cssi/SciSciGPT-SciSciNet huggingface dataset:
A molecular modeling study of entropic and energetic selectivities in Air separation with glassy polymers

Air separation is challenging due to the similarities in the sizes and energetics of oxygen and nitrogen. Although polymer membrane-based technology has achieved some success in replacing conventional air separation methods, the effectiveness of polymers has been shown to fall short of the economically attractive region occupied by inorganic microporous materials. Koros and co-workers have recently proposed that this lack of performance is a manifestation of the low entropic selectivity in polymers, possibly due to chain mobility or free volume effects. In this work, we address the effects of chain mobility on selectivity using molecular models and transition-state theory. We employ the methodology recently developed by Greenfield and Theodorou (Macromolecules 1998, 31, 7068) in which the polymer degrees of freedom can be explicitly included in the hopping rate calculations. About 100 oxygen and nitrogen jump events are studied in three different glassy polypropylene configurations. To examine the effects of polymer rigidity, two separate cases are considered for each jump; in the first case, the polymer model is held completely rigid during the event, while in the second the polymer torsional degrees of freedom are allowed to participate. The results show that the effects of polymer flexibility are reflected most significantly in the energy barriers, with the entropy barriers only marginally affected. Whereas the energetic selectivity can be reduced by 4 orders of magnitude in going from the rigid model to the flexible one, the entropic selectivity generally shows little change. The results are discussed in the context of current experimental and theoretical understanding of these systems.
Velocity effect on electronic-antifouling technology to mitigate mineral fouling in enhanced-tube heat exchanger

The purpose of the present study was to investigate the effect of flow velocity on an electronic-antifouling (EAF) treatment, which was considered to mitigate mineral fouling in a heat exchanger with cooling-tower water. Nine different tests were conducted with no-blowdown: six runs with an in-line EAF treatment and three runs with the EAF treatment at a side-stream loop. The flow velocities tested were 0.6, 1.2, 1.5 and 2.0 m/s. As the flow velocity was increased, the benefit of the in-line EAF treatment decreased. At a flow velocity of 0.6 m/s, the fouling resistance decreased by 80% in the case with the EAF treatment compared with that in the no-treatment case for both in-line and side-stream EAF treatments.
Comparative evaluation of dual Scheimpflug imaging parameters in keratoconus, early keratoconus, and normal eyes

Purpose To determine the efficacy of various parameters measured by dual Scheimpflug imaging technology in differentiating eyes with keratoconus or early keratoconus from normal eyes. Setting Cornea Service, Wills Eye Institute, Philadelphia, Pennsylvania, USA. Design Comparative case series. Methods A retrospective evaluation was performed of the parameters provided by the Galilei dual Scheimpflug analyzer in keratoconus, early keratoconus, and normal eyes. Logistic regression and receiver operating characteristic curve analysis were used to compare the mean values and to calculate the sensitivity and specificity of these parameters. Results Many parameters were statistically significantly different between keratoconus and normal eyes compared with early keratoconus eyes (P Conclusion Total corneal power, anterior curvature, posterior curvature, pachymetry, and corneal aberration data generated from the dual Scheimpflug analyzer showed promising results in differentiating keratoconus and early keratoconus eyes from normal eyes. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.
Rethinking mega-project development strategies: A case study of the Central Artery/Tunnel Project

For the majority of the last century, infrastructure development and management has focused primarily upon capital construction. In addition, a substantial amount of the financing for infrastructure, particularly within the US, has come from federal sources as evidenced by the Interstate Highway System Program and the EPA Construction Grants Program. The proclivity to focus upon the capital development cycle and the reliance upon federal funding have generally limited innovation in approaches to infrastructure development and minimized the importance of lifecycle management. However, new methods for both delivering and financing infrastructure have experienced a rebirth over roughly the last two decades. Integrated delivery strategies such as design-build-operate have increased the emphasis upon viewing constructed facilities as systems and have forced the recognition that sustaining these facilities requires more than just the initial capital investment. Unfortunately, new delivery and financing techniqu...
Ontogeny of Dopamine Daily Rhythms within Rabbit Brainstem Regions

To examine the development of daily variations in dopamine levels, we measured dopamine concentrations within five distinct brainstem regions in 3- and 21-day-old, and adult rabbits at 09.30, 15.30, 21.30 and 03.30 h. Dopamine was measured by radioenzymatic assay and the dopamine concentration was expressed relative to wet tissue weight. In addition to defining the presence of a daily variation in the dopamine concentration in the whole brainstem, we were interested in identifying brainstem region-specific differences in this daily variation. Our data suggest that daily variations in dopamine concentrations are established by 3 days of life. Analysis of gross brainstem daily variation data suggest a peak in the dopamine concentration during the early light phase (09.30 h) for 3-day-old animals in contrast to a late light phase peak (15.30 h) for 21-day-old animals. Adult animals showed a peak in the early dark phase (21.30 h). These gross daily variations reflect the net sum of distinct region-specific patterns in the dopamine concentration. Analysis by region reflects a region-specific ontogeny in the development of daily variations for dopamine. Dopamine is involved in cardiorespiratory regulation. The observed developmental patterns may relate to the maturation and integration of these physiologic processes.
Ultrastructure of four human germ cell tumor-derived cell lines: effect of 12-O-tetradecanoyl phorbol-13-acetate.

AbstractCells derived from human germ cell tumors (HGCT) are potential models for the study of human embryonic differentiation. Differentiation in four HGCT-derived lines (1618K, 833KE, 1777Ndif, 2806B) was examined by light and electron microscopy, after exposure of cells to dimethyl sulfoxide (DMSO) and 12-0-tetradecanoyl phorbol-13-acetate (TPA). In line 1618K, the effect of retinoic acid was also examined. After exposure to TPA, the cells of line 1618K had a loss of microvilli, an increased amount of nuclear heterochromatin, and an increase in the number of cytoplasmic vacuoles. The cells of line 833KE exposed to TPA showed only an increase in cytoplasmic vacuoles. No changes were observed in any cell line after exposure to DMSO. Similarly no changes were observed in 1618K after exposure to retinoic acid. These findings indicate that DMSO and retinoic acid are not effective inducers of differentiation in these HGCT-derived cell lines. Thephorbol ester, TPA, appears to induce differentiation of some HG...
Using mobile phones to simulate pulse oximeters: gait analysis predicts oxygen saturation

Widespread availability of mobile devices is leading revolution in health monitoring. Smartphones have demonstrated strong potential as ubiquitous monitors, but it is still unclear what vital signs can be monitored. We present a novel machine learning model to track oxygen saturation from phone sensors. Oxygen saturation is perhaps the major composite vital sign, widely used as a single measure of health status during medical procedures. We compute spatio-temporal gait parameters from phone sensor data, then use these to predict oxygen saturation with a trained model. We compare alternative approaches in each step of model training to discover optimal solutions. The validation shows training models on cohorts performs better than training a universal model. We ran unconstrained 6 minute walk tests on 15 senior pulmonary patients to predict oxygen saturation. The absolute error rate is about 1% for the cohort models and about 2% for the universal model. This can be compared to the 1% resolution of the pulse oximeter serving as standard and the 4% drop in values signifying desaturation. We also find that characteristic patterns in oxygen saturation as predicted correlate closely with the pulmonary function status. Thus smart phones have great potential to monitor desaturation in chronic patients.
Wave drag by three‐dimensional mountain lee‐waves in nonplanar shear flow

The effect of both cross-wind and vertical shear of the basic flow are considered in a linear, hydrostatic model of stationary, mountain lee-waves in a stably stratified airstream. Analytical solutions are first determined for a constant lapse rate basic-state. A solution corresponding to a cross-wind variation, represented by the hyperbolic secant profile, is compared with a constant flow over the same isolated hill. In the former case, wave-energy is trapped by the background shear. This effect is responsible for a greater wave-drag on the airstream than the drag produced in the constant wind case. However, these values of the wave-drag are always less than the drag exerted by two-dimensional waves over a ridge. A two-layer model is then considered, in order to examine the effect of a stable stratosphere over a less stable troposphere. The results show that the drag is sensitive to the phase difference between the transmitted and reflected waves in the lower layer. This sensitivity is more pronounced when cross-stream shear of the basic flow is taken into account. Finally, the relationship between the present model dynamics and the mechanism suggested for the dynamics of wave-induced downslope winds, presented by Klemp & Lilly, is pointed out. DOI: 10.1111/j.2153-3490.1976.tb00678.x
Modeling of eicosanoid fluxes reveals functional coupling between cyclooxygenases and terminal synthases.

Eicosanoids, including prostaglandins (PG) and leukotrienes, are lipid mediators derived from arachidonic acid. A quantitative and biochemical level understanding of eicosanoid metabolism would aid in understanding the mechanisms that govern inflammatory processes. Here, we present a combined experimental and computational approach to understanding the biochemical basis of eicosanoid metabolism in macrophages. Lipidomic and transcriptomic measurements and analyses reveal temporal and dynamic changes of the eicosanoid metabolic network in mouse bone marrow-derived macrophages (BMDM) upon stimulation of the Toll-like receptor 4 with Kdo2-Lipid A (KLA) and stimulation of the P2X7 purinergic receptor with adenosine 5′-triphosphate. Kinetic models were developed for the cyclooxygenase (COX) and lipoxygenase branches of arachidonic acid metabolism, and then the rate constants were estimated with a data set from ATP-stimulated BMDM, using a two-step matrix-based approach employing a constrained least-squares method followed by nonlinear optimization. The robustness of the model was validated through parametric sensitivity, uncertainty analysis, and predicting an independent dataset from KLA-primed ATP-stimulated BMDM by allowing the parameters to vary within the uncertainty range of the calculated parameters. We analyzed the functional coupling between COX isozymes and terminal enzymes by developing a PGH2-divided model. This provided evidence for the functional coupling between COX-2 and PGE2 synthase, between COX-1/COX-2 and PGD2 synthase, and also between COX-1 and thromboxane A2 synthase. Further, these functional couplings were experimentally validated using COX-1 and COX-2 selective inhibitors. The resulting fluxomics analysis demonstrates that the “multi-omics” systems biology approach can define the complex machinery of eicosanoid networks.
Solid-state disk amplifiers for fusion-laser systems

We review the design, performance, and operation of large-aperture (10-46 cm) solid-state disk amplifiers for use in laser systems. We present design data, prototype tests, simulations, and projections for conventional cylindrical pump-geometry amplifiers and rectangular pump-geometry disk amplifiers. The design of amplifiers for the Nova laser system is discussed.
Hydrothermal Synthesis and Characterization of a Metal–Organic Framework by Thermogravimetric Analysis, Powder X-ray Diffraction, and Infrared Spectroscopy: An Integrative Inorganic Chemistry Experiment

This advanced undergraduate laboratory experiment involves the synthesis and characterization of a metal–organic framework with microporous channels that are held intact via hydrogen bonding of the coordinated water molecules. The hydrothermal synthesis of Co3(BTC)2·12H2O (BTC = 1,3,5-benzene tricarboxylic acid) is carried out using one of four different reactors (stainless steel, microwave, polypropylene bottle, or sealed glass ampules) and the products are evaluated and compared using thermogravimetric analysis, powder X-ray diffraction, and IR spectroscopy. Powder X-ray diffraction is also used to monitor the changes in structure of the framework during the partial or complete removal of the associated water molecules, as well as after reabsorption of water.
North Atlantic climate variability: The role of the North Atlantic Oscillation

Abstract Marine ecosystems are undergoing rapid change at local and global scales. To understand these changes, including the relative roles of natural variability and anthropogenic effects, and to predict the future state of marine ecosystems requires quantitative understanding of the physics, biogeochemistry and ecology of oceanic systems at mechanistic levels. Central to this understanding is the role played by dominant patterns or “modes” of atmospheric and oceanic variability, which orchestrate coherent variations in climate over large regions with profound impacts on ecosystems. We review the spatial structure of extratropical climate variability over the Northern Hemisphere and, specifically, focus on modes of climate variability over the extratropical North Atlantic. A leading pattern of weather and climate variability over the Northern Hemisphere is the North Atlantic Oscillation (NAO). The NAO refers to a redistribution of atmospheric mass between the Arctic and the subtropical Atlantic, and swings from one phase to another producing large changes in surface air temperature, winds, storminess and precipitation over the Atlantic as well as the adjacent continents. The NAO also affects the ocean through changes in heat content, gyre circulations, mixed layer depth, salinity, high latitude deep water formation and sea ice cover. Thus, indices of the NAO have become widely used to document and understand how this mode of variability alters the structure and functioning of marine ecosystems. There is no unique way, however, to define the NAO. Several approaches are discussed including both linear (e.g., principal component analysis) and nonlinear (e.g., cluster analysis) techniques. The former, which have been most widely used, assume preferred atmospheric circulation states come in pairs, in which anomalies of opposite polarity have the same spatial structure. In contrast, nonlinear techniques search for recurrent patterns of a specific amplitude and sign. They reveal, for instance, spatial asymmetries between different phases of the NAO that are likely important for ecological studies. It also follows that there is no universally accepted index to describe the temporal evolution of the NAO. Several of the most common measures are presented and compared. All reveal that there is no preferred time scale of variability for the NAO: large changes occur from one winter to the next and from one decade to the next. There is also a large amount of within-season variability in the patterns of atmospheric circulation of the North Atlantic, so that most winters cannot be characterized solely by a canonical NAO structure. A better understanding of how the NAO responds to external forcing, including sea surface temperature changes in the tropics, stratospheric influences, and increasing greenhouse gas concentrations, is crucial to the current debate on climate variability and change.
On the Nature of The Liquid Expanded/Liquid Condensed Phase Transition in Monolayers of Polar Molecules.

During the liquid expanded/liquid condensed (LE/LC) phase transition, the long range repulsive interactions among fatty acid or phospholipid molecules induce the formation of a dispersion of LC islands (of almost the same size) as a superlattice in a continuous phase of LE molecules. Assuming that the transformation occurs at thermodynamic equilibrium, one demonstrates that, as the surface fraction of LC phase increases, the surface pressure π increases. Consequently, the LE/LC transition can have characteristics different from those of the conventional first order transitions.
Knowledge, motivation, and behavior patterns of the general public towards sun protection

The general public has long been educated about the harms of ultraviolet (UV) exposure and the benefits of photoprotection. Many organizations have worked in close collaboration to deliver the photoprotection message through a variety of programs. Most address the health-related consequences of UV radiation, although appearance-based strategies have also been initiated. As is common with preventative health measures, these intervention efforts have not resulted in meaningful changes in public behavior despite providing seemingly adequate knowledge to do so. Behaviors are often difficult to change on a societal, personal, and biological level. Within these categories, there are unique reasons for the unsatisfactory outcome with photoprotection such as (1) tan is perceived as beautiful, (2) the knowledge conveyed is often superficial, (3) there is a lack of immediate risk/reward, and (4) UV has reinforcing effects on mood. We propose that better results could be achieved by creating interventions focused on demographic subsets of the population. Specific techniques include anti-tanning legislature, age or gender-based screening campaigns, anti-tan beauty campaigns, and UV photography. Future photoprotection messages should shift from purely promoting knowledge to inspiring improvements in behavior with targeted strategies.
Spirituality and quality of life in low‐income men with metastatic prostate cancer

Abstract Objective: To determine how spirituality is associated with health-related quality of life(HRQOL) in an ethnically diverse cohort of low-income men with metastatic prostate cancer.Methods: Eighty-six participants in a state-funded program that provides free prostatecancer treatment to uninsured, low-income men completed written surveys and telephoneinterviews containing validated measures of spirituality, and general and disease-speciﬁcHRQOL. Assessments were made following diagnosis of metastatic disease. We usedmultivariate analyses to assess the eﬀect of spirituality and its two subscales, faith andmeaning/peace, on HRQOL.Results: African American and Latino men, and men with less than a high-school educationhad the highest spirituality scores. Spirituality was signiﬁcantly associated with general anddisease-speciﬁc HRQOL. We also found a signiﬁcant interaction between faith and meaning/peace in the physical and pain domains.Conclusion: Greater spirituality was associated with better HRQOL and psychosocialfunction. Meaning/peace closely tracks with HRQOL. Higher faith scores, in the absence ofhigh meaning/peace scores, are negatively associated with HRQOL.Copyright r 2008 John Wiley & Sons, Ltd.Keywords: cancer; oncology; prostate cancer; metastatic; spirituality; quality of life
New material of “Trematochampsa” oblita (Crocodyliformes, Trematochampsidae) from the Late Cretaceous of Madagascar

(2009). New material of “Trematochampsa” oblita (Crocodyliformes, Trematochampsidae) from the Late Cretaceous of Madagascar. Journal of Vertebrate Paleontology: Vol. 29, No. 2, pp. 599-604.
In vivo evaluation of 188Re-labeled alpha-melanocyte stimulating hormone peptide analogs for melanoma therapy.

The purpose of our study was to optimize melanoma tumor uptake of 188Re-CCMSH and reduce its nonspecific kidney retention. Nephrotoxicity is often a serious problem associated with targeted radiotherapy, therefore, increasing the tumor/kidney uptake ratio of 188Re-CCMSH is crucial for optimizing its therapeutic efficacy. Structural modification of the peptide and amino acid co-infusion were investigated as strategies to improve the tumor/kidney uptake ratio of 188Re-CCMSH. The substitution of Lys11 with Arg11 was examined to determine if removal of lysine from the peptide would improve kidney clearance without sacrificing tumor uptake. The pharmacokinetics of 188Re-CCMSH and 188Re-(Arg(11))CCMSH were determined in B16/F1 murine melanoma-bearing C57 mice. Tumor uptake values of (188)Re-CCMSH and 188Re-(Arg(11))CCMSH were 15.03 +/- 5.20% ID/g and 20.44 +/- 1.91% ID/g at 1 hr postinjection and 1.94 +/- 0.47% ID/g and 3.50 +/- 2.32% ID/g at 24 hr postinjection. Renal retention of 188Re-(Arg(11))CCMSH was 11.79 +/- 1.29 ID/g and 3.67 +/- 0.51 ID/g at 1 hr and 4 hr postinjection, which was a greater than 50% reduction compared to 188Re-CCMSH. The Arg for Lys substitution in 188Re-(Arg(11))CCMSH resulted in improved tumor uptake and reduced kidney retention. Renal retention of both 188Re-CCMSH and 188Re-(Arg(11))CCMSH were significantly reduced by co-injection of 20 mg of L-lysine, L-arginine and a combination of L-lysine:L-arginine. Tumor/kidney uptake values for 188Re-CCMSH and 188Re-(Arg(11))CCMSH were maximally reduced by 52.9% and 46.3%, respectively. However, even with amino acid co-injection, the tumor/kidney ratio of 188Re-CCMSH was lower than that of 188Re-(Arg(11))CCMSH. Improved tumor uptake and reduced kidney retention of 188Re-(Arg(11))CCMSH will facilitate targeted irradiation of melanoma tumors while minimizing the dose to the kidneys.
Scaling Effective Education for the Poor in Developing Countries: A Report from the Field

Abstract Many school programs in developing countries have achieved scale but with varying quality. Conversely, some programs have achieved quality in one or two schools but have not achieved scale. This article describes an extensive field investigation of three education organizations in developing countries that have achieved both scale and quality: Bangladesh Rural Advancement Committee, Escuela Nueva in Colombia, and Pratham in India. The research led to the development of a framework of organizational characteristics and practices that are important for the successful scaling of effective education in impoverished regions. The three scaling levers—program, process, and passion—can also be effectively applied to other social enterprises addressing social issues in many industries.
Strategies to Reduce Bond-line Read-out in Adhesive Joined SMC Automotive Body Panels

Parameter sensitivity analysis on a 2D finite element model of adhesive-joined SMC hat/plate structure was performed to evaluate the relative impact of design, application, and material parameters on the bond-line read-out (BLRO) defect. Based on the sensitivity analysis and the ease of implementation, a list of strategies in the order of their effectiveness in reducing the BLRO defect is proposed. Choosing a low modulus, low cure temperature, and low shrinkage adhesive, raising the stiffness of the exterior SMC panel, and lowering the stiffness of the interior SMC panel in the regions around the bond-line were found to reduce the BLRO defect.
The atomic absorption determination of antimony,arsenic, bismuth, cadmium, lead, and tin in iron, copper,and zinc alloys with the graphite furnace

Abstract Antimony, arsenic, bismuth, cadmium, lead, and tin can be determined in metallurgical samples by flame atomic absorption spectrometry at levels of 0.005 wt%, but lower concentrations frequently necessitate preconcentration. The graphite furnace allows determination of these elements at concentrations 1–2 orders of magnitude lower than is possible with flame techniques. All six elements have detection limits at or below 1μg g −1 in a variety of alloys. Calibration for antimony and load was done with standards containing the principal component of the alloy as a synthetic matrix. Bismuth, cadmium, and tin could be determined accurately only by the standard addition method. Arsenic could be determined in iron alloys with synthetic standards, but standard additions were required for copper alloys.
Process design in a dynamic environment: Part I. A decomposition technique to study the stability of chemical engineering systems

The stability of various chemical engineering systems is studied through the use of vector Lyapunov functions. A decomposition technique is employed which reduces the problem to small, independent, free subsystems that can be analyzed through Lyapunov's second method. The stability characteristics of the overall system are then related to the behavior of a linear system which is easily analyzed.
Quality control of allergen extracts.

Although the article by Anderson and Baer presents complex and highly technical data, it has profound implications for the practicing allergist. As the authors point out, many have presented evidence that allergen extracts lose biologic activity after prolonged storage. Up to now, however, no one has documented quite so thoroughly the changes that occur in extracts while they wait on the shelf. It appears that the products furnished to allergists, more often than not, have undergone serious deterioration during the course of manufacturing, shipment, and storage. To state that as fact is not to disparage the efforts of manufacturers to make a potent and stable product. Biologic assays such as skin tests or histamine release simply are not applicable to every production lot of every allergen, and readily usable laboratory techniques have been a long time in development. Nor have the criteria for a potent product been agreed on by either the consumers (the allergist) or the controllers (the Food and Drug Administration in the U.S.). Proper control of the process of extraction, storage, and shipment depends on reasonably simple and reproducible assays that can be used to check the potency and identity of the product at each step during manufacture, but which do not put the price of the finished product beyond the pocketbook of the consumer. Such technology is now largely at hand and some combination of RAST inhibition, isoelectric
Frontal systems deficits in stimulant-dependent patients: Evidence of pre-illness dysfunction and relationship to treatment response

Abstract Background Frontal systems dysfunction is present in stimulant-dependent patients. However, it is unclear whether this dysfunction is a pre-morbid risk factor or stimulant-induced, is severe enough to be clinically relevant, and if it is relevant to treatment response. These questions were addressed using the Frontal Systems Behavior Scale (FrSBe), a reliable and valid self-report assessment of three neurobehavioral domains associated with frontal systems functioning (Apathy, Disinhibition, and Executive Dysfunction, summed for a Total), that assesses both pre- and post-morbid functioning, and has a specific cutoff for defining clinically significant abnormalities. Method Six sites evaluating 12-step facilitation for stimulant abusers obtained the FrSBe from 180 methamphetamine- and/or cocaine-dependent participants. Dichotomous treatment response measures included self-reported stimulant use, stimulant urine drug screens, and treatment completion. Results A substantial percentage of participants retrospectively reported clinically significant neurobehavioral abnormalities prior to lifetime stimulant abuse initiation (e.g., 67.5% on FrSBe-Total) with a significant increase in the proportion reporting such abnormalities for current functioning (86% on FrSBe-Total; p Conclusion These findings suggest that frontal systems dysfunction is present prior to stimulant-abuse onset and worsens with stimulant use. Disinhibition may be a prime target for intervention in stimulant-dependent individuals.
The Benefits of Pass-Fail Grading on Stress, Mood, and Group Cohesion in Medical Students

OBJECTIVE To objectively measure the effect of a pass-fail grading system on stress, mood, group cohesion, and test anxiety in medical students. PARTICIPANTS AND METHODS Beginning with the class of 2006, the Mayo Medical School, Rochester, Minn, changed the grading system for first-year courses from a 5-interval grading system to a pass-fail grading system. Students in the previous class of 2005, who were graded using a 5-interval system during their first year of medical school, were compared with students in the class of 2006. Using a prospective study design, the 2 groups were compared at the end of both the first year and the second year of medical school on the Perceived Stress Scale, Profile of Mood States, Perceived Cohesion Scale, Test Anxiety Inventory, and (after year 2) the United States Medical Licensing Examination Step 1. Data collection occurred in 2002 and 2003 with the class of 2005 and in 2003 and 2004 with the class of 2006. RESULTS Students graded with the pass-fail system had less perceived stress (median, 15.0 vs 21.0; P =.01) and greater group cohesion (median, 34.5 vs 30.0; P =.02) at the end of their second year of coursework than their 5-interval graded peers. The pass-fail group had better mood (median, 46.5) than the graded group (median, 64.0), but this difference was not statistically significant ( P =.07). No significant differences were found between the 2 groups in test-taking anxiety or in United States Medical Licensing Examination Step 1 board scores. CONCLUSION Pass-fail grading may reduce stress and increase group cohesion in medical students compared with traditional 5-interval grading.
Homeland security R&D budgets and conference overview

Homeland Security R&D budgets will be summarized with an emphasis on the FY 2007 and comparisons to FY 2006 and the proposed FY 2008 budget. A summary of the federal budget process is given with insights into the specific omnibus bill funding FY 2007 for most of the federal budget and the omnibus bill's impact on organizations included in the American Competitiveness Initiative. Projections for FY 2008 Homeland Security Research, as analyzed by AAAS, show that ~80% of R&D funding is outside the Department of Homeland Security. An overview of the conference includes insights into the Drinking Water Security, Border Security, Transportation Security (including an update from the MANPADS program office), Port and Harbor Security, Health Security, and Non-Intrusive Inspection Technologies sessions.
Si/Ge Semiconductor Saturable Bragg Reflectors for Integrated Mode-Locked Lasers

Silicon-Germanium saturable absorber mirrors at 1550 nm are demonstrated. The device is used to achieve stable, continuously mode-locked operation of an Er-Yb: glass laser centered at 1540 nm, generating 220 fs pulses.
Dynamic Evaluation of Matisse's 1935 Large Reclining Nude:

Forty non-artists and 16 art students rated the 22 in-progress states of Henri Matisse's great 1935 painting, Large Reclining Nude, on 26 survey items measuring several constructs: quality, origina...
Evaluation of a salt-fluxing residue as a potential potassium-magnesium fertilizer in the pacific northwest

The objective of this study was to evaluate a fluxing salt residue (slag) produced 1n large quantities by a Mg reclamation process as a potential K‐Mg nutrient source (41% KC1, 33% MgO and 3.2% MgC...
Stability effects of singularities in force-controlled robotic assist devices

Force feedback is being used as an interface between humans and material handling equipment to provide an intuitive method to control large and bulky payloads. Powered actuation in the lift assist device compensates for the inertial characteristics of the manipulator and the payload to provide effortless control and handling of manufacturing parts, components, and assemblies. The use of these Intelligent Assist Devices (IAD) is being explored to prevent worker injury, enhance material handling performance, and increase productivity in the workplace. The IAD also provides the capability to shape and control motion in the workspace during routine operations. Virtual barriers can be developed to protect fixed objects in the workspace, and regions can be programmed that attract the work piece to a certain position and orientation. However, the robot is still under complete control of the human operator, with the trajectory being determined and commanded using the judgment of the operator to complete a given task. In many cases, the IAD is built in a configuration that may have singular points inside the workspace. These singularities can cause problems when the unstructured trajectory commands from the human cause interaction between the IAD and the virtual walls and fixtures at positions close to these singularities. The research presented here explores the stability effects of the interactions between the powered manipulator and the virtual surfaces when controlled by the operator. Because of the flexible nature of the human decisions determining the real time work piece paths, manipulator singularities that occur in conjunction with the virtual surfaces raise stability issues in the performance around these singularities. We examine these stability issues in the context of a particular IAD configuration, and present analytic results for the performance and stability of these systems in response to the real-time trajectory modification of the human operator.
Growth studies of ferroelectric oxide layers prepared by organometallic chemical vapor deposition

Abstract Low pressure organometallic chemical vapor deposition was used to prepare ferroelectric thin films. Both the bismuth and the strontium titanate system were investigated. Under the optimal growth conditions phase pure, textured films could be prepared. The growth parameters which influenced composition and phase stability were examined.
Effects of pH on the environmental fate of [14C]aldicarb in an aquatic microcosm.

Abstract The role of pH in determining the environmental fate of [ 14 C]aldicarb was examined in an aquatic microcosm. Only minor amounts of the radiochemical were absorbed by aquatic organisms at any pH. Of the radioactivity absorbed, greater than 75% was rapidly metabolized and incorporated into tissues. Minor differences in the in vivo spectrum of aldicarb and metabolites as a function of pH were discerned for fish; the quantitative and qualitative distribution of aldicarb and its metabolites was identical for the other organisms across the pH levels. The most notable difference in metabolite spectrum appearing in the water as a function of pH was the absence of aldicarb sulfone at pH 4 on Day 6. In contrast, aldicarb sulfoxide was found as the major metabolite and aldicarb was completely lacking at all three pH levels. Since aldicarb sulfoxide is biologically active, disappearance of the parent compound does not eliminate hazard. The general effects of pH on the environmental fate of aldicarb are neglible on Day 6 but may be more pronounced at other time periods.
Response functions and the retarded surface plasmon for bounded jellium

Abstract The self-consistent retarded electrodynamic response of bounded jellium is analyzed for independent electrons in the infinite barrier model. Within the RPA, and for q ⪡ kF, a set of coupled integral equations is developed which can be solved for the response functions of the system. The retarded surface plasmon dispersion emerges immediately from this formalism.
Investigations of Alloying Elements and Rare Metals on the Hydrogen Content and Inclusion in Aluminum Alloy

The influences of alloying elements Mg, Zn and Cu and rare metals Ce, Er and mix rare metal (MRE) on the hydrogen content and inclusion in 1050 aluminum alloy were studied by optical microscope, scanning electronic microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results show that when adding 1wt.%Mg, 5wt.%Zn, 0.5wt.%Er and 0.5wt.%MRE into 1050 aluminum alloy, respectively, the decrements of density of the reduced pressure test (RPT) samples are 0.36g/cm3, 0.24g/cm3, 0.72g/cm3, and 0.24g/cm3, respectively. Mg and Er significantly increase the tendency of hydrogen adsorption in Al melt. The results of XRD analysis and microstructural observation indicate that the alloys adding Er contain more oxides and gas porosity.
Mixed gas transport study through polymeric membranes

Membrane permeation and separation characteristics of mixed gas/membrane systems are typically calculated from single-component transport parameters, namely, diffusion coefficients and solubility constants. In certain gas systems involving gaseous or vapor mixtures, where mass transport is affected by coupling effects or the competition of penetrants for unrelaxed free volume, such calculations can lead to erroneous estimates of the membrane separation efficiency. In this paper, we discuss the design and development of an experimental setup for observing mixed gas permeation through non-porous membranes. The novelty of the setup is the unique inline sampling interface which allows injection of permeate mixed gas samples for concentration analysis without introducing any leaks into the permeate volume. Also, a data cropping technique is introduced to elucidate the transport properties of gases through membranes under mixed gas permeation conditions. The method is employed in mixed gas permeation studies of a rubbery polymer, (PDMS), and a glassy polymer, (NEW-TPI), membranes, using different feed compositions of a CO2/CH4 binary gas system. The results show an absence of synergistic effects in gas permeation through the rubbery polymer, however, in the glassy polymer the transport parameters of each of the gases are highly affected by the presence of the other gas. Also, a change in the feed gas composition alters the separation properties of the glassy polymer.
Thermodynamic Modeling of Vapor−Liquid Equilibria in Mixed Aqueous−Organic Systems with Salts

A thermodynamic model is proposed for prediction of vapor-liquid equilibria (VLE) in mixed aqueous-organic solvents containing salts. The model is based on thermodynamic relations that include explicitly the effect of a solute on the activity coefficients of the cosolvents in the mixture. These relations are derived by integrating the multicomponent Gibbs-Duhem equation. The model requires the difference between the Gibbs free energy of formation of the pure salt and the Gibbs free energy of formation of this salt corresponding to the standard state in each of the pure cosolvents. Activities for the cosolvents in the salt-free mixture are also required. The new formalism is illustrated with predictions of VLE for a number of mixtures of water with methanol, ethanol, and propanol in the presence of different salts over the entire range of concentration. The model is able to predict quantitatively azeotropic compositions and their shift as a function of salt concentration.
Polyether ketones derived from bis[4-(4-fluorobenzoyl)phenyl]phenylphosphine oxide

Abstract A series of new poly(phosphine oxide ether ketone)s has been prepared from bis[4-(4-fluorobenzoyl)phenyl]phenylphosphine oxide (1) and various bisphenols by the aromatic nucleophilic substitution reaction in DMAc. Monomer 1 was readily prepared by Friedel–Crafts acylation from bis(4-chloroformylphenyl)phenylphosphineoxide and fluorobenzene. Film-forming polymers were produced which have inherent viscosities ranging from 0.76 to 1.32 dl/g. These polymers are thermally stable to more than 500°C in air and exhibit glass transitions at about 200°C. Water contact angles of these polymers ranged from 79 to 84°.
Analytic solutions of some coupled nonlinear equations

New analytic solutions for coupled nonlinear Schr\"odinger, coupled nonlinear equations of higher order, coupled Korteweg--de Vries, and coupled Boussinesq equations are presented. Applications to solitary waves, e.g., in birefringent optical fibers, are discussed.
The Kruskal-Katona method made explicit

Let Kc(e) = min |ΓX|, where the minimum is taken over all e-member families X of c-element subsets of a finite set S where ΓX is the family of (c−1)-element subsets of S contained in at least one member of X and where |ΓX| is the number of members in ΓX. J. B. Kruskal [5] and G. O. H. Katona [4] discovered independently an implicit method for calculating Kc(e). In this note a more explicit method is presented.
Nanofocusing of Optical Energy in Tapered Plasmonic Waveguides

We predict theoretically that surface plasmon polaritons propagating toward the tip of a tapered plasmonic waveguide are slowed down and asymptotically stopped when they tend to the tip, never actually reaching it (the travel time to the tip is logarithmically divergent). This phenomenon causes accumulation of energy and giant local fields at the tip. There are various prospective applications in nano-optics and nanotechnology.
Perceived and actual similarities in biological and adoptive families: Does perceived similarity bias genetic inferences?

Critics of the adoption method to estimate the relative effects of genetic and environmental differences on behavioral development claim that important biases are created by the knowledge of biological relatedness or adoptive status. Since the 1950s, agency policy has led to nearly all adopted children knowing that they are adopted. To test the hypothesis that knowledge of biological or adoptive status influences actual similarity, we correlated absolute differences in objective test scores with ratings of similarity by adolescents and their parents in adoptive and biological families. Although biological family members see themselves as more similar than adoptive family members, there are also important generational and gender differences in perceived similarity that cut across family type. There is moderate agreement among family members on the degree of perceived similarity, but there is no correlation between perceived and actual similarity in intelligence or temperament. However, family members are more accurate about shared social attitudes. Knowledge of adoptive or biological relatedness is related to the degree of perceived similarity, but perceptions of similarity are not related to objective similarities and thus do not constitute a bias in comparisons of measured differences in intelligence or temperament in adoptive and biological families.
Input Rates for a One-Handed Input Device (OHAI) for Chinese Text Entry

As computer technology has become ubiquitous in nature, designers must develop text-entry methods that can accommodate a variety of devices, cultures, and languages. This paper presents a study evaluating a One-HAnded Input (OHAI) device developed for mobile text-entry in Chinese. The device is a chorded keyboard system on which text is entered in Chinese using the pinyin system. Participants trained with the device for 10, 1-hour sessions. Their text-entry rates and their rate of input for individual chords were measured after each session. The Power Law of Practice was used to predict input rates after 100 hours of training. Predicted input rates approximate 16 characters per minute, approaching pinyin input rates on conventional keyboards. Input rates for individual chords were also measured in order that future iterations of the software may associate the most commonly used characters with the fastest-to-execute chords. The study also suggests several potential future improvements to the OHAI system, ...
The utility of the Beck anxiety inventory with inpatient adolescents

Abstract This study is the first to examine the reliability, convergent validity, and discriminant validity of a new adult self-report measure of “pure” anxiety, the Beck Anxiety Inventory (Beck et al., 1988; Beck & Steer, 1991), with adolescents (N = 80). The BAI appears readable for 14-year-old patients with average reading skills. It has high internal consistency (alpha = .94), acceptable item-total score correlations (M = .66), and moderate to high concurrent validity; that is, the BAI correlated significantly with clinician ratings (r = .40) and self-report (r = .58) measures of anxiety. The results of the BAI's ability to discriminate anxiety from depression were mixed, based on the method utilized to assess this relationship. Whereas the BAI demonstrated moderate discriminant validity with the clinician ratings, the BAI converged significantly with the self-report depression measure. Anxiety-disordered adolescents scored significantly higher (31.5) than adolescents with depressive disorders (13.1) on the BAI. Results demonstrate that the BAI can be used validly and reliably in clinical practice, as well as in research with severely disturbed adolescents.
The effects of social learning on the acquisition of cocaine self-administration

Background Social learning models of substance use propose that drug-use behaviors are learned by observing and mimicking the behavior of others. The aim of this study was to examine the acquisition of cocaine self-administration in three groups of experimentally naive rats: rats that were tested in isolation, rats that were tested in the presence of another rat that had access to cocaine and had previously been trained to self-administer cocaine, and rats that were tested in the presence of another rat that did not have access to cocaine.
Multiple Roles in Responding to Strategic Communications

Teaching communication to MBAs often involves focusing on corporate strategic discourse when student projects are intended to help companies move to a more advanced stage of development. This focus on corporate strategy—the language and concepts that concern the mission and direction that an organization should adopt—requires, in turn, that faculty enact several roles to assist students in developing their final assignments, strategic presentations, and reports. Faculty play the role of specialists in corporate strategy, communication specialists, and stand-ins for the primary audience(s) for these assignments. Working with students on these assignments underscores two important values in MBA education: providing students with the means to engage in discussion at the CEO level where decisions about the company’s strategic direction are made, and demonstrating to students that the strategic assignments they produce belong to a larger communication campaign for getting buy-in for corporate strategy. These t...
Oxygen isotope studies of zeolites—Stilbite, analcime, heulandite, and clinoptilolite: III. Oxygen isotope fractionation between stilbite and water or water vapor

Abstract The oxygen isotope fractionation between the aluminosilicate framework of stilbite and water vapor (or bulk water) was studied between 125 and 300°C. The fractionation factor for exchange between the channel water of stilbite and water vapor was determined at room temperature. At this temperature, the channel water of stilbite is enriched in 18O by 6%. relative to water vapor (and hence is depleted in 18O by 3%. relative to the liquid water). Reliable values of the fractionation between framework oxygen and water vapor were obtained only at 220°C and higher temperatures. At these temperatures, the fractionation is described by the equation: 1000 In α stilbite-water = −2.4 + 2.7 × 10 6 T 2 . The measured fractionation factors are similar to the fractionation factors in the albite-water system extrapolated from values measured at higher temperatures (≥ 350°C). This observation is consistent with the fact that the stilbite has the same Al Si ratio as albite.