cssi/SciSciGPT-SciSciNet huggingface dataset:
Building an International Soil Science

In the late 1800s, several terms described the study of soil, including agrology, agrogeology, agricultural chemistry, and pedology. The term soil science was not used until the early 1900s and became more widely used after the journal Soil Science was established in 1916. In 1908, Peter Treitz from Hungary and Gheorghe Murgoci from Romania traveled to southern Russia to participate in a soil excursion led by Konstantin Glinka. During the excursion, they hatched the idea of bringing together researchers from various countries to present methods and Approaches and seek standardization. The First International Conference of Agrogeology was organized in Budapest in 1909. Several meetings were held after that but the First World War halted progress in the foundation of an international soil science community. The Fourth International Conference of Pedology was held in Rome in 1924 and brought together 300 soil researchers and was the largest soil conference to date. On the last day of the conference, the International Society of Soil Science was established, and six commissions were formed. It was agreed that the First International Congress of Soil Science was to be held in the USA in 1927, and Jacob Lipman was elected as President.
Disparities in physical activity resource availability in six US regions.

Abstract Objective We conducted an ecological study to determine physical activity resource availability overall and by sociodemographic groups in parts of six states (CA, IL, MD, MN, NC, NY). Methods Data on parks and recreational facilities were collected from 3 sources in 2009–2012. Three measures characterized park and recreational facility availability at the census tract level: presence of ≥1 resource, number of resources, and resource kernel density. Associations between resource availability and census tract characteristics (predominant racial/ethnic group, median income, and proportion of children and older adults) were estimated using linear, binomial, and zero-inflated negative binomial regression in 2014. Pooled and stratified analyses were conducted. Results The study included 7139 census tracts, comprising 9.5% of the 2010 US population. Overall the availability of parks and recreational facilities was lower in predominantly minority relative to non-Hispanic white census tracts. Low-income census tracts and those with a higher proportion of children had an equal or greater availability of park resources but fewer recreational facilities. Stratification revealed substantial variation in resource availability by site. Conclusion The availability of physical activity resources varied by sociodemographic characteristics and across regions. Improved knowledge of resource distribution can inform strategies to provide equitable access to parks and recreational facilities.
Effect of castration on weight gain of beef calves.

Many management practices can be utilized to maximize weight and increase value of calves at weaning. Combining the two management practices of castration and implanting male calves allows producers to maximize weaning weights and avoid discounts for intact males. Crossbred bull calves were randomly assigned at birth to 1 of 3 treatment groups: castrated (n = 22), banded (n = 18) or left intact (n = 20). Calves that were castrated or banded within 24 h after birth received a zeranol implant at that time. Calves in the intact group were castrated at 150 days of age and then implanted, and the calves in the other 2 treatment groups were re-implanted at that time. There were no differences in weaning weight, average daily gain (ADG) or weight per day of age between the 3 treatment groups. Castrating calves shortly after birth reduced stress on the animal compared to castration at a older age (day 150 to weaning). Also, early castration may be more acceptable as an animal welfare issue. It is concluded that combining castration and implanting allows producers to maximize weaning weight of calves as well as reduce the stress of castration at an older age.
An efficient frequency scaling approach for energy-aware embedded real-time systems

The management of energy consumption in battery-operated embedded and pervasive systems is increasingly important in order to extend battery lifetime or to increase the number of applications that can use the system's resources. Dynamic voltage and frequency scaling (DVFS) has been introduced to trade off system performance with energy consumption. For real-time applications, systems supporting DVFS have to balance the achieved energy savings with the deadline constraints of applications. Previous work has used periodic evaluation of an application's progress (e.g., with periodic checkpoints inserted into application code at compile time) to decide if and how much to adjust the frequency or voltage. Our approach builds on this prior work and addresses the overheads associated with these solutions by replacing periodic checkpoints with iterative checkpoint computations based on predicted best-, average-, and worst-case execution times of real-time applications (e.g., obtained through compile-time analysis or profiling).
Monetary Policy in Emerging Markets

Abstract The characteristics that distinguish most developing countries, compared to large industrialized countries, include: greater exposure to supply shocks in general and trade volatility in particular, procyclicality of both domestic fiscal policy and international finance, lower credibility with respect to both price stability and default risk, and other imperfect institutions. These characteristics warrant appropriate models. Models of dynamic inconsistency in monetary policy and the need for central bank independence and commitment to nominal targets apply even more strongly to developing countries. But because most developing countries are price-takers on world markets, the small open economy model, with nontraded goods, is often more useful than the two-country two-good model. Contractionary effects of devaluation are also far more important for developing countries, particularly the balance sheet effects that arise from currency mismatch. The exchange rate was the favored nominal anchor for monetary policy in inflation stabilizations of the late 1980s and early 1990s. After the currency crises of 1994–2001, the conventional wisdom anointed inflation targeting as the preferred monetary regime in place of exchange rate targets. But events associated with the global crisis of 2007–2009 have revealed limitations to the choice of CPI for the role of price index. The participation of emerging markets in global finance is a major reason why they have by now earned their own large body of research, but it also means that they remain highly prone to problems of asymmetric information, illiquidity, default risk, moral hazard and imperfect institutions. Many of the models designed to fit emerging market countries were built around such financial market imperfections, and few economists thought this inappropriate. With the global crisis of 2007–2009, the tables have turned: economists should now consider drawing on the models of emerging market crises to try to understand the unexpected imperfections and failures of advanced-country financial markets.
Radiation of conformal slot arrays on perfectly conducting super-spheroid

Conformal slot array antennas have been widely used and intensively investigated in the past decades. As the radiation characteristics of the conformal arrays are quite dependent on the curvature of the surface on which the slots are cut, the analysis of the radiation fields is a boundary value problem and usually very involved. In this paper, an efficient technique is provided for the analysis of conformal slot arrays on super-spheroid. The radiation fields of the conformal array antenna are expressed in terms of a series of vector wave functions. Numerical computations are implemented for a variety of configurations of the slot arrays. The technique employed in this research can be easily extended to conformal arrays on any rotationally symmetric surface and find its wide applications in conformal antenna design.
Adeno‐associated viral vectors: depend(o)ble stability

Recombinant adeno-associated viral (rAAV) vectors can mediate the safe and long-term correction of genetic diseases in animal models following a single administration, and have been shown to persist and are safe in humans following delivery to lung, sinus, skeletal muscle, brain, and liver. The physiochemical properties of rAAV vector virions are amenable to industry-accepted manufacturing methodologies, long-term storage, and direct in vivo administration. Keywords: adeno-associated virus; gene therapy; gene transfer; AAV; transduction; integration
Distribution of actin filament lengths and their orientation measured by gel electrophoresis in capillaries.

F-actin was electrophoresed in capillary tubes filled with agarose gel. The use of capillary imparted high resistance on the gel allowing the use of high enough concentration of salts to keep F-actin polymerized, and allowed the application of high electric fields without liberating considerable amount of heat. The intensity profile of the electrophoretic band of F-actin showed a peak, which in 1% agarose in the electric field of 17.8 V cm−1 at 0° C, migrated at 3.4 cm hr−1. Microscopic observation of actin filaments extracted from different positions along the gel showed that during electrophoresis filaments distributed themselves in such a manner that the longest polymers migrated slowest and the shortest migrated fastest. Using this observation we calculated the weight and number distributions of filament lengths from corresponding experimental intensity profiles. Phalloidin-labelled F-actin oriented in the gel upon application of an electric field. F-actin showed unusual orientational response: it oriented rapidly when the field was applied, but relaxed very slowly when the field was removed. Orientation of F-actin varied within an electrophoretic band, longest polymers showing the best orientation and short oligomers and monomers not orienting at all. The degree of orientation increased with the size of the electric field. When F-actin was labelled with phalloidin before electrophoresis, it was no longer able to migrate in the gel, but the electric field oriented it in the same way as when it was labelled after the electrophoresis. These results show that the electrophoresis of F-actin in agarose fractionates it according to its length, that by using electrophoresis it is possible to rapidly obtain distribution of filament lengths, and that F-actin migrates in agarose by the process of reptation.
Characterization of [3H]muscimol binding to mouse brain membranes.

Abstract The binding of [ 3 H]muscimol {[methylene- 3 H(N)]-3-hydroxy-5-aminoethyl isoxazole} to a membrane fraction from mouse brain was studied as a possible model for the GABA recognition site of the γ-aminobutyric acid (GABA)-anionophore receptor complex. Kinetic studies showed two distinct association and dissociation rate constants, 2.3 × 10 −4 and 1.4 × 10 −5 sec −1 nM −1 for association and 1.2 × 10 −2 and 1.0 × 10 −3 sec −1 for dissociation. Equilibrium analysis (Scatchard plot) of binding data also indicated two types of sites with K D equal to 9 × 10 −9 and 70 × 10 −9 M. Detergents (0.1% Triton X-100, 0.1% Lubrol PX or 5% Tween 20) had no effect on the binding of [ 3 H]muscimol or other conformationally restricted agonists such as imidazoleacetic acid, isoguvacine, THIP (4,5,6,7-tetrahydroisoxazole [5,4-c] pyridine-2-ol), and (±)-isonipecotic acid. In contrast to this, the detergents potentiated the ability of the less conformationally restricted agonists such as GABA and β-alanine in displacing [ 3 H]muscimol. Binding of bicuculline was reduced by all of the detergent treatments.
Electrosurgery and cardiac pacemakers

There are two basic types of cardiac pacemakers: (1) Fixed-rate pacemakers stimulate the heart at a regular rate independent of the intrinsic heart rate. (2) Demand pacemakers sense the heart's spontaneous rhythm. They are more commonly used because they are noncompetitive with the heart. There are two varieties of demand pacemakers: ventricular-inhibited and ventricular-triggered. Their responses to electrical interference are quite different. Potential pacemaker interference is a consideration with high-frequency electrosurgery. The problems with electrosurgical interference have occurred primarily with early pacemaker models. Recent improvements in electrical shielding and filtering systems have made pacemakers very resistant to outside electrical influence. Simple electrodesiccation of small lesions on relatively healthy pacemaker patients poses negligible risks. Caution is advised for marginal patients undergoing extensive electrosurgical procedures. The potential risks are further minimized by proper attention to patient history, monitoring, proper grounding, the avoidance of cutting current, and the use of proper technic.
Major H alpha flares in centers of activity with very small or no spots

Major Hα flares (importance ⪖ 2) in plages with only small or no spots constitute a rare but well observed aspect of solar activity. Information relating to 83 such flares has been assembled and studied. In the years 1956–1968 these flares represented ∼ 7% of all confirmed flares of importance ⪖ 2. In general, the flares were of unusually long duration and rose to maximum intensity slowly. A flash phase was often absent or poorly defined. In a number of cases, the flare emission included two bright filaments more or less parallel. The flares usually occurred during the late, flare-poor phase of a center of activity, and their outbreak did not presage a resurgence of activity in subsequent rotations. The flares were frequently associated with the position of dark filaments.
Physical discrimination of amine vapor mixtures using polythiophene gas sensor arrays

Abstract Sensor arrays are extremely powerful sensing platforms because the use of an array enables more discrimination power than achievable by using a single sensor. Unfortunately most current research on gas or vapor sensor arrays focuses on distinguishing between classes of molecules. For many attractive applications, such as environmental monitoring or food spoilage detection, it is important to discriminate within each class of molecule. We demonstrate simple yet powerful arrays that can discriminate vapor molecules based on their size and the molecular arrangement. Gas sensing is accomplished using polythiophene-based thin film transistors (TFTs) that respond to analyte vapors with changes in electrical behavior. By varying the side chain of the polythiophene molecule as well as adjusting the thickness of the polythiophene films, size discrimination of amine vapors can be accomplished using small arrays of polythiophene transistors. With these arrays, size discrimination is even possible with mixtures of amine vapors. Grazing incidence X-ray diffraction (GIXD) shows that the film orientation and plane spacings depend on the side chain length of the polythiophene, and these structural differences are used to explain the sensor behavior.
Climate science: A high bar for decadal forecasts of El Nino

Climate simulations suggest that multi-decadal periods of high and low variability in the phenomenon known as the El Nino-Southern Oscillation in the tropical Pacific Ocean may be entirely unpredictable.
Real-time adaptive feedback control of combustion instability

An active adaptive feedback control approach is utilized to minimize pressure fluctuations in a laboratory-scale dump combustor. Essential elements of the controller include sensors, actuators, and a control strategy. The actuation mechanism consists of spanwise forcing of the inlet boundary layer. This forcing is acoustically driven and has been shown to reduce the magnitude of the pressure oscillations by altering the dynamics of the flame-vortex interaction. The control strategy is based on the adaptive filtered-x least-mean-square (LMS) algorithm. Adaptive systems monitor their own performance and vary their internal structure to optimize this performance. The LMS algorithm does not require off-line gradient estimates to search for the minima on the performance surface, making it computationally efficient. A piezoelectric transducer measures the real-time pressure signal that is used as feedback as well as a measure of the error to train the adaptive algorithm. In its efforts to minimize the pressure fluctuations, the adaptive algorithm updates the weights of a digital filter, in real time. The digital filter, as well as the adaptive algorithm, resides on a digital signal processing (DSP) board. Both finite impulse response (FIR) and infinite impulse response (IIR) filter structures were investigated. It was found that the recursive direct-form filter structure is required to prevent the algorithm from driving itself toward instability.
Modelling of anisotropic sintering in crystalline ceramics

We present a model that describes anisotropic shrinkage during sintering in a powder compact of aligned, elongated particles by deriving the anisotropic sintering stress and the anisotropic generalized viscosity as a function of material and geometric parameters. The powder compact consists of elongated particles, which are perfectly aligned and simply packed with elliptical pores at all the quadra-junctions between the particles. The model considers mass transport by grain boundary diffusion and surface diffusion. Shrinkage rates are calculated for a variety of geometries and are compared to kinetic Monte Carlo simulations.
Comment on noise in transferred electron amplifiers

Abstract The noise in transferred electron amplifiers is usually attributed to thermal noise of the carriers in the two valleys and intervalley scattering noise. The latter is here interpreted as being due to carrier density fluctuations in the two valleys (partition noise), which, because of the difference in mobility in the upper and lower valleys, shows up as current noise.
Nanomedicine: seeing the benefits of ceria.

Cerium oxide nanoparticles can scavenge reactive molecules in the eye and prevent degenerative retinal disorders in rats. The results suggest that nanoceria particles could be used to treat a variety of problems that cause blindness.
Toward Understanding Tryptophan Fluorescence in Proteins

A general approach to dissecting the complex photophysics of tryptophan is presented and used to elucidate the effects of amino acid functional groups on tryptophan fluorescence. We have definitively identified the amino acid side chains that quench tryptophan fluorescence and delineated the respective quenching mechanisms in a simple model system. Steady-state and time-resolved fluorescence techniques, photochemical H-D exchange experiments, and transient absorption techniques were used to measure individual contributions to the total nonradiative rate for deactivation of the excited state, including intersystem crossing, solvent quenching, and excited-state proton and electron transfer rates. Eight amino acid side chains representing six functional groups quench 3-methylindole fluorescence with a 100-fold range in quenching rate constant. Lysine and tyrosine side chains quench by excited-state proton transfer; glutamine, asparagine, glutamic and aspartic acid, cysteine, and histidine side chains quench by excited-state electron transfer. These studies provide a framework for deriving detailed structural and dynamical information from tryptophan fluorescence intensity and lifetime data in peptides and proteins.
The Mitsunobu reaction in preparing 3-deazapurine carbocyclic nucleosides

The coupling reaction of 4-chloro-1H-imidazo(4,5-c)pyridine (6-chloro-3-deazapurine, 3) with several cyclopentyl derivatives under Mitsunubo reaction conditions provides an efficient entry into N-7 and N-9 substituted 3-deazapurine carbocyclic nucleosides of antiviral potential. The versatility of this procedure is illustrated with a new and efficient synthesis of (K)-3-deazaaristeromycin, a formal preparation of 3-deazaneplanocin A, and a route to 3-deaza-5 0 -homoaristeromycin.
Design and Characterization of a BioMEMS Device for In-Vitro Mechanical Stimulation of Single Adherent Cells

This paper presents development of a BioMEMS device to mechanically stimulate single adherent cells by means of electrostatic actuation. The main components of the proposed device include a platform for cell placement and an electrostatic comb drive actuator to provide in-plane motion. A high frequency actuation method was used to enable actuation in aqueous solutions. Displacements greater than 5μm were measured when the device was actuated with a 1 MHz square wave signal with 10V peak amplitude in DI water. Additionally, this device was successfully actuated in ionic solutions up to 50mM NaCl aqueous solution using frequencies greater than 30 MHz. Significant electrolysis and corrosion of the polysilicon and metal layers was observed when the devices were actuated in saline solutions with peak voltages greater than 15V, thus indicating that there is a limit on the maximum actuation voltage that can be used. No noticeable actuation was observed in phosphate buffer solution (PBS) or cell culture medium even when frequencies as high as 50 MHz were used due to ion migration. Theoretical calculations suggest that frequencies of the order of 100-500 MHz will be required for actuation in cell culture media. Currently we are in the process of building an experimental set-up to allow use of such high frequencies. Initial results for cell plating experiments on the cell stretcher platform and other considerations for device implementation are discussed in the end.Copyright © 2005 by ASME
Variational approaches toward nonlinear time-series analysis.

Linear autoregressive models (AR) have broad applications toward spectral analyses and digital filtering of signals, as well as identification, prediction, and control of dynamical systems. However, the symmetric Gaussian properties of linear AR presume independence between the first and second order moments of system outputs. Using nonlinear AR to quantify interactions between the mean and autocovariance of a signal, analysts can discriminate asymmetric frequency components, estimate the relative contribution of system nonlinearities toward mean output, evaluate relative structural stability of a system, and predict critical regions where bifurcations in its dynamics might occur. Quadratic analyses are performed on simulated outputs from a nonlinear model and various experimental time series (Canadian lynx population, respiratory volume dynamics in rat, Cheyne–Stokes respiration in patients with congestive heart failure, intracranial pressures in patient with cerebral hematoma). These case studies demonstrate the utility of the techniques for evaluating the qualitative behaviors of dynamical systems in the presence of slowly varying inputs. © 1999 Biomedical Engineering Society.
Polynomial-mappings and M-equivalence

Let R be an integral domain which is either finitely generated over its prime subring or a Noetherian domain with only finite residue fields and only finitely many units. Let f be a univariate polynomial of degree ⩾2 having coefficients in R and let E be an infinite subset of R. Then, we prove the existence of a maximal ideal m of R such that E and f(E) have distinct m-adic closures. As a corollary, we derive some results on polynomial equivalence and full-invariance of subsets under polynomial mappings.
Diffusion of fractal aggregates in the free molecular regime.

We use static and dynamic light scattering to determine how the diffusion coefficient of a fractal aggregate in the free molecular regime depends on its morphological properties. Our system is a carbonaceous flame soot aerosol containing fractal aggregates with ${\mathit{D}}_{\mathit{f}}$=1.8. We find that the Epstein equation for the diffusion coefficient holds with an effective mobility radius given by ${\mathit{R}}_{\mathit{m}}$=0.99${\mathit{aN}}^{0.43}$, where N is the number of monomers per aggregate and a is the monomer radius. This result is quantitatively explained as due to the projectional area of the aggregate which includes monomer-monomer screening.
Inorganic and Organic Hybrid Materials for Improving Thermoelectric Performance of Polymer Nanocomposites

Copper nanoparticles were incorporated with Carbon Nanotube (CNT)/polymer nanocomposites in order to enhance the thermopower by enlarging the energy gap between the Fermi level and the mean of differential electrical conductivity. The thermopower was increased as ∼ 2 times with 1 vol% of copper nanoparticles. The effects of copper concentration on the electrical and thermal properties of the composites were studied.Copyright © 2012 by ASME
Inspection of high-performance peltier coolers using lock-in thermography

Peltier cooling devices are used on the Hubble Space telescope for temperature control of various detector packages. A typical construction of these devices involves sandwiching an array of Bismuth-Tellurium (Bi2Te3) posts between two ceramic plates. When a DC current is applied to the device heat is moved from one side of the device to the other, depending on the polarity of the current. Because these devices can change temperature very rapidly, there is the potential for damage due to thermal expansion and contraction of the constituents. A failure in the bonding of the Bi2Te3 to the ceramic sheet can lead to reduced efficiency or failure of the device. NASA Langley Research Center has developed a nondestructive thermal imaging technique to determine the integrity of the Bi2Te3 posts through the ceramic surface of the peltier device. By driving the peltier device with a time varying DC current, a corresponding temperature rise and fall can be observed on the surface of the device using a commercial infrared camera. Lock-in thermography can then be used to construct both phase and amplitude images of the front surface temperature. It has been found that failure of Bi2Te3 posts results in a measurable change in both the amplitude and phase. This paper will describe an inspection method that has been developed and show results of the inspection of the extremely small Bi2Te3 posts whose dimensions are 0.81mm by 0.81mm and approximately 1.45mm tall.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Preliminary study of transurethral photodynamic therapy mediated with Tookad in a canine prostate model

Background: photodynamic therapy (PDT) mediated with vascular acting photosensitizer Tookad (pd-bacteriopheophorbide) was investigated as an alternative modality for treating prostate cancer. Our previous studies show that Tookad PDT can induce marked prostatic tissue lesion but minimal urethral lesion. In this study a transurethral procedure was used to evaluate the response of the prostatic urethra to direct urethral irradiation. Materials and Methods: Tookad solution (2.5 mg/ml) was administered (1 mg/kg) through IV catheter by an infusion pump over 10 min. A diffuser fiber (1 cm active length) was inserted into the prostatic urethra. The light irradiation (50 or 100 J/cm) started at 4 min after the onset of drug infusion. Urinalysis was performed for 24 - 48 h post PDT. One week after PDT, prostates (n = 4) were removed at necropsy and subjected to histopathological examination. Results: The cross section of prostates showed severe hemorrhagic and necrotic lesions on the right lobe. The diameter of the lesion, measured from urethra to capsule, was >13 mm for 50 J/cm treatment and >18 mm for 100 J/cm, respectively. Although underlying periurethral lesion was visible, the urethral surface was intact and prostatic urethra was open. Conclusions: The joint point of the diffuser tip and the guide fiber might be bent while passing through the sharp turn at the Ischial Arch, which could affect the light distribution and cause the asymmetric lesion. Nonetheless, the transurethral direct irradiation can induce marked prostatic tissue lesion but minimal urethral lesion.
Inflammatory macular atrophy: Immunofluorescent and ultrastructural findings

Abstract In a patient with primary inflammatory macular atrophy, immunofluorescence studies disclosed both C'3 and IgM in a granular and fibrillar pattern in the dermis between the collagen fibers and at the basement membrane zone. Localization of C'3 to autofluorescent elastic fibers was demonstrated. Ultrastructural examination showed the presence of activated macrophages enveloping fragmented elastic fibers. Immunologie mechanisms may play a participatory role in some forms of macular atrophy.
Shoot elongation retardation owing to daminozide in Chrysanthemum: II. Modeling multiple applications

A model for simulating the effect of an application of daminozide on shoot elongation of potted chrysanthemum (Dendranthema × grandiflora (Ramat.) Kitamura) shoots was adapted to simulate the effect of multiple growth retardant applications using four different approaches. The resulting simulation model allowed testing of optimal strategies for timing daminozide concentrations as well as for comparison of predictions with observed shoot growth data. Of the four approaches tested, the two which performed best were (1) the elimination approach, where the residual effect from previous applications was discarded, (2) the residual-additive approach, where the residual effect from previous applications was incorporated by computing a theoretical daminozide concentration for the residual effect and adding this to the concentration of the new application. The elimination approach appeared to be more suitable for situations where multiple applications were spaced more than 7 days apart, while the residual-additive approach was better at closely spaced applications. These two approaches predicted that two spray applications of daminozide at concentrations of 0.25% a.i. would result in maximum shoot length reductions of 19% and 23%, respectively; 22% and 30% with three applications. The optimal application dates predicted with the elimination approach were Days 16 and 34 after pinching for two applications, and Days 11, 26, and 41 for three applications.
Novel Copolymers of Vinyl Acetate and Some Ring‐Substituted 2‐Phenyl‐1,1‐dicyanoethylenes

Electrophilic trisubstituted ethylene monomers, halogen ring‐disubstituted 2‐phenyl‐1,1‐dicyanoethylenes, RC6H3CH˭C(CN)2 (where R is 2,3‐diCl, 2,4‐diCl, 2,6‐diCl, 3,4‐diCl, 3,5‐diCl, 2,4‐diF, 2,5‐diF, 2,6‐diF, 3,4‐diF, 3,5‐diF, 2‐Cl, 6‐F) were synthesized by piperidine catalyzed Knoevenagel condensation of ring‐substituted benzaldehydes and malononitrile, and characterized by CHN elemental analysis, IR, 1H‐and 13C‐NMR. Novel copolymers of the ethylenes and vinyl acetate were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C‐NMR, GPC, DSC, and TGA. High Tg of the copolymers, in comparison with that of polyvinyl acetate, indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that t...
Growth-focused or profit-focused firms: transitions toward profitable growth.

Abstract Profitable growth is the most desirable state tourism and hospitality firm managers can hope to achieve. In reality, however, it is not easy for a tourism and hospitality firm to consistently grow and accumulate profits. In order to achieve profitable growth, some firms focus on sales growth while victimizing profits, while others concentrate on profits and hold off on growth. To better understand these strategies, this study investigated the growth state, profit state and transitions of restaurant firms. The findings of this study supported that profit-focused firms are more likely to achieve profitable growth than growth-focused firms. In addition, growth-focused firms with low liquidity had a higher likelihood of transitioning to a state of low growth and low profit in the short-term, and this liquidity effect was more serious for small firms in terms of long-term performance. Further, when profit-focused firms had few growth opportunities, large free cash flows increased the likelihood of transitioning to a state of low growth and low profit in the short-term. More detailed results are provided in this paper.
Effect of dibutyryl cyclic AMP on nucleic acid and protein synthesis in neuronal and glial tumor cells.

Abstract Neuroblastoma and astrocytoma cell lines were grown in the presence of dibutyryl cyclic AMP. DNA and RNA syntheses were inhibited, but protein synthesis was stimulated. The results suggest the possible involvement of protein synthesis in the dibutyryl cyclic AMP-induced morphological differentiation of mammalian cells in culture.
Influence of salinity upon sediment-water partitioning of aromatic hydrocarbons

Concern over the potential acute and long-term effects of oil pollution on marine environments has lead to a resurgence of investigations of the fate, transport and chemical transformations of aromatic hydrocarbons associated with spilled oil, exploration and operational discharges and produced water discharges in coastal marine and estuarine environmental systems. The nature of the particle reactivity or sorption/desorption equilibria which control the fate, transport and chemical transformations of hydrocarbons has been investigated on various sediment types (a range of organic carbon and particle sizes) over a range of salinities. No significant differences were observed between sorption and desorption equilibrium constants (Kd). Significant increases in sorption/desorption constants were observed with increasing salinity. A thermodynamically-based model is presented which allows the estimation of both the Setchenow constant as well as the chemical activity coefficient of the compound in the sediment organic phase from experimental data. The results of the application of this model suggest that the increase in sorption with salinity is the result of two phenomena: salting out as the result of electrolyte effects on the aqueous activity coefficient of the solute and the salting out of the sediment organic matter resulting in changes in the charge and conformation with increasing ionic strength.
Seamless real-time content delivery in wireless cognitive radio networks

In this paper, we propose a strategy for individual users to purchase frequency spectrum in cognitive radio based wireless networks. From the user's perspective, the goal is to reduce the cost of acquiring the spectrum needed to meet the quality of service needs of their real-time streaming applications. The key aspect of our proposed strategy is that the users can purchase spectrum for use in future time instances based on stochastic predictions of their locations and the prices set by competing wireless service providers. Another important aspect of the proposed strategy is that the tuning of many design parameters is not required as the tuning is often needed in conventional schemes. To evaluate our proposed scheme, we model a user utility function based on the cost of spectrum purchase and its impact on the quality of service. Simulation results show that the proposed strategy performs better than baseline schemes in terms of user utility.
Texture analysis of fluorescence lifetime images of nuclear DNA with effect of fluorescence resonance energy transfer.

Fluorescence microscopy, lifetime imaging,and texture analysis were used to study the spatial distri-bution of ﬂuorophores bound to nuclear DNA. 3T3-Swissalbino mice ﬁbroblast nuclei were labeled with Hoechst33258 (Ho), an AT-speciﬁc dye, and 7-aminoactinomycinD (7-AAD), a GC-speciﬁc dye. Ho is a RET donor to the7-AAD acceptor.
Regulation of lymphocyte growth by antagonists of interleukin-2 or its cellular receptor

The dependence of T cell proliferation on the production, binding and utilization of the lymphokine growth factor IL-2 has fostered the development and testing of new classes of drugs which act to either inhibit IL-2 production or the interaction of IL-2 with its cellular receptor. We have reviewed evidence which documents the potent immunosuppressive effects of inhibitors of IL-2 synthesis and secretion, such as Ciclosporin A, and of anti-IL-2 receptor MAb. The similarities of the potency and specificity of these agents and their effectiveness in a wide range of clinical settings encourage further studies on their mechanism of action. Perhaps the most dramatic similarity is the induction of long-term nonresponsiveness after drug removal to antigens present at the time of drug therapy. This observation has profound importance both on clinical manipulation with these agents and n the origins and maintenance of self-tolerance.
Effect of Thermal Properties on Heat Transfer in Cryopreservation and Cryosurgery

Biological materials in both cryopreservation and cryosurgery are composed of various chemicals and experience a wide range of temperature change. Therefore, their thermal properties including specific heat, latent heat (including water/ice and eutectic phase change) and thermal conductivity are expected to change significantly during freezing/thawing. The effects of thermal properties on heat transfer in cryopreservation/cryosurgery were studied experimentally and numerically. Thermal properties of various biological aqueous solutions were measured over a wide temperature range (−150~30°C). To estimate the effect of thermal property changes on the heat transfer, numerical simulations of both cryopreservation (cooled from outside) and cryosurgery (cooled from inside) geometries were performed with constant and temperature-dependent properties. The results show that the constant-property case significantly under-predicts the heat transfer over the temperature-dependent-property case regardless of the geometry.Copyright © 2002 by ASME
Exact solutions of piezoelectric materials with moving screw and edge dislocations

Abstract The authors in this paper obtain the exact solutions of moving screw and edge dislocations for a hexagonal piezoelectric material by using the eigenstrain theory, which is widely used for elastic materials. From these solutions, one can obtain many meaningful insights of coupling characteristics between mechanical and electric fields for piezoelectric materials. The results show that the decoupled theory, which neglects piezoelectric constants, yields large errors for the mechanical displacement and the electric potential in the piezoelectric material. In addition, the displacement distribution can be obtained exactly by measuring the electric potential distribution. Moreover, the displacement can be totally controlled by applying a certain external electric potential. All these properties are shown by three frequently used piezoelectric materials PZT-4, ZnO, and CdS.
Comment on "Water Tunnel Flow Visualization: Insight into Complex Three-Dimensional Flow Fields"

T are two comments which need to be made with regard to the subject paper (Ref. 1). The first is that extreme care must be exercised in establishing vortex breakdown from inflections in the lift curve slope for strakewing configurations. This can be illustrated by the fact that when the vortex lift theory solutions incorporating all of the trigonometric terms (Polhamus' Suction Analogy—Ref. 2) are used, there is a naturally occurring inflection in the lift curve, i.e., a reduction in the lift curve slope, commencing about a= 16 deg (Ref. 3) and it is unassociated with vortex breakdown. The second comment is that regarding the correlation of wind tunnel force data with water tunnel flow photographs, it must be kept in mind that discrepancies do exist between the vortex breakdown angles observed on strake-wing configurations in the wind tunnel and low Reynolds number water tunnel. (See Ref. 4, for example.) So although the water tunnel appears to provide useful qualitative configuration effect information, it may be questioned from a quantitative standpoint. In view of the preceding comments, one should use extreme caution in applying the vortex breakdown analysis method outlined in the subject paper to strake-wing configurations.
Some observations on the stained blood cellular elements of channel catfish, Ictalurus punctatus

Slides were prepared from blood of channel catfish, Ictalurus punctatus, and evaluated. The cellular blood elements observed were thrombocytes, lymphocytes, neutrophils, monocytes, eosinophils, basophils, granular anucleate bodies, erythrocytes. In channel catfish, thrombocytes, lymphocytes and neutrophils were the predominate leucocytes. Erythrocytes were observed in various stages of development. Smudge cells were observed in all smear preparations. The variations found between the observations in this study and information provided in the literature suggest the need for establishing a standardized terminology.
The developmental dialectic: Its place in clinical listening

This article explores the ongoing internal dialectic between developmental states of merger and autonomy as it unfolds in clinical practice. A review of contemporary theory and illustrative case material suggest that attending to this dialectic-both in the client and in oneself-enhances clinical listening and fosters empathic attunement.
Intrinsic neuromuscular defects in the neurogenic bladder: IX. Effects of combined parasympathetic decentralization and hypogastric neurectomy on neuromuscular ultrastructure of the feline bladder base

Previous studies have shown that unilateral decentralization of the feline bladder by sacral ventral rhizotomy results in ultrastructural neuromuscular changes in the bladder base. In the present study, the neuromuscular ultrastructure of the feline bladder base was studied in twenty sexually mature adult male cats 1–4 and 6–10 weeks following bilateral sacral rhizotomy, alone and combined with hypogastric neurectomy. The former procedure resulted in initial degeneration of cholinergic axons with loss of their neuroeffector junctions, but the adrenergic axons and neuroeffector junctions were preserved; within 6–10 weeks, the bladder base became re-innervated by regenerated cholinergic, increased adrenergic, and abundant probable copeptidergic axons. In contrast, combined sacral rhizotomy and hypogastric neurectomy resulted in persistent (up to 10 weeks) degeneration of both cholinergic and adrenergic axons with loss of their neuroeffector junctions, and no adrenergic hyperinnervation, with only a modest increase in probable copeptidergic axons in long-term samples. Our observations indicate that intact efferent sympathetic pathways are essential for eventual cholinergic re-innervation and adrenergic hyperinnervation of the decentralized bladder and suggest that the latter is an important factor in the development of vesical hypertonicity in lower-motor neuron lesions. On this basis, we introduce the concept that two functional types of the lower motor neurogenic bladder–i.e., the hypertonic with intact and the normotonic with injured efferent sympathetic pathways–may be distinguishable morphologically by ultrastructural study of the vesical muscularis.
Immortalization of hypothalamic GnRH by genetically targeted tumorigenesis

By genetically targeting tumorigenesis to specific hypothalamic neurons in transgenic mice using the promoter region of the gonadotropin-releasing hormone (GnRH) gene to express the SV40 T-antigen oncogene, we have produced neuronal tumors and developed clonal, differentiated, neurosecretory cell lines. These cells extend neurites, express the endogenous mouse GnRH mRNA, release GnRH in response to depolarization, have regulatable fast Na+ channels found in neurons, and express neuronal, but not glial, cell markers. These immortalized cells will provide an invaluable model system for study of hypothalamic neurosecretory neurons that regulate reproduction. Significantly, their derivation demonstrates the feasibility of immortalizing differentiated neurons by targeting tumorigenesis in transgenic mice to specific neurons of the CNS.
New observations on decremental atriofascicular and nodofascicular fibers: implications for catheter ablation.

Introduction: The purpose of this study was to characterize the anatomy and physiology of accessory pathways that exhibit anterograde decremental conduction. Results: Among 100 consecutive patients with an accessory pathway undergoing electrophysiological study, six individuals with decremental anterograde accessory pathway conduction were identified. Anterograde accessory pathway effective refractory periods and conduction curves were assessed by atrial extrastimulus testing. Atrial pace mapping and ventricular activation sequence mapping were used to define accessory pathway origin and insertion. Surgical ablation (N = 1) or radiofrequency catheter ablation (N = 3) was performed based on accessory pathway anatomy as determined during electrophysiological study. Four of 6 patients had gaps in anterograde accessory pathway conduction. Two patients had evidence of functional longitudinal dissociation in the accessory pathway. Five of 6 patients had atriofascicular fibers with an atrial rather than AV nodal site of origin of their decrementally conducting accessory pathway and with distal insertions in the right bundle branch. Among these five patients, a right posterior atrial origin was nearly as common as a right anterior atrial origin. One patient had a true nodofascicular fiber that arose from the AV node, inserting distally into the left bundle branch. Conclusion: Most accessory pathways with anterograde decremental conduction arise from the right anterior or right posterior atrium, not the AV node. A gap in anterograde accessory pathway conduction and functional longitudinal dissociation are common in such accessory pathways. Surgical or catheter ablation of such pathways is effective when directed at the atrial origin of the accessory pathway. True nodofascicular fibers arising from the AV node are rare. These may insert distally in the left ventricle. Catheter ablation of the proximal origin of such fibers is likely to result in complete AV block.
Evidence for very narrow shape resonances in low-energy electron-Cs scattering.

A relativistic scattering calculation based on the Dirac {ital R}-matrix method has been performed within a two-electron model-potential approach for negative-ion binding energies as well as elastic and inelastic scattering cross sections. We find multiplets of narrow shape resonances with {ital J}=0, 1, and 2, and widths of a few meV. Their {ital J}-averaged energies for even and odd parity are 119.0 meV below the 6{ital p}{sub 1/2} threshold and 9.1 meV above the 6{ital s}{sub 1/2} threshold.
Modeling effects on suicidal behavior.

Knowledge of suicidal behavior, i.e., psychiatric patients indicating that they have an acquaintance or relative who has attempted or committed suicide, has been cited as a risk factor in the assessment of suicide potential. The authors evaluated psychiatric patients hospitalized for a suicide attempt (N = 30), serious suicidal ideation (N = 26), or other non-suicide-related reasons (N = 20) and also a control group of 18 patients admitted for orthopaedic surgery. Information derived from a structured clinical interview revealed that suicide attempters have fewer suicidal models than individuals in the other patient groups, and they are more interpersonally distant from the models they do know. Depression level was not positively related to the recall and reporting of suicidal models. Measures assessing suicide-related beliefs revealed that suicide attempters rated suicide as an effective solution for problems to a greater extent that did patients in the remaining three groups. The implications of these results for social learning models of suicidal behavior are discussed.