cssi/SciSciGPT-SciSciNet huggingface dataset:
Identity, Equivalence and Reduction

In this chapter we will attempt to use our understanding of the logical structure of the empirical claims in theories of mathematical physics -the account developed in the first five chapters — to clarify some other questions about these theories. First, we will attempt to say, as precisely as we can, just what a theory of mathematical physics is. That is, we will attempt to give some general, and precise characterization of theories of mathematical physics. Once we have developed this characterization, we will employ it to investigate the properties of two relations — equivalence and reduction — that are commonly alleged to hold between some theories of mathematical physics. In the course of this discussion, we will have occasion to examine the Lagrangian and Hamiltonian formulations of particle mechanics as examples of theories of mathematical physics that are, in some sense, equivalent to the Newtonian formulation of particle mechanics. We shall also examine rigid body mechanics as an example of a theory which reduces to particle mechanics.
Hormones, cytokines and body composition : can lessons from illness be applied to aging ?

Loss of lean body mass (LBM) is a hall-mark of aging and of acute and chronic illness. Loss of more than 40% of lean mass is not compatible with life. The causes of loss of LBM in aging remain obscure, although changes in growth hormone production, physical activity and the cytokines interleukin-1β and tumor necrosis factor-α may play a role. The usefulness of a disease model based on rheumatoid arthritis (RA) is considered, in which all these changes occur to a greater degree and independently of age. RA is a common autoimmune condition in which cytokine production is increased, LBM is reduced and mortality is greatly accelerated
Point/Counterpoint: To Be or To Do: Is a Gifted Child Born or Developed?.

(2003). To be or to do: Is a gifted child born or developed?. Roeper Review: Vol. 26, No. 1, pp. 12-13.
Diurnal Variation in α-Melanocyte-Stimulating Hormone Content of Various Brain Regions and Plasma of the Texas Toad, Bufo speciosus

Abstract We measured the concentrations of α-melanocyte-stimulating hormone (α-MSH) in various brain regions as well as in the pituitary gland and plasma of the toad Bufo speciosus during a 24-hr light:dark cycle. There was significant diurnal variation of α-MSH concentrations in the hypothalamus and brainstem. In both areas α-MSH concentrations were highest during the scotophase . Peak α-MSH concentrations in the hypothalamus were observed at 21.00 and 05.00 hr, while a single peak in α-MSH concentrations was observed in the brainstem at 21.00 hr. In contrast, peak α-MSH concentrations in the plasma were observed during the photophase at 17.00 hr, when brain concentrations of α-MSH were low. There was no significant diurnal variation observed in the pituitary content of α-MSH throughout the 24-hr light:dark cycle. These data suggest that different mechanisms control hypothalamic and pituitary α-MSH cells in the toad during the 24-hr light:dark cycle.The fact that peak α-MSH concentration were observed in the hypothalamus during the activity period of the toad is consistent with the proposed role of α-MSH peptides in learning and memory processes.
Differentiation of cardiosphere-derived cells into a mature cardiac lineage using biodegradable poly(N-isopropylacrylamide) hydrogels.

A family of injectable and thermosensitive hydrogels suitable for myocardial injection was developed to deliver cardiosphere-derived cells (CDCs), an emerging and promising cell type for cardiac cell therapy. The hydrogels were based on polycaprolactone, N-isopropylacrylamide, 2-hydroxyethyl methacrylate and dimethyl-γ-butyrolactone acrylate. Atom transfer radical polymerization was used to synthesize hydrogels with a well-defined structure and well-controlled properties. The hydrogel solutions possessed thermal transition temperatures around room temperature and exhibited injectability suitable for myocardial injection. At 37 °C, the hydrogel solutions were capable of forming solid gels within 5s. This would allow the hydrogels to largely retain in the heart during injection. The hydrogels were highly flexible at body temperature with moduli matching those of the rat and human myocardium, and breaking strains higher than those of the myocardium, enabling them to respond synchronically with heart motion. The well-controlled polymer structure allowed for precisely controlling and decoupling water content and stiffness that affect cell differentiation. DNA assay demonstrated that CDCs proliferated in the 3D hydrogels during a 2-week culture period. CDCs maintained their colony formation capability in the hydrogel. Interestingly, hydrogels directed CDCs differentiation into mature cardiac lineage. At mRNA level, the mature cardiac specific transcript factors cardiac troponin T (cTnT) and cardiac myosin heavy chain (MYH6) were up-regulated, while the pre-mature cardiac marker GATA4 was down-regulated even after 1 day of encapsulation. CDC differentiation was interplayed by hydrogel stiffness and collagen in the hydrogel. Hydrogel with modulus ∼31 kPa was found to more significantly up-regulate cardiac expression than that with modulus ∼5 or ∼63 kPa. cTnT expression was largely regulated by both stiffness and collagen while MYH6 was mainly regulated by stiffness. Immunohistochemistry study showed that CDCs expressed cardiac troponin I and MYH6 proteins after 2 weeks of culture. These results demonstrate that the thermosensitive hydrogels not only possess physical properties suitable for myocardial injection, but also promote CDC proliferation and cardiac differentiation. These hydrogels represent potential candidates for delivery of CDCs into infarcted hearts.
The wolf, the tourist, and the recreational context: New opportunity or uncommon circumstance?

Abstract A conceptual framework composed of three factors: the wolf, the tourist, and the recreational context is proposed as a means of understanding the wolf as a tourist attraction. Wolf tourists, as a subgroup of nonconsumptive wildlife users, are primarily interested in viewing, hearing, and photographing animals. But wild wolves are elusive, difficult to see, and occur in low population densities. To meet the demands of tourists, wolves are tracked in the wild on foot or in the air, bounded with fences and radio collars and encouraged to respond to human howling. This paper describes techniques currently used to increase the visibility of wolves and arranges each of these along a continuum—from strategies that exert a great deal of control over wolves to those that do not. Wolf tourism is also observed to require the presence of a well developed wildlife recreation infrastructure. A case study of Ely, Minnesota and the newly constructed International Wolf Center are used as examples to show the rele...
Tides in the English Channel and Southern North Sea. A frequency domain analysis using model TEA-NL

Abstract The frequency-time finite element model TEA-NL is used to investigate tidal propagation and circulation in the English Channel and the southern North Sea, in the context of the Tidal Flow Forum benchmark. Quality of TEA-NL simulations, relative to both field data and simulations by other numerical models is discussed. Sensitivity analyses are performed with regard to the effect on accuracy of bottom friction, and the effect on computational cost of the strategy used to harmonically decompose and iterate non-linear loading terms in the shallow water equations.
Infections Related to Pregnancy

Infections in pregnancy and in the postpartum period represent an important knowledge base that emergency physicians should have. Being able to understand the risk that pregnancy-related infections have on maternal and fetal health in addition to the initiation of appropriate treatment for these infections is crucial. In the postpartum period, most infections (94%) are likely to manifest after hospital discharge; therefore, patients frequently present to the emergency department.
Static meson potentials

The potentials between static sources of meson fields are computed for various cases of interest. For isoscalar mesons, the interaction via a scalar-meson field is the well-known Yukawa potential; the interaction via an isoscalar vector-meson field is shown to have the expected Yukawa form when an appropriate Hamiltonian is used. For isovector mesons, which interact through non-Abelian current operators, numerical computations of the potential are presented for vector-meson field interactions. In contrast to the Abelian cases, the non-Abelian interactions are not the same as the one-meson-exchange potentials.
Impact of target probability on single-trial EEG target detection in a difficult rapid serial visual presentation task

In non-invasive brain-computer interface (BCI), the analysis of event-related potentials (ERP) has typically focused on averaged trials, a current trend is to analyze single-trial evoked response individually with new approaches in pattern recognition and signal processing. Such single trial detection requires a robust response that can be detected in a variety task conditions. Here, we investigated the influence of target probability, a key factor known to influence the amplitude of the evoked response, on single trial target classification in a difficult rapid serial visual presentation (RSVP) task. Our classification approach for detecting target vs. non target responses, considers spatial filters obtained through the maximization of the signal to signal-plus-noise ratio, and then uses the resulting information as inputs to a Bayesian discriminant analysis. The method is evaluated across eight healthy subjects, on four probability conditions (P=0.05, 0.10, 0.25, 0.50). We show that the target probability has a statistically significant effect on both the behavioral performance and the target detection. The best mean area under the ROC curve is achieved with P=0.10, AUC=0.82. These results suggest that optimal performance of ERP detection in RSVP tasks is critically dependent on target probability.
New inhibitors of aldose reductase: anti-oximes of aromatic aldehydes.

Aldose reductase is an NADPH-dependent enzyme which catalyzes the reduction of glucose to sorbitol. Specific potent inhibitors of aldose reductase are of potential pharmacological use because elevated levels of sorbitol produced by this enzyme in lens, peripheral nerve, retina, and renal glomeruli may be responsible for the pathogenesis associated with chronic diabetes. These inhibitors could also serve as probes of the mechanism of action of aldose reductase. anti-Oximes of aromatic aldehydes (e.g., benzaldoxime and 4-fluorobenzaldoxime) have proved to be effective inhibitors of aldose reductase rivaling pharmacological agents currently used to inhibit this enzyme in vivo. The kinetic patterns of inhibition in which benzyl alcohol is used as the oxidizable substrate suggest that the inhibition is due to the formation of a stable ternary complex composed of aldose reductase, NADP+, and the anti-oxime. Analogus ternary complexes are formed at the active site of horse liver alcohol dehydrogenase which is also inhibited by anti-oximes of efficient substrates.
Predicting Personal Growth and Happiness by Using Serious Leisure Model

From a serious leisure perspective, serious leisure involvement is closely associated with positive outcomes such as enhancement of self-image and self-expression, improved social relationships and positive social interactions. This study hypothesizes that serious leisure involvement may lead to personal growth and happiness. Using a structural model, this study explored the relationship between serious leisure qualities and personal growth and happiness among Taekwondo participants (N = 167). Structural equation modeling demonstrated that there are causal relationships between serious leisure qualities and personal growth and happiness. The findings of this study have extended the exiting body of knowledge in serious leisure literature by quantitatively testing that personal growth and happiness are additional indicators of serious leisure outcomes.
A practical approach for quantitative estimates of voxel-by-voxel liver perfusion using DCE imaging and a compartmental model

Voxel-by-voxel estimation of liver perfusion using nonlinear least-squares fits of dynamic contrast enhanced computed tomography or magnetic resonance imaging data to a compartmental model is a computational expensive process. In this report, a “linear” least-squares method for estimation of liver perfusion is described. Simulated data and the data from an example case of a patient with intrahepatic cancer are presented. Compared to the nonlinear method, the new method can improve computational speed by a factor of ∼ 400 , which makes it practical for use in clinical trials.
Jejunum or Stomach for the Pancreatic Anastomosis After Pancreaticoduodenectomy

Objective: The authors hypothesized that pancreaticogastrostomy is safer than pancreaticojejunostomy after pancreaticoduodenectomy and less likely to be associated with a postoperative pancreatic fistula. Summary Background Data: Pancreatic fistula is a leading cause of morbidity and mortality after pancreaticoduodenectomy, occurring in 10% to 20% of patients. Nonrandomized reports have suggested that pancreaticogastrostomy is less likely than pancreaticojejunostomy to be associated with postoperative complications. Methods: Between May 1993 and January 1995, the findings for 145 patients were analyzed in this prospective trial at The Johns Hopkins Hospital. After giving their appropriate preoperative informed consent, patients were randomly assigned to pancreaticogastrostomy or pancreaticojejunostomy after completion of the pancreaticoduodenal resection. All pancreatic anastomoses were performed in two layers without pancreatic duct stents and with closed suction drainage. Pancreatic fistula was defined as drainage of greater than 50 mL of amylase-rich fluid on or after postoperative day 10. Results: The pancreaticogastrostomy (n=73) and pancreaticojejunostomy (n=72) groups were comparable with regard to multiple parameters, including demographics, medical history, preoperative laboratory values, and intraoperative factors, such as operative time, blood transfusions, pancreatic texture, length of pancreatic remnant mobilized, and pancreatic duct diameter. The overall incidence of pancreatic fistula after pancreaticoduodenectomy was 11.7% (171145). The incidence of pancreatic fistula was similar for the pancreaticogastrostomy (12.3%) and pancreaticojejunostomy (11.1%) groups. Pancreatisc fistula was associated with a significant prolongation of postoperative hospital stay (36±5 vs. 15±1 days) (p<0.001). Factors significantly increasing the risk of pancreatic fistula by univariate logistic regression analysis included ampullary or duodenal disease, soft pancreatic texture, longer operative time, greater intraoperative red blood cell transfusions, and lower surgical volume (p<0.05). A multivariate logistic regression analysis revealed the factors most highly associated with pancreatic fistula to be lower surgical volume and ampullary or duodenal disease in the resected specimen. Conclusions: Pancreatic fistula is a common complication after pancreaticoduodenectomy, with an incidence most strongly associated with surgical volume and underlying disease. These data do not support the hypothesis that pancreaticogastrostomy is safer than pancreaticojejunostomy or is associated with a lower incidence of pancreatic fistula.
Fluorochemical Mass Flows in a Municipal Wastewater Treatment Facility

Fluorochemicals have widespread applications and are released into municipal wastewater treatment plants via domestic wastewater. A field study was conducted at a full-scale municipal wastewater treatment plant to determine the mass flows of selected fluorochemicals. Flow-proportional, 24 h samples of raw influent, primary effluent, trickling filter effluent, secondary effluent, and final effluent and grab samples of primary, thickened, activated, and anaerobically digested sludge were collected over 10 days and analyzed by liquid chromatography electrospray-ionization tandem mass spectrometry. Significant decreases in the mass flows of perfluorohexane sulfonate and perfluorodecanoate occurred during trickling filtration and primary clarification, while activated sludge treatment decreased the mass flow of perfluorohexanoate. Mass flows of the 6:2 fluorotelomer sulfonate and perfluorooctanoate were unchanged as a result of wastewater treatment, which indicates that conventional wastewater treatment is not...
Ammoxidation of propane to acrylonitrile over silica-supported Fe-Bi nanocatalysts

Abstract Ammoxidation of propane to acrylonitrile was examined over a Fe3BiOx/SiO2 sample prepared by thermal decarbonylation of [Et4N][Fe3(CO)10(μ3-Bi)] on the surface of mesoporous silica. Catalytic measurements performed at 500 °C showed that this sample yields 49% acrylonitrile selectivity at 36% propane conversion when a 5.5%C3H8/30%O2/11%NH3/He balance reaction mixture was used at a GHSV of 1360 h−1. HRSTEM, EDS, and XPS measurements indicate that mixed Fe3BiO6 oxide particles less than 2 nm in size were formed on the surface of this material under reaction conditions. A Fe/Bi atomic ratio in these particles is approximately 3:1 and the Fe and Bi ions both are in the +3 oxidation state. A Fe-Bi/SiO2 sample prepared by co-impregnation of individual Fe and Bi salts had very low activity and low selectivity for acrylonitrile formation from propane under similar experimental conditions due to larger sizes of particles formed under reaction conditions and enrichment of their surface with Fe.
Operator quantum error-correcting subsystems for self-correcting quantum memories

The most general method for encoding quantum information is not to encode the information into a subspace of a Hilbert space, but to encode information into a subsystem of a Hilbert space. Recently this notion has led to a more general notion of quantum error correction known as operator quantum error correction. In standard quantum error-correcting codes, one requires the ability to apply a procedure which exactly reverses on the error-correcting subspace any correctable error. In contrast, for operator error-correcting subsystems, the correction procedure need not undo the error which has occurred, but instead one must perform corrections only modulo the subsystem structure. This does not lead to codes which differ from subspace codes, but does lead to recovery routines which explicitly make use of the subsystem structure. Here we present two examples of such operator error-correcting subsystems. These examples are motivated by simple spatially local Hamiltonians on square and cubic lattices. In three dimensions we provide evidence, in the form a simple mean field theory, that our Hamiltonian gives rise to a system which is self-correcting. Such a system will be a natural high-temperature quantum memory, robust to noise without external intervening quantum error-correction procedures.
GumPack: A Personal Health Assistant with Reconfigurable Surface Components

Wearable and everyday-carry medical devices can improve quality of life for individuals that need frequent health monitoring. Such tools can supplement ubiquitous home care environments populated with medical sensors, extending the reach of these environments and increasing the freedom of their occupants. This paper presents the concept design for an everyday-carry medical device called a ‘GumPack’: a small cuboid-shaped device that offers wireless connectivity and plug-and-play surface components, where a component can be a biomedical sensor or a wireless network coordinator that manages a body area network. This geometrical layout optimizes access to surface-based medical hardware mounted on a small form factor. The device offers substantive computing power, supports local component reconfigurability, and promotes interoperability with medical device coordination environments. The GumPack is envisioned to be a personal health assistant carried in a pocket or handbag that can operate alone or interface to, e.g., a cell phone.
NMR measurement of the nuclear shielding isotope shift in molecular hydrogen

Measurements have been made of the isotope shift sigma(D/sub 2/)-sigma(HD) over the temperature range 18 to 296 K in the density range 10 to 850 amagats (one amagat is density at STP). At 296 K in the zero-density limit our value for the shift is 0.0469 +- 0.0005 ppm, an improvement by nearly two orders of magnitude over the existing uncertainty. The predicted but previously unobserved temperature dependence has been found. A density dependence has also been observed.
Design, simulation, and characterization of THz metamaterial absorber

In recent years a great amount of research has been focused on metamaterials, initially for fabrication of left-handed materials for use in devices such as superlenses or electromagnetic cloaking. Such devices have been developed and demonstrated in regimes from the radio frequency all the way to infrared and near optical frequencies. More recently, it has been shown that, by careful adjustment of the effective permittivity and permeability, near perfect electromagnetic absorbers can be realized. High absorption occurs when transmission and reflection are simultaneously minimized. With some clever tuning of the electric and magnetic responses, the electric and magnetic energy can therefore both be absorbed by the same metamaterial structure. In this work we present the design, simulation and characterization of a novel thin, flexible, polarization insensitive metamaterial absorber. Finite-element simulation results show that this device achieves almost perfect absorption at THz frequencies. Each unit cell of the absorber is made up of two metallic structures separated by a dielectric filler material. The electric response can be tuned by adjusting the geometry of the top metallic electric ring resonator structure. We demonstrate that a rotation about the axis of THz wave propagation at normal incidence does not change the absorption or the resonance frequency by a significant amount. A value of absorption of 99.6 % at a resonance frequency of 0.84 THz can be achieved. We also demonstrate the characteristics of this absorber structure under various THz wave incidence angles, with respect to both the incident electric and magnetic fields.
Learning and Memory: While You Rest, Your Brain Keeps Working

A recent study shows that brain activity recorded while the human subject is at 'rest' is significantly affected by a prior learning episode. These results suggest that understanding resting brain activity may be critical to understanding how humans learn from experience.
Structural Panel VARs

The paper proposes a structural approach to VAR analysis in panels, which takes into account responses to both idiosyncratic and common structural shocks, while permitting full cross member heterogeneity of the response dynamics. In the context of this structural approach, estimation of the loading matrices for the decomposition into idiosyncratic versus common shocks is straightforward and transparent. The method appears to do remarkably well at uncovering the properties of the sample distribution of the underlying structural dynamics, even when the panels are relatively short, as illustrated in Monte Carlo simulations. Finally, these simulations also illustrate that the SVAR panel method can be used to improve inference, not only for properties of the sample distribution, but also for dynamics of individual members of the panel that lack adequate data for a conventional time series SVAR analysis. This is accomplished by using fitted cross sectional regressions of the sample of estimated panel responses to correlated static measures, and using these to interpolate the member-specific dynamics.
Anisotropy of magnetic susceptibility in welded tuffs: application to a welded-tuff dyke in the tertiary Trans-Pecos Texas volcanic province, USA

Consideration of published anisotropy of magnetic susceptibility (AMS) studies on welded ignimbrites suggests that AMS fabrics are controlled by groundmass microlites distributed within the existing tuff fabric, the sum result of directional fabrics imposed by primary flow lineation, welding, and (if relevant) rheomorphism. AMS is a more sensitive indicator of fabric elements within welded tuffs than conventional methods, and usually yields primary flow azimuth estimates. Detailed study of a single densely welded tuff sample demonstrates that the overall AMS fabric is insensitive to the relative abundances of fiamme, matrix and lithics within individual drilled cores. AMS determinations on a welded-tuff dyke occurring in a choked vent in the Trans-Pecos Texas volcanic field reveals a consistent fabric with a prolate element imbricated with respect to one wall of the dyke, while total magnetic susceptibility and density exhibit axially symmetric variations across the dyke width. The dyke is interpreted to have formed as a result of agglutination of the erupting mixture on a portion of the conduit wall as it failed and slid into the conduit, followed by residual squeezing between the failed block and in situ wallrock. Irrespective of the precise mechanism, widespread occurrence of both welded-tuff dykes and point-welded, aggregate pumices in pyroclastic deposits may imply that lining of conduit walls by agglutionation during explosive volcanic eruptions is a common process.
Some puzzles of international society

(1997). Some puzzles of international society. Cambridge Review of International Affairs: Vol. 10, No. 2, pp. 23-39.
Synthesis and characterization of isomeric cis- and trans-pyrrone model compounds.

Isomeric cis- and trans-imidazopyrrolones, obtained from the reaction of pyromellitic di-anhydride and o-phenylenediamine, were prepared as models for pyrrone polymers. The characterization of these model compounds, which represent the repeat unit of the completely cyclized polymer, provided information which could not be obtained by studying the polymer itself. Isomerism was proven by the nuclear magnetic resonance spectra of soluble ester-benzimidazole derivatives. This study indicated that a single band around 1755 cm−1 should appear in the infrared spectrum of the completely cyclized polymer. The high melting points of the model imidazopyrrolones indicate the extreme thermal stability to be anticipated from perfectly formed pyrrone polymers.
Alignment Maps of Tissues: II. Fast Harmonic Analysis for Imaging

A methodology for generating polarized light retardation and alignment direction images is presented. A rotated quarter-wave plate changes the linear polarized light to a polarized probe with various degrees of ellipticity by which samples are imaged with the use of a circular analyzer. A harmonic representation of image intensity allows simple analysis, requiring only simple image operations and realizing four orders-of-magnitude computational savings for strongly aligned tissues, where linear birefringence is the dominant optical property. The method is demonstrated for a porcine heart valve leaflet.
Prediction of the pulsation frequency of flames formed over a semi-infinite horizontal surface

Abstract The pulsation frequency of horizontally situated semi-infinite reacting surfaces is studied using linear stability theory. The analysis considers the flow to consist of an initially laminar base flow and a periodic disturbance. The governing equations are cast into a self-similar form analogous to previous analyses of boundary layers. The base flow is analyzed in terms of a flame sheet approximation, the solution to which is required to solve the disturbed flow. Some boundary conditions pertaining to the disturbances are evident but some others are inferred herein. The governing equations are solved for a flame burning n-heptane, and the results of the analysis relate the disturbance frequency of the flame to a Grashof type number which, in turn, is related to the length of the thermal boundary layer. It is determined that the frequency scales according to a power law expressed as (length)0.8.
Impact of Varying Planting Dates and Irrigation Regimes on Cotton Growth and Lint Yield Production

Yield enhancements can be obtained in the Mississippi Delta by planting irrigated cotton (Gossypium hirsutum L.) during the first week of April rather than the first week of May. Because some late season drought stress is avoided, early planting might also work for dryland production. Objectives were to compare the performance of early and normal planted cotton while grown under both irrigated and dryland conditions. Six cotton cultivars were planted in the field at Stoneville, MS during either the first week of April (Early) or the first week of May (Normal) in 2005 to 2008. Half the plots were irrigated and half were dryland. Dry matter partitioning, light interception, flowering, lint yield, yield components, and fiber quality data were collected. With the exception of the hurricane-plagued season of 2005, irrigation increased lint yield regardless of planting date. In 2006 and 2007, early planting increased lint yield by 13% under irrigated conditions, but not dryland conditions. Early planting decreased dryland lint yield by 35% in 2008 but not under irrigated conditions. Fiber from normal planted cotton was 5% stronger than from those early planted. Both early planting and dryland conditions had a propensity to increase the short fiber content. Based on the 4 yr of this research, early planting appears to need irrigation to achieve its yield benefits, which implies that dryland Mississippi Delta cotton producers should not adopt an early planting production strategy.
TEXTURE OF CARROTS.

Shear and compression strengths of individual carrots were measured with the Instron Universal Testing Machine. Compression correlated highly, but shear poorly, with sensory hardness as judged by compressing and flexing. The study confirmed the usefullness of the coefficient of compression in predicting textural quality of carrots.
Two-phase ultraviolet spectrophotometry of the pulsating white dwarf ZZ Piscium

Spectra of the pulsating white dwarf ZZ Psc (= G29-38) were obtained using the International Ultraviolet Explorer. By using a multiple-exposure technique in conjunction with simultaneous ground-based exposure-metering photometry, it was possible to obtain mean on-pulse and off-pulse spectra in the 1950-1310 A wavelength range. The ratio of the time-averaged on-pulse to off-pulse spectra is best fitted by a temperature variation that is in phase with the optical light variation. This result is consistent with the hypothesis that the observed variation is due to a high-order nonradial pulsation. Conventional ultraviolet spectra of ZZ Psc showed broad absorption features at 1390 and 1600 A. These features are also found in the spectra of the cool DA-type white dwarfs G226-29 and G67-23, and appear to increase in strength with decreasing temperature. A possible explanation for the 1600 A feature is absorption by the satellite band of resonance-broadened hydrogen Ly-alpha. Such absorption would also help explain a discrepancy between the observed pulsation amplitude shortward of 1650 A and the predicted amplitudes based on model atmospheres.
The Myth of Location Privacy in the United States: Surveyed Attitude Versus Current Practices

In the United States, legal steps have been taken to protect personal privacy, which is viewed as an individual's fundamental right. Location privacy (i.e., protection of personal and location information), however, has not received equal attention in the legal system. Given the recent popularity of location-based services (e.g., cell phones), it is possible to obtain an individual's location information easily and precisely. An investigation of public perception of privacy in the United States indicated that survey responders (1) were unaware of legal implications of location privacy violation and (2) believed that there should be location privacy protection similar to that provided by the Health Insurance Portability and Accountability Act and the Family Educational Rights and Privacy Act.
A neural model of visually-guided navigation in a cluttered world

Visually guided navigation through a cluttered natural scene is a challenging problem that animals and humans accomplish with ease. A neural model proposes how primates use motion information to segment objects and determine heading for purposes of goal approach and obstacle avoidance in response to video inputs from real and virtual environments. The model produces trajectories similar to those of human navigators by use of computationally complementary processes in its analogs of cortical areas MT−/MSTv and MT+/MSTd to determine object motion for tracking and self-motion for navigation, respectively. The model retina responds to transients in the input stream. Model V1 generates a local speed and direction estimate that is ambiguous due to the neural aperture problem. Model MT+ interacts with MSTd via an attentive feedback loop to compute accurate heading estimates in MSTd that quantitatively simulate properties of human heading estimation data. Model MT− interacts with MSTv via an attentive feedback loop to compute estimates of speed, direction and position of moving objects. This object information is combined with heading information to produce steering decisions wherein goals behave like attractors and obstacles behave like repellers. These steering decisions lead to navigational trajectories that closely match human performance.
The constructivist brain

How do the representations underlying cognitive skills emerge? It is becoming increasingly apparent that answering this question requires integration of neural, cognitive and computational perspectives. Results from this integrative approach resonate with Piaget's central constructivist themes, thus converging on a 'neural constructivist' approach to development, which itself rests on two major research developments. First, accumulating neural evidence for developmental plasticity makes nativist proposals increasingly untenable. Instead, the evidence suggests that cortical development involves the progressive elaboration of neural circuits in which experience-dependent neural growth mechanisms act alongside intrinsic developmental processes to construct the representations underlying mature skills. Second, new research involving constructivist neural networks is elucidating the dynamic interaction between environmentally derived neural activity and developmental mechanisms. Recent neurodevelopmental studies further accord with Piaget's themes, supporting the view of human cortical development as a protracted period of hierarchical-representation construction. Combining constructive growth algorithms with the hierarchical construction of cortical regions suggests that cortical development involves a cascade of increasingly complex representations. Thus, protracted cortical development, while occurring at the expense of increased vulnerability and parental investment, appears to be a powerful and flexible strategy for constructing the representations underlying cognition.
Effects of LMS, self‐efficacy, and self‐regulated learning on LMS effectiveness in business education

Purpose – The majority of e‐learning empirical research studies have focused on the two research streams: outcome comparison studies with classroom‐based learning and studies examining potential predictors of e‐learning success. The determinants of e‐learning success include interactions, instructor support and mentoring, information delivery technology, course content, self‐motivation, learning styles, and course structure. Most of these empirical studies failed to include the technological dimension as an antecedent of effectiveness of e‐learning systems. The purpose of this paper is to empirically test the effects of e‐learning management systems (LMS), self‐efficacy and self‐regulated learning on learner satisfaction and system effectiveness.Design/methodology/approach – This research model is an extension of the information systems success model of DeLone and McLean and the virtual learning environment effectiveness model of Piccoli et al. The research model was tested using the structural equation m...
Building an Eco-Innovation Cluster: Water Cluster in the Brazilian Amazon Region

This paper discusses the creation of an innovation water cluster in the Brazilian Amazon region, capitalizing in the regionâ€™s unique global competitive advantage in the development of a water innovation economy. The existence of academic institutions, research agencies, a manufacturing park, and unique natural resources offer the right environment for the creation of this water eco-innovation cluster in the city of Manaus. The development of an innovation economy in the city of Manaus in the Amazon will promote a new cycle of economic development in the region, and induce a new cycle of attraction of environmental technology companies to the Amazon region of Brazil. In addition, it will also address social objectives of the Amazon region, increasing social-economic welfare and promoting eco-competitiveness as a cornerstone of the nationâ€™s economy. This paper outlines a link between cluster theory and a water diamond model with sustainability as its major goal.
Ophthalmic manifestations of perineural spread of facial skin malignancy.

Facial skin malignancy, when complicated by perineural spread (PNS), can lead to devastating orbital, intracranial and paranasal sinus involvement, the management of which requires a multidiscipli-nary approach and which itself may be devastating. Adequate surgical excision with frozen section control, and specific inspection of histological specimens for perineural invasion, are essential to avoid this problem. This report presents four patients who manifested such involvement, and emphasises the importance of recognition of such ominous symptoms as facial pain, paraesthesiae and weakness. Thorough neuro-ophthalmic examination is mandatory to detect signs of nerve involvement which may indicate perineural spread both at the initial assessment of primary tumour and at suspected recurrence. In this series, the most common sensory and motor nerves affected were, respectively, single, small branches of the ophthalmic and facial nerves.
Faisceaux\bar{\partial}-cohérents sur les variétés complexes

Dans ce travail nous generalisons au contexte des faisceaux analytiques coherents un resultat classique de Koszul–Malgrange (Koszul and Malgrange in Arch Math 9 : 102–109, 1958) concernant l’integrabilite des connexions de type (0,1) sur un fibre vectoriel complexe C∞ au-dessus d’une variete complexe. En introduisant la notion de faisceau \(\bar{\partial}\)-coherent, qui est une notion qui vit dans le contexte C∞, nous montrons l’existence d’une equivalence (exacte) entre la categorie des faisceaux analytiques coherents et la categorie des faisceaux \(\bar{\partial}\)-coherents. Une application de notre caracterisation est une methode (la \(\bar{\partial}\)-stabilite) qui permet de trouver des structures analytiques par deformation C∞ d’autres structures analytiques.
Electro-optics and second-harmonic generation of nonlinear optical polymers

The behavior of the polar orientational order parameter of two nonlinear optical (NLO) polymers is investigated using the second harmonic generation (SHG) and the refractive index/waveguide apparatus. The two NLO systems consist of a MNA/PMMA guest/host and a BCSC according main chain polymer. The MNA/PMMA results show the inadequacy of the independent dipole orientation model for the description of the electric field poling. The BCSC system illustrates the birefringence in the refractive index is not a necessary criterion for the second order nonlinear effect such as SHG.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Molecular dynamics simulation study of the structural characteristics of water molecules confined in functionalized carbon nanotubes.

Molecular dynamics (MD) simulations were performed to study the structural properties of water molecules confined in functionalized carbon nanotubes (CNTs). Four CNTs, two armchair-type (6, 6), (7, 7) and two zigzag-type (10, 0), (12, 0) CNTs, representing different helicities and different diameters, were chosen and functionalized at their open ends by the hydrophilic −COOH and the hydrophobic −CH3 groups. The structural properties of water molecules inside the functionalized CNTs, including the orientation distributions of dipole moment and O−H bonds, the length of the single-file water chain, and the average number of hydrogen bonds, were analyzed during a process of simulations. MD simulation results in this work showed that the −CH3 functional groups exert little special effects on the structural properties of water molecules. It is mainly due to the relatively small size of the −CH3 group and its hydrophobic nature, which is consistent with hydrophobic CNTs. For CNTs functionalized by −COOH groups, ...
Education's Role in Explaining Diabetic Health Investment Differentials

Abstract This paper studies the relationship between education and diabetic health investment. The empirical work focuses on how education affects heath investment proxies such as smoking propensities, blood sugar control and diet. Increased education has a positive impact on diabetic health investment, even after controlling for IQ and available information, but the health investments of diabetics are less responsive to increases in education than are those of non-diabetics. [JEL I12, I20]
Spatial Configuration and Composition of Charge Modulates Transport into a Mucin Hydrogel Barrier

The mucus barrier is selectively permeable to a wide variety of molecules, proteins, and cells, and establishes gradients of these particulates to influence the uptake of nutrients, the defense against pathogens, and the delivery of drugs. Despite its importance for health and disease, the criteria that govern transport through the mucus barrier are largely unknown. Studies with uniformly functionalized nanoparticles have provided critical information about the relevance of particle size and net charge for mucus transport. However, these particles lack the detailed spatial arrangements of charge found in natural mucus-interacting substrates, such as certain viruses, which may have important consequences for transport through the mucus barrier. Using a novel, to our knowledge, microfluidic design that enables us to measure real-time transport gradients inside a hydrogel of mucins, the gel-forming glycoprotein component of mucus, we show that two peptides with the same net charge, but different charge arrangements, exhibit fundamentally different transport behaviors. Specifically, we show that certain configurations of positive and negative charges result in enhanced uptake into a mucin barrier, a remarkable effect that is not observed with either charge alone. Moreover, we show that the ionic strength within the mucin barrier strongly influences transport specificity, and that this effect depends on the detailed spatial arrangement of charge. These findings suggest that spatial charge distribution is a critical parameter to modulate transport through mucin-based barriers, and have concrete implications for the prediction of mucosal passage, and the design of drug delivery vehicles with tunable transport properties.
Atmosphere and agriculture in the new millennium

Abstract Effects of changing climate (CO 2 , O 3 , aerosols, UV-B radiation, temperature and precipitation) on crops are predominantly based on univariate studies. Limited bivariate studies suggest rising CO 2 levels would be beneficial to crops but may be offset by adverse O 3 effects. Elevated UV-B and ambient crop yields are difficult to project due also to limited research. Climate warming concerns, using average daily temperatures may be less important than the effects of rising nocturnal temperatures on crop growth. Traditional approaches of examining air pollutant-induced visible foliar injury or the effects of single air pollutants on crop productivity need to be redirected to the analysis of integrated holistic systems. In that context, present and future agriculture in India and the USA are compared.
Emerging roles of astrocytes in neural circuit development

Astrocytes are now emerging as key participants in many aspects of brain development, function and disease. In particular, new evidence shows that astrocytes powerfully control the formation, maturation, function and elimination of synapses through various secreted and contact-mediated signals. Astrocytes are also increasingly being implicated in the pathophysiology of many psychiatric and neurological disorders that result from synaptic defects. A better understanding of how astrocytes regulate neural circuit development and function in the healthy and diseased brain might lead to the development of therapeutic agents to treat these diseases.
ENZYMATIC METHODS FOR THE DETERMINATION OF TRITIUM AT C-1 OF D-MANNOSE AND AT C-3 AND C-5 OF D-FRUCTOSE, D-GLUCOSE, D-MANNOSE, AND THEIR 6-PHOSPHATE ESTERS

Abstract Methods have been devised for determining the distribution of carbon-bound tritium at C-1 of d -mannose and at C-3 and C-5 of d -glucose, d -fructose, d -mannose, and their 6-phosphate esters using enzymes which, in each case, catalyze the release of tritium into the solvent water, which can be isolated by distillation, and the isotopic content accurately determined. Tritium at C-1 of d -mannose is determined by reaction with glucose oxidase. The remaining positions are determined via glycolytic enzymes, with triosephosphate isomerase being used for determinging the tritium content at both C-3 and C-5 of both aldoses and d -fructose. The methods involve commercially available enzymes which, in solution, are reasonably stable and minimal chromatographic separation of intermediates. When tested using d -[3-3H]glucose and d -[5-3H]glucose, these methods gave near quantitative results.
AlGaN-Based Microwave Transmit and Receive Modules

AlGaN High Electron Mobility Transistors (HEMTs) have made great progress for solid state power amplifiers with the demonstration of an X-band power density up to 9.8 W/mm. This high power density is the result of the high current and voltage capability of this material system. Recently, it has also been shown that these devices can achieve low microwave added noise figures (NF = 0.6 dB at 10 GHz) while maintaining a large breakdown voltage (>60 V) and hence a large dynamic range. These results imply that AlGaN HEMTs can be used to perform the active transmit and receive functions in more robust, higher dynamic range modules. In this paper, the progress in AlGaN microwave HEMTs is reviewed and the issues related to AlGaN transmit and receive (T/R) modules are described.
Adult Attachment as a Framework for Understanding Mental Health and American Indian Families: A Study of Three Family Cases

This article discusses three cases of American Indian families who presented for therapy at an urban mental health center. The framework of adult attachment is used to understand the cross-generati...