrode

Abstract Sr2Fe1.5Mo0.5O6−δ (SFMO) powders were synthesized by combustion synthesis. Porous samples were formed by uniaxial pressing of powder compacts and sintering in air. Electrical conductivity was measured by a four-point DC technique over a temperature range from 200 °C to 800 °C in air and in hydrogen. Crystal structures were investigated by X-ray diffractometry. Stability of powder samples was investigated in H2O-containing atmospheres. It was observed that Sr2Fe1.5Mo0.5O6−δ was stable at 800 °C in water-containing atmospheres. However, it reacts with water at low temperatures. Reaction of Sr2Fe1.5Mo0.5O6−δ (SFMO) with water at low temperatures is a potential shortcoming of this material for application in solid oxide fuel cells (SOFC) due to concerns regarding degradation of the electrodes at low temperatures during cycling.
Deoxygenation of allylic carbinolamides and related alcohols by acidic sodium cyanoborohydride: Scope and limitations

Acidic sodium cyanoborohydride reduces allylic and other substituted carbinolamides to the corresponding deoxygenated compounds, whereas other similar alcohols are unreactive or undergo alternative transformations.
New techniques for the characterization of orientation in semicrystalline polymer moldings

This paper describes new techniques for evaluating orientation in polymer moldings. Injection moldings of isotactic polypropylene, a semicrystalline polymer, have been used to demonstrate the analytical procedures.
Lead-induced hypertension is not associated with altered vascular reactivity in vitro.

In confirmation of a previous study (Am J Hypertens 1993;6:723), mean arterial blood pressure (MBP), as determined by tail cuff plethysmography, was found to be significantly elevated in Sprague-Dawley rats after 3 months of feeding 0.48 mmol/L (100 ppm) lead acetate/day (144 ± 3.3 [SEM], in lead-treated [L] v 107 ± 3.3 mm Hg in controls [C], P < .001). Thoracic aorta was excised from L and C animals (n = 6). Segments were suspended in tissue baths with Krebs’ bicarbonate solution, then tested sequentially for vasoreactivity to 68 mmol/L K+, followed by graded concentrations of phenylephrine (PE), 0.01 to 0.3 μmol/L, acetylcholine (Ach), 0.001 to 3 μmol/L, nitroprusside (SNP), 0.0001 to 0.1 μmol/L, norepinephrine (NE), 0.001 to 300 μmol/L. There were no differences between L and C animals with respect to either vasoconstrictors (PE and NE) or vasodilators (Ach and SNP). The tissue levels of cGMP measured with and without phosphodiesterase inhibition, and in the absence and presence of either Ach or SNP, were comparable in the two groups. We conclude that the intrinsic vascular responsiveness is unchanged in lead-treated animals. The elevation of MBP is due to the presence of circulating factor(s) and hemodynamic changes.
Defluorination: A possible mechanism of detoxification in rats exposed to fluoroacetate

Abstract An earlier study described a defluorinating system in the 105 000 × g supernatant fraction of rat liver which is stimulated in vitro by glutathione and inhibited by maleate. This work suggested the possible role of this defluorinating system in the detoxification of fluoroacetate in vivo. The current study reports the enhanced toxicity of fluoroacetate in animals in which liver glutathione has been depleted. Diethylmaleate pretreatment was found to reduce liver glutathione levels to 10% of control values 30 min after dosing. In animals pretreated with diethylmaleate the LD 50 of fluoroacetate was reduced by 35%. Increased toxicity of fluoroacetate with depletion of liver glutathione concentrations is consistent with a protective role for the glutathione requiring fluoroacetate defluorinating system in rat liver.
Guidelines For Extending the Tissue Plasminogen Activator Treatment Window for Ischemic Stroke

To the Editor: The anticipated recently published guidelines, regarding extending the tissue plasminogen activator (tPA) treatment window for ischemic stroke, are sure to garner much attention and discussion within the United States.1 Largely based on the European Cooperative Acute Stroke Study (ECASS) III trial results, the newly proposed 3- to 4.5-hour tPA treatment guidelines appropriately exclude patients >80 years, those with a baseline National Institutes of Health Stroke Scale score >25, and …
International development management: A Northern perspective

This article reviews international development management (DM) from a Northern (primarily though not exclusively US-based) perspective, identifies lessons learned from experience, and discusses new challenges. The primary data sources are an on-line survey of DM scholars and practitioners, and the results of a focus group discussion. Survey respondents expressed dismay that the lessons from theory and experience have failed to penetrate the world of practice (largely due to political and bureaucratic constraints). They were generally pessimistic about DM's relevance and effectiveness in the face of new challenges. Our analysis points to implications for DM as a discipline, and examines the development manager as activist, the evolution of politics within DM, and DM as an art. Identified lessons related predominantly to DM's process and values dimensions, suggesting these may best define DM's unique contours. In response to the perceived absence of learning and to new challenges, research participants issued a call for development manager activism to speak truth to power, promote DM values, educate new actors and the public, and mentor and train newcomers to the field. This study underscores Northern-based development managers' commitment to the profession, including affirmation of the ongoing utility and relevance of DM's knowledge and lessons, and its underlying values of self-determination, social equity, and empowerment. Copyright © 2010 John Wiley & Sons, Ltd.
A mechanistic study on the formation of silver nanoplates in the presence of silver seeds and citric acid or citrate ions.

The world on a plate: In addition to their role as a capping agent that selectively binds to the {l_brace}111{r_brace} faces of silver, the carboxylate group can coordinate with Ag+ ions to form complexes and thus substantially reduce the reduction rate of Ag+ ions, leading to the formation of silver seeds with both twin planes and stacking faults.
Isotopic Tracer Studies of Thiophene Desulfurization Reactions Using Hydrogen from Alkanes on H-ZSM5 and Co/H-ZSM5

Abstract Reaction pathways for the desulfurization of thiophene using alkanes as hydrogen sources were probed by measuring the chemical and isotopic composition of products formed from 13 C-labeled C 3 H 8 and unlabeled C 4 H 4 S mixtures on H-ZSM5 and Co/H-ZSM5. Aliphatic hydrocarbons formed only from propane carbon atoms while aromatic molecules contained carbon atoms from both propane and thiophene. Hydrogen-deficient thiophene and thiophene-derived species react with surface hydrogen and alkenes formed from propane and desorb as unreactive aromatics, in steps that lead to the irreversible exit of alkenes from oligomerization-cracking cycles. These steps remove kinetic bottlenecks in thiophene desulfurization resulting from the irreversible formation of strongly adsorbed unsaturated species, which cannot desorb without reactions with hydrogen or hydrogen-rich surface species. This kinetic coupling between alkane and thiophene reactions leads to the observed concurrent increase in the rates of both propane aromatization and thiophene desulfurization compared with those achieved with each pure reactant. The scavenging of unsaturated intermediates formed via thiophene decomposition using hydrogen or hydrogen-rich intermediates formed from propane decreases the rate of bimolecular Diels–Alder reactions, which lead to larger organosulfur compounds and to low H 2 S selectivity. As a result, H 2 S selectivities are higher and deactivation rates are lower when propane is present as a co-reactant during reactions of thiophene.
Chronic Vitamin A Status and Acute Repletion with Retinyl Palmitate Are Determinants of the Distribution and Catabolism of all-trans-Retinoic Acid in Rats

The relation between vitamin A (VA) nutritional status and the metabolism of all-trans-retinoic acid (RA) is not well understood. In this study, we determined the tissue distribution and metabolism of a test dose of [ 3 H]-RA in rats with graded, diet-dependent, differences in VA status. The design included 3 groups, designated VA-deficient, VA-marginal, and VA-adequate, with liver total retinol concentrations of 9.7, 35.7 and 359 nmol/g, respectively, (P VA-marginal > VA-deficient, P < 0.05). Moreover, supplementation of VA-deficient rats with RP reduced the metabolism of [ 3 H]-RA, similar to that in VA-adequate or VA-marginal rats. Liver retinol concentration, considered a proxy for VA status, was correlated (P < 0.05) with [ 3 H]-RA metabolites in liver (R 2 = 0.54), plasma (R 2 = 0.44), lung (R 2 = 0.40), intestine (R 2 = 0.62), and all combined (R 2 = 0.655). Overall, the results demonstrate close linkage between dietary VA intake, hepatic storage of VA, and the degradation of RA and suggest that measuring plasma retinoid metabolites after a dose of RA may provide insight into the metabolism of this bioactive retinoid by visceral organs.
Analysis of receptor-ligand interactions using nitrocellulose gel transfer: Application to Torpedo acetylcholine receptor and alpha-bungarotoxin

Abstract A nitrocellulose-gel transfer technique has been adapted to study the interaction of a polypeptide ligand with individual receptor subunits. The acetylcholine receptor isolated from Torpedo californica has been separated into its subunits by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transferred in a renaturing environment to nitrocellulose sheets. The sheets were incubated with 125 I-alpha-bungarotoxin and autoradiographed. A single receptor polypeptide, the alpha subunit (40K) bound the labeled toxin. This binding was demonstrated to be both saturable and specific, although the affinity of 125 I-alpha-bungarotoxin ( K D , 165 n m ) and the potency of d -tubocurarine to displace this binding (IC 50 , 1 m m ) were both reduced by several orders of magnitude when compared to the native receptor.