cssi/SciSciGPT-SciSciNet huggingface dataset:
Automatic monitoring of forecast errors

This paper evaluates a variety of automatic monitoring schemes to detect biased forecast errors. Backward cumulative sum (cusum) tracking signals have been recommended in previous research to monitor exponential smoothing models. This research shows that identical performance can be had with much simpler tracking signals. The smoothed-error signal is recommended for α = 0.1, although its performance deteriorates badly as α is increased. For higher α values, the simple cusum signal is recommended. A tracking signal based on the autocorrelation in errors is recommended for forecasting models other than exponential smoothing, with one exception. If the time series has a constant variance, the backward cusum should give better results.
An exploratory study of depression among older African American users of an academic outpatient rehabilitation program.

Variation in the presentation of depressive illness among older African Americans may complicate assessment of depression, especially among those with multiple medical comorbidities and functional disabilities. The purpose of this study was to explore the prevalence of depression among older poor African Americans attending an academic outpatient rehabilitation program, using a depression measure with low somatic item content. Correlates of depression in this population also were explored. Health-care records of 150 older African Americans seen over a 2-year period were examined. Depression was assessed on admission using the 30-item Geriatric Depression Scale (GDS). Using a GDS cutoff score for depression of 11 or higher, 30% of the sample (age 75.5 ± 7.16 years, range 65–95, 75% women) scored positive for depression. Nine percent also reported having suicidal thoughts within the previous week. Consistent with existing literature, depressed patients, as compared to nondepressed patients, were significantly younger, more suicidal, more likely to rate their general health as poor, had higher mean ratings of pain, and more often limited their social activities. Six GDS items were found to have little ability to discriminate between depressed and nondepressed patients: satisfaction with life, getting bored easily, prefer staying at home, find life exciting, getting started on new projects, and full of energy. The authors recommend further testing of the GDS with similar populations of older, poor, medically ill, and functionally disabled older adults.
Dynamic Modeling and Control of Packing Pressure in Injection Molding

A dynamic model of injection molding developed from physical considerations is used to select PID gains for pressure control during the packing phase of thermo-plastic injection molding. The relative importance of various aspects of the model and values for particular physical parameters were identified experimentally. The controller gains were chosen by pole-zero cancellation and root-locus methods, resulting in good control performance. Both open and closed-loop system responses were predicted and verified, with good overall agreement.
Infrared and Raman studies of rotational correlation functions in liquids

Abstract Raman and infrared band shapes of some symmetric top molecules in the neat liquid and in solution were measured and used to obtain vibrational and rotational correlation functions and relaxation times. The results are compared with the predictions of the Debye rotational diffusion theory, the Gordon J diffusion model and the Ivanov rotational-jump model. Except for the latter theory none of these theories are consistent with both the infrared and Raman results for CD 3 I and CH 3 I.
Government competence, economic performance and endogenous election dates

Abstract Empirical research in comparative politics has largely demonstrated that favorable economic conditions improve the electoral fortunes of incumbent government parties. Thus, in parliamentary democracies in which the government can choose when to call an election there is an incentive for government parties to act strategically by calling early elections when economic conditions are favorable. Alesina, Cohen and Roubini, however, cast doubt on this proposition, finding only weak evidence of a relationship between economic factors and election timing. In this paper, we reconsider the relationship between economic conditions and endogenous election dates using new data, controlling for political factors, and applying more appropriate econometric techniques. From analyses of twelve parliamentary democracies, we find that macroeconomic performance and political context exert significant influence on election timing. All other factors being equal, better performances in terms of economic growth, inflation, and unemployment will make a government more likely to call an early election. Controlling for government ideology, we find that right-wing governments are more sensitive to inflation performance while left-wing governments are more sensitive to the level of unemployment.
The relationship between permeant size and permeability in lipid bilayer membranes.

Permeability coefficients (P m ) across planar egg lecithin/decane bilayers and bulk hydrocarbon/water partition coefficients (K w→hc) have been measured for 24 solutes with molecular volumes, V, varying by a factor of 22 and P m values varying by a factor of 107 to explore the chemical nature of the bilayer barrier and the effects of permeant size on permeability. A proper bulk solvent which correctly mimics the microenvironment of the barrier domain was sought. Changes in P m /Kw→hc were then ascribed to size-dependent partitioning and/or size-dependent diffusivity. The diffusion coefficient-size dependency was described by D barrier = D 0 /V n . When n-decane was used as a reference solvent, the correlation between log P m /K w→hc and log V was poor (r = 0.56) with most of the lipophilic (hydrophilic) permeants lying below (above) the regression line. Correlations improved significantly (r = 0.87 and 0.90, respectively) with more polarizable solvents, 1-hexadecene and 1,9-decadiene. Values of the size selectivity parameter n were sensitive to the reference solvent (n = 0.8 ± 0.3, 1.2 ± 0.1 and 1.4 ± 0.2, respectively, for decane, hexadecene, and decadiene). Decadiene was selected as the most suitable reference solvent. The value for n in bilayer transport is higher than that for bulk diffusion in decane (n = 0.74±0.10), confirming the steep dependence of bilayer permeability on molecular size. Statistical mechanical theory recently developed by the authors suggests that a component of this steep size dependence may reside in size-dependent solute partitioning into the ordered chain region of bilayers. This theory, combined with the above diffusion model, yielded the relationship, P m /K W→hc=D 0 exp(™αV)V n . A fit of the experimental data to this model gave the best fit (r=0.93) with α = 0.0053±0.0021 and n=0.8 ± 0.3, suggesting that both diffusion and partitioning mechanisms may play a role in determining the size dependence of lipid bilayer permeabilities.
The Application of Intelligent Keywords to Patient Adherence Management System

Health behavior change is the key challenge for healthcare intervention adherence management. For each treatment planning, patient adherence can be managed, audited, and improved by the Patient Adherence Management System applying Intelligent Keyword PAMSIK featuring the use of intelligent keywords, which has been design to navigate users to the target in-time knowledge and also leverage the collective power-peer learning to encourage patients. Three major components of PAMSIK are: an autonomous, intelligent, friendly User Behavior Collector to identify patient's personal adherence problems, a Patient Similarity Analyzer to dynamically cluster peers, and a Cure Service Dispatcher to recommend suitable cures and thus deliver prompt services and in-time contents to users.
The future of the factory

Abstract The basic driving force that will determine the future of the factory is likely to be the margin of profitability. In rapidly changing high technology industry the advances in product design will enable them to increase the margin of profitability through increases in the selling price, whereas in more traditional industries it must be obtained by decreasing the total manufacturing cost. Among the most important factors that will affect the manufacturing cost are, in order of importance, information management (which determines the indirect cost), the materials cost, the direct labor cost, and the capital cost. In order to reduce the direct cost, computers will be used extensively to integrate the entire manufacturing system, ranging from design to manufacturing processes to quality control. For computer-integrated manufacturing systems to be effective, more intelligent machines should be developed to minimize the information flow. However, the single most important thing that will always have the most significant effect on margin of profitability, and thus on the factory of the future, will be the ability to make rational decisions during the synthesis of processes and products. The yield of electronic component fabrication processes, the efficiency of mechanical products, the productivity of a factory, and the portability and efficiency of software can be improved when design decisions are evaluated using the synthesis axioms. Therefore, the factory of the future should not only involve computer-integrated manufacturing systems, but also the computers should be provided with intelligence so as to enable them to make correct decisions and aid the decision makers at all levels of industrial hierarchy.
Arbitrary discontinuities in space–time finite elements by level sets and X-FEM

An enriched finite element method with arbitrary discontinuities in space–time is presented. The discontinuities are treated by the extended finite element method (X-FEM), which uses a local partition of unity enrichment to introduce discontinuities along a moving hyper-surface which is described by level sets. A space–time weak form for conservation laws is developed where the Rankine–Hugoniot jump conditions are natural conditions of the weak form. The method is illustrated in the solution of first order hyperbolic equations and applied to linear first order wave and non-linear Burgers' equations. By capturing the discontinuity in time as well as space, results are improved over capturing the discontinuity in space alone and the method is remarkably accurate. Implications to standard semi-discretization X-FEM formulations are also discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Mechanism involving a preceding structural change in homogeneous redox catalysis

Abstract In this work we report examples of a preceding structural change in homogeneous redox catalysis. This behavior was encountered in the catalyzed reduction of xanthylideneanthrone, 1 , and thioxanthylideneanthrone, 2 . The neutral form of each of these compounds exists in two structures, a minor form (B) and a major form (A). However, in the anion radicals, the preference is reversed with B − predominating over A − . Normal redox catalysis would involve the reduced form of the catalyst, Q, reacting in an uphill reaction with A to produce A − and P, the oxidized form of the catalyst. The unfavorable reaction would be driven by the rapid conversion of A − to B − . In the case of 1 and 2 , however, Q instead reacts with the minor form, B, and the extent of catalysis can be used to evaluate the rate and equilibrium parameters for the preceding structural change, the A ⇌ B reaction.
Extinction of a fast-growing oyster and changing ocean circulation in pliocene tropical America

Ocean circulation changed profoundly in the late Cenozoic around tropical America as a result of constriction and final closure of the Central American seaway. In response, regional planktonic productivity is thought to have decreased in the Caribbean Sea. Previous studies have shown that shallow-marine communities reflect these changes by reorganizing from a suspension-feeder– dominated community to a more carbonate-rich, phototrophic-based community. Although changes in diversity, abundance, and body size of various shallow-marine invertebrates have previously been examined, no study has specifically used growth rate in suspension feeders to examine the effect that changes in ocean circulation may have had on shallow-marine communities. Here we show that a fast-growing oyster went extinct concurrently with changes in ocean circulation and planktonic productivity in the Pliocene. Faster-growing Crassostrea cahobasensis went extinct, whereas slower-growing Crassostrea virginica and columbiensis survived to the Holocene. Miocene–Pliocene C. cahobasensis grew 522% faster in shell carbonate and 251% faster in biomass relative to Quaternary C. virginica and C. columbiensis . Although differences in growth are due to proximate differences in environment, the disappearance of faster-growing C. cahobasensis from shallow-marine environments and the continued survival of slower-growing C. virginica and C. columbiensis in marginal-marine environments (e.g., estuaries, lagoons) is consistent with the view that concurrent changes in ocean circulation and declining primary production resulted in the restriction of Crassostrea to marginal-marine environments.
Phase-field simulation of intergranular bubble growth and percolation in bicrystals

Abstract Three-dimensional phase-field simulations of the growth and coalescence of intergranular bubbles in bicrystal grain geometries are presented. We investigate the dependency of bubble percolation on two factors: the initial bubble density and the bubble shape, which is governed by the ratio of the grain boundary energy over the surface energy. The simulations show that variations of each of these factors can lead to large discrepancies in the bubble coalescence rate, and eventual percolation, which may partially explain this observed occurrence in experimental investigations. The results presented here do not account for concurrent gas production and bubble resolution due to irradiation, therefore this simulation study is most applicable to post-irradiation annealing.
Evaporation and combustion of sprays

A description is provided of recent spray evaporation and combustion models, taking into account turbulent two- and three-dimensional spray processes found in furnaces, gas turbine combustors, and internal combustion engines. Within the class of spray models of interest, two major categories are distinguished, including locally homogeneous flow (LHF) models and separated flow (SF) models. SF models are of the greatest practical importance, but LHF models have distinct advantages in some cases. Attention is also given to recent progress on modeling interactions between drops and the flow in both dilute and dense sprays, involving sprays having low and high liquid volume fractions, respectively.
The development of cubic-carbide-free surface layers in cemented carbides without nitrogen

Abstract In cemented carbides, the surface-region composition can be modified to provide added toughness for coated cutting-tool substrates by developing a cobalt-enriched, cubic-carbide-free surface layer. Typically, such modifications have been prepared by establishing nitrogen gradients in the cemented carbide through the additions of cubic nitrides or nitrification of the cubic carbides during sintering. Recently, methods have been developed for forming cubic-carbide-free surface layers in compositions without the intentional addition of nitrogen. In this study, the kinetics of formation of such layers are compared for compositions with and without nitrogen. The effects of sintering atmosphere and cubic-carbide composition are also discussed.
Abstract 4002: Differential regulation of the ERGF-MAPK pathway by deoxycholic acid (DCA) and Ursodeoxycholic acid (UDCA) in colon cancer.

Obesity and a western diet are risk factors for the development of colorectal cancer and correlate with high levels of bile acids. Specifically, the secondary bile acid deoxycholic acid (DCA) has been shown to act as a tumor promoter in animal studies. Interestingly, the tertiary bile acid Ursodeoxycholic acid (UDCA) was found to have chemopreventive activity in a clinical trial conducted in 1285 individuals with recently resected colorectal adenomas. The mechanism(s) of DCA9s tumor promoting effects and UDCA9s chemopreventive activities are unclear, however DCA and UDCA have been previously shown to regulate EGFR-MAPK signaling in a differential manner. Because this mitogenic pathway has been shown to play a role in colon cancer cell proliferation and survival, we hypothesize that DCA9s tumor promoting effect may stem from its regulation of this mitogenic pathway. We therefore examined the role of DCA in the regulation of the EGFR MAPK pathway in human colon cancer cells as compared to UDCA. Our findings show that DCA can induce ERK1/2 phosphorylation in an EGFR-independent manner in HT-29 colon adenocarcinoma cells, and that this is at least partially dependent on PI3K activation. We also determined that UDCA pretreatment was able to suppress both EGF and DCA-induced EGFR-MAP signaling. By elucidating the mechanism by which DCA and UDCA differentially regulate colon cancer proliferation and survival, we may be able to skew the signaling in colon cancer cells to favor chemoprevention as opposed to tumorgenesis. Citation Format: Sara M. Centuori. Differential regulation of the ERGF-MAPK pathway by deoxycholic acid (DCA) and Ursodeoxycholic acid (UDCA) in colon cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4002. doi:10.1158/1538-7445.AM2013-4002
Pulmonary vascular occlusion and fibrosing mediastinitis.

Patients with fibrosing mediastinitis causing obstruction of pulmonary veins and arteries may present with many of the historic, physical, and laboratory findings of patients with pulmonary hypertension due to chronic thrombotic obstruction of major pulmonary arteries. Because the latter is subject to surgical correction, and the former is not, it is important to differentiate between the two and to be aware of the similarities in presentation. Three patients with pulmonary hypertension due to compression of pulmonary veins and the right pulmonary artery by fibrosing medias tinitis are presented who illustrate these points. A review of the literature documents other instances in which vascular involvement due to fibrosing mediastinitis has mimicked other types of pulmonary hypertension.
Effects of caudate nuclei or frontal cortical ablations in kittens: Responsiveness to auditory stimuli and comparisons with adult-operated littermates

Abstract These experiments assess the behavioral responsiveness of adult cats with extensive caudate nuclei or frontal cortical ablations, sustained either neonatally or in adulthood, to presentations of cat vocalizations or of tones. Each subject received 27 presentations, at 1-min intervals, of a 12 s sequence of taped vocalization (calls) on 2 successive days and, 1 week later, a similar series of 2-kHz tones of the same duration and intensity. The behavioral responses were scored using a six-point rating scale and the data were analyzed to compare responsiveness of the groups within each testing day, decrement of responsiveness across the trials of each session (habituation), and retention of habituation across successive days. We found that (a) all acaudate and afrontal cats persisted in responding at higher levels than intact animals in all three testing sessions; (b) the cats with caudate ablations were more responsive than those with frontal ablations to both calls and tones; (c) the hyperresponsiveness was more marked for adult-operated in relation to kitten-operated preparations; (d) in general, the responsiveness of all kitten groups decreased progressively across the three testings; and (e) for the adult-operated cats, there was a decrement between the two call sessions and an increase between the call and the tone sessions. These findings suggest that both the caudate nucleus and the frontal cortex participate in processes controlling the organism's responsiveness to external stimuli with the caudate removal producing the largest defect; they also indicate that, with some qualifications, the lesions sustained by the kitten result in less marked later effects than those sustained by the adult. Furthermore, they may help to explain some of the behavioral changes which we described previously for cats with caudate ablations.
Generalized intersection and projection bodies

Generalized intersection and projection bodies are defined and constructed for a spatial convex polytope P. The generalized intersection body extends the definition of the classical Petty body, while the generalized projection body can be considered a dual formulation of the base construction. The method of construction is outlined and an example is used to illustrate the induced structures.
Whose body is it anyway? Disputes over body tissue in a biotechnology age

In this changing context, developments in the removal, storage, and transformation of human tissue have created new opportunities for medical research and biotechnological applications that have increased demands for tissue. Body tissue has become a part of an international market. For example, a company has obtained American and European patents on the process of extracting stem cells from cord blood; and pharmaceutical companies are searching the world for disease genes and sometimes patenting them. As the market for human tissue has increased, so have disputes in which scientific and commercial ideas about the proper uses of tissue confront social and personal understandings about the body. Whereas scientists seek greater access to bodily materials, others defend their cultural values and individual rights. Scientists need to pay greater heed to such social claims, for they reflect legitimate interests and further other important social values and activities. Indeed, courts and other policymaking bodies are struggling to develop systems to accomodate productive use of bodily materials while respecting cultural associations and individual rights. And they are increasingly incorporating social meanings of the body into their decisons.
Stochastic true digestible amino acid values

Abstract The concept of using amino acid digestibility coefficients has been reported to be valuable in formulating diets to meet the requirements of livestock. Digestibility coefficients of nutrients reflect the amounts of components of a feedstuff that become available to meet livestock requirements. Most biological factors, including feed ingredient amino acid means and their digestibility values, have variabilities associated with them. Chance constrained (stochastic) programming for feed formulation has been suggested as a method that accounts for variability. The ingredient matrix for stochastic formulation requires means and standard deviations (S.D.s) for all nutrients involved in the formulation. Several references were used to provide ingredient amino acid means and S.D.s, and true digestibility coefficient means and S.D.s. When there is variability associated with two or more variables in a calculation (e.g. nutrient mean and S.D., coefficient of true digestibility mean and S.D.), it is a nonlinear problem involving the application of the principles of probability theory for a solution. It is a mathematical oversimplification to multiply an amino acid S.D. by the coefficient of true digestibility for the calculation of the digestibility S.D. This technique would result in an under-estimation of the S.D. associated with the digestibility of the amino acid. A Microsoft Excel © 2000 Spreadsheet was used to input data from references and to develop formulae based on probability theory. Values derived from these formulae were summarized in reference tables. A Monte Carlo simulation verified the analytical results of the multiplication of the means and S.D.s of the amino acid value and its coefficient of true digestibility.
A Comparison Between the Monte Carlo Ray Trace and the FLUENT Discrete Ordinates Methods for Treating Solar Input to a Particle Receiver

A new type of high temperature solar receiver for Brayton Cycle power towers is being designed and built in the Combustion and Solar Energy Laboratory at San Diego State University under a DOE Sunshot Award. The Small Particle Solar Receiver is a pressurized vessel with a window to admit concentrated solar radiation that utilizes a gas-particle suspension for absorption and heat transfer. As the particles absorb the radiation that enters the receiver through the window, the carrier fluid (air in this case) heats which oxidizes the particles and the flow leaves the receiver as a clear gas stream. After passing through an in-line combustor if needed, this hot gas is used to power a turbine to generate electricity.The numerical modelling of the receiver is broken into three main pieces: Monte Carlo Ray Trace (MCRT) method (written in FORTRAN), ANSYS Fluent (CFD), and the User Defined function (written in C code) for oxidation. Each piece has its advantages, disadvantages, and limitations and the three pieces are coupled to finalize the calculation. While we have successfully demonstrated this approach to obtaining the velocity and temperature fields, one big challenge to this method is that the definition of the geometry is a time consuming programming task when using MCRT. On the other hand, arbitrary geometries can be easily modelled by Computational Fluid Dynamics (CFD) codes such as FLUENT.The goal of this study is to limit the use of MCRT method to determining the appropriate input boundary condition on the outside of the window of the receiver and to use the built-in Discrete Ordinates (DO) method for all the radiation internal to the receiver and leaving the receiver due to emission. To reach the goal, this paper focuses on the DO method implemented within FLUENT. An earlier study on this subject is based and advanced. Appropriate radiation input for the DO method is extensively discussed. MIRVAL is used to simulate the heliostat field and VEGAS is used to simulate a lab-scale solar simulator; both of these codes utilize the MCRT method and provide intensity information on a surface. Output from these codes is discretized into DO parameters allowing the solution to proceed in FLUENT. Suitable benchmarks in FLUENT are used in a cylindrical geometry representing the receiver for the comparison and validation. This method will allow FLUENT to be used for a variety of problems involving concentrated solar energy.Copyright © 2014 by ASME
Rotation and Cover Crop Effects on Soilborne Potato Diseases, Tuber Yield, and Soil Microbial Communities

Seven different 2-year rotations, consisting of barley/clover, canola, green bean, millet/rapeseed, soybean, sweet corn, and potato, all followed by potato, were assessed over 10 years (1997-2006) in a long-term cropping system trial for their effects on the development of soilborne potato diseases, tuber yield, and soil microbial communities. These same rotations were also assessed with and without the addition of a fall cover crop of no-tilled winter rye (except for barley/clover, for which underseeded ryegrass was substituted for clover) over a 4-year period. Canola and rapeseed rotations consistently reduced the severity of Rhizoctonia canker, black scurf, and common scab (18 to 38% reduction), and canola rotations resulted in higher tuber yields than continuous potato or barley/clover (6.8 to 8.2% higher). Addition of the winter rye cover crop further reduced black scurf and common scab (average 12.5 and 7.2% reduction, respectively) across all rotations. The combined effect of a canola or rapeseed rotation and winter rye cover crop reduced disease severity by 35 to 41% for black scurf and 20 to 33% for common scab relative to continuous potato with no cover crop. Verticillium wilt became a prominent disease problem only after four full rotation cycles, with high disease levels in all plots; however, incidence was lowest in barley rotations. Barley/clover and rapeseed rotations resulted in the highest soil bacterial populations and microbial activity, and all rotations had distinct effects on soil microbial community characteristics. Addition of a cover crop also resulted in increases in bacterial populations and microbial activity and had significant effects on soil microbial characteristics, in addition to slightly improving tuber yield (4% increase). Thus, in addition to positive effects in reducing erosion and improving soil quality, effective crop rotations in conjunction with planting cover crops can provide improved control of soilborne diseases. However, this study also demonstrated limitations with 2-year rotations in general, because all rotations resulted in increasing levels of common scab and Verticillium wilt over time.
Collisional Activation of Large Molecules Is an Efficient Process

It is a common perception that as molecules become larger they become inherently more difficult to activate and dissociate in the gas phase, especially under low energy collision induced dissociation (CID) conditions. This difficulty has been attributed both to the inefficiency of the collisional activation process and to the requirement of higher levels of internal excitation to induce dissociation. A serious consequence of this supposition is the implied difficulty of using CID methods to sequence peptides and proteins.
Neural network sensor fusion for security applications

Neural networks can detect patterns in information that they receive and have been used successfully in many classification problems. The research discussed in this paper was pursued to determine if neural networks could be successfully used for alarm classification for security systems operating in unstructured environments. The project investigated the usefulness of various types of neural networks for this application. The results from the research exceeded the original goals, promising sound application to security systems in unstructured environments.
Picosecond photoluminescence spectroscopy in highly excited semiconductors

Time-resolved photoluminescence is universally regarded as a very useful probe in the investigation of the dynamic behavior of high density electron-hole systems in direct-gap semiconductors, in which carrier lifetimes are of the order of nanoseconds or less. Two applications of this technique include (1) the observation of excitons in which a conduction electron and a valence hole are bound to one another via the long-range Coulomb interaction and (2) the formation of excitonic molecules (or biexcitons), which is caused by the attractive covalent bonding between two single excitons. This paper reviews transient photoluminescence techniques used recently in the study of such highly excited systems. Interaction between excitons at high concentration is discussed, and some experimental results for ZnSe and GaAs are presented.
Thermocapillary convection in a rectangular cavity with a deformable interface

A finite-volume method and a boundary element technique are used to compute two-dimensional (2D) thermocapillary convection in a rectangular cavity. The free surface is deformable and the deviations from a flat interface, h, are assumed small in the finite-volume calculations as appropriate for small Capillary (Ca). Two asymptotic approaches are employed; the first is an expansion valid as Ca tends towards 0 and the second assumes h tends towards 0, retaining Ca explicitly as a parameter. On the other hand, the boundary elements approach can be used with O(1) surface deformations. These three different formulations are used to calculate thermocapillary motions in fluids with small Prandtl numbers of about 0.01, Ca less than 0.05, aspect ratios (width/height) 1, 2 and 4, and various values of the Maragoni number (Ma). The same solutions are calculated with these different approaches and are found in good agreement for values of Ca up to 0.05. All solutions calculated are steady, which is both in agreement and disagreement with recently published results by different authors employing different numerical techniques.
On creating sets with large lower density

Abstract Given a set A whose density and Banach density are equal (such sets can be found “inside” any set with positive Banach density) it is shown, as a corollary to a more general theorem, that the union of finitely many translates of A has arbitrarily large lower density. Examples are given to show that the general theorem is best possible.
Variable-Temperature Electron Paramagnetic Resonance Studies of Copper-Exchanged Zeolites

Abstract Copper-exchanged zeolites, Beta and ZSM-5, were studied using variable-temperature electron paramagnetic resonance (EPR) spectroscopy to probe changes in the local environment of the Cu 2+ centers when samples were dehydrated and heated in flowing helium or under reagent flow. Hydrated samples of Cu-ZSM-5 and Cu-Beta exhibited EPR spectra consistent with EPR signals previously assigned to Cu 2+ in distorted octahedral coordination. EPR spectra of dehydrated Cu-Beta and Cu-ZSM-5 showed the presence of coordination environments that were similar to EPR signals previously assigned to Cu 2+ in distorted square pyramidal and distorted square planar environments. An empirical model is presented that correlates g ∥ and A ∥ for a series of copper-exchanged zeolites and model compounds and provides additional insight into the coordination environment of Cu 2+ in copper-exchanged zeolites. The empirical model links a number of past EPR studies on different copper-exchanged zeolites and provides an explanation for the observed trends in EPR parameters related to the charge at the copper center. The EPR spectra for dehydrated Cu-ZSM-5 and Cu-Beta samples exhibited a temperature dependence. The EPR spectrum of Cu-ZSM-5 and Cu-Beta recorded at 673 K showed an increase in g ∥ and a decrease in A ∥ when compared with the EPR spectrum recorded at room temperature. These changes in spectral parameters are attributed to changes in the electronic environment of the Cu 2+ species through modification of the coordination environment.
Mixed carbonate-siliciclastic infilling of a Neogene carbonate shelf-valley system: Tampa Bay, West-Central Florida

Abstract The shelf-valley system underlying Tampa Bay, Florida’s largest estuary, is situated in the middle of the Neogene carbonate Florida Platform. Compared to well-studied fluvially incised coastal plain valley systems, this shelf-valley system is unique in its karstic origin and its alternating carbonate-siliciclastic infill. A complex record of sea-level changes, paleo-fluvial variability and marine processes have controlled the timing and mechanisms of this ‘compound’ shelf-valley infill. A dense grid of high-resolution, single-channel seismic data were collected at the mouth of Tampa Bay, in an attempt to define this stratigraphy, determine the controls on deposition, and define the underlying structure of this shelf-valley system. The seismic data were correlated with nearby wells and boreholes for lithologic and age control. Sequence stratigraphic methods were incorporated in order to develop an integrated chronostratigraphy for the depositional infilling of the shelf-valley system. Five seismic sequences were identified. Sequence boundaries generally show erosional truncation and karstification, with downlap of overlying sequences. Structure contour and isopach maps indicate that the Tampa Bay shelf-valley system has remained in essentially the same location since its formation in the early Miocene, although the provenance of sedimentary infill has changed. This change is due to increasing amounts of siliciclastic material during the Neogene. Seismic facies interpretations indicate lower-energy, northward prograding deposition dominated by predominantly carbonate sediments within the lowest Sequence A. Higher energy, siliciclastic fluvio-deltaic deposition within sequences B and C originates to the east and northeast of the shelf-valley system related to a Pliocene pulse of sedimentation onto the Florida Platform. Finally, marine processes (longshore transport, ebb-tidal delta formation) dominate the upper two sequences (D and E), reworking these siliciclastic sediments into a spatially mixed carbonate-siliciclastic depositional setting.
Studies on the mechanism of fatty acid synthesis III. Products of enzymic synthesis of fatty acids

Abstract The long-chain fatty acids synthesized from acetate by an enzyme system reconstructed fom soluble fractions of pigeon liver have been separated and identified by a variety of techniques. Free palmitic acid and progressively smaller amounts of free myristic, lauric and decanoic acids are principally formed in this system. Small quantities of esterified long-chain acids with the properties of palmityl CoA were also found. Short-chain fatty acids do not accumulate, but small amounts of the hydroxamates of short-chain acids can be formed if acetyl CoA is used as substrate in place of acetate. HMG has been identified in the incubation mixture. Net synthesis of fatty acids was demonstrated by direct weighing, titration and radioactivity measurements. The specific radioactivity of the carboxyl carbon of fatty acids synthesized from carboxyl-labeled acetate was 1.7 times that of the average carbon atom in the entire chain. This finding is in agreement with the concept of fatty acid synthesis via head-to-tail condensations of acetate units.
The Genetics of Dietary Experience in a Restricted Natural Population

The sources of individual differences in human and non-human animals remain controversial. We demonstrate that diet and genetics interact in determining the ontogenetic trajectory of chemosensory and prey preferences in the common garter snake, Thamnophis sirtalis, a dietary generalist. In litters of neonate snakes from a single small field in an earthworm-ingesting population, initial responses to chemical cues from fish and worm were similar, with zero heritabilities. After 12 meals on fish, however, the heritability of both fish and worm chemosensory responses increased markedly, the change in response to fish but not worm chemicals was heritable, the relative preference for fish versus worm was heritable, and the change in relative preference was heritable. In addition, growth rates on each diet were related to changes in chemoreceptive responses. Such genetic-environment variation that emerges only after equivalent ontogenetic experience may be a factor in responses to environmental change in many species.
Stratospheric cooling and perturbation of the meridional flow during the solar eclipse of 7 March 1970.

Abstract Eight ARCAS meteorological rockets were fired from Wallops Island (38N, 75W) before, during and after the total solar eclipse of 7 March 1970. Detailed temperature and wind data were acquired to an altitude of about 65 km. Pressures and densities were derived by hydrostatic integration of the corrected temperature profiles. A time-height cross section of the temperature data (smoothed to suppress small-scale detail) shows significant cooling mainly in the layer 40–60 km. Maximum amplitude of the temperature perturbation is about 9K, near 50 km. Maximum pressure variation, amounting to a decrease of at least 7%, occurred about one scale height higher, near 58 km. The ARCAS wind observations are independent of the thermodynamic measurements; a time-height analysis of the winds shows a large amplification of the meridional flow, which is found to be consistent with the observed pressure changes. Derivatives in the perturbation equation of motion are evaluated with the aid of a space-time transformat...
Chlorambucil vs. combined chlorambucil-corticosteroid therapy in chronic lymphocytic leukemia.

Eleven patients with chronic lymphocytic leukemia were treated with chlorambucil alone and 15 patients received combined chlorambucil-prednisone therapy in a double-blind study. Mean age, duration of disease, physical findings, and hematologic data in the two groups were essentially comparable. Complete remission was observed in 3 and partial remission in 10 of the patients in the chlorambucil-prednisone treated group; but only one of the patients obtained complete and four showed partial remission with chlorambucil alone. This difference was statistically significant (p < 0.05). Hematologic toxicity was less frequent in the combination group. Two-year survival was 93% for combination group and 54% for chlorambucil-treated group. The difference, however, was not statistically significant. Our data indicate that chlorambucil-prednisone therapy is superior to chlorambucil in the treatment of chronic lymphocytic leukemia.
Noninvasive measurements of activity-induced changes in muscle metabolism

Abstract Two noninvasive measurement techniques were used to monitor activity-induced changes in skeletal muscle in humans. Phosphorus magnetic resonance spectroscopy (P-MRS) was used to measure changes in energy metabolism by measuring the ratio of inorganic phosphate to phosphocreatine ( Pi PCr ) during steady level work in the wrist flexor muscles in a 30 cm bore, 1.9 Telsa magnet, and the rate of PCr recovery from exercise in the calf muscles in a 76 cm bore, 1.8 Tesla magnet. Near red spectroscopy (NRS) was used to measure changes in oxygen saturation of hemoglobin and myoglobin during and after exercise. Fourteen days of wrist flexion exercise resulted in significant improvement in muscle metabolism as measured by MRS. This improvement disappeared after 35 days of inactivity. Indications of muscle stress during training such as muscle soreness and decreased maximum strength were associated with increases in resting Pi PCr . A similar training protocol using plantar flexion exercise resulted in an improved rate of PCr resynthesis, which returned to control values 42 days after training stopped. NRS measurements of the wrist flexor muscles during a ramp exercise protocol demonstrated a decrease in the oxygen saturation of hemoglobin-myoglobin from 60% at rest to 15% at the highest work levels. The half time of recovery of oxygen saturation was faster than that of PCr in both young and old subjects, supporting the hypothesis that oxygen delivery is not rate limiting in submaximal exercise in healthy individuals.
The Interaction of the Photoperiod and Testosterone in Regulating Serum Gonadotropin Levels in Castrated Male Hamsters

Castrated adult male golden hamsters maintained on either a stimulatory (LD 14:10) or a nonstimulatory (LD 6:18) light cycle for 10 weeks following surgery were implanted sc with empty or testosterone-filled Silastic capsules of various lengths. Capsules which maintained circulating androgen levels between 0.5 and 1.7 ng/ml reduced serum levels of LH and FSH in castrated animals exposed to LD 6:18 but not in animals maintained on LD 14:10. When serum androgen levels were maintained at about 3 ng/ml, serum gonadotropin levels were reduced 30–35-fold in nonphotostimulated hamsters but only 2–3-fold in photostimulated animals. Maintenance of serum androgen levels at 14–17 ng/ml induced a maximum decrease in serum LH and FSH in animals exposed to either photoperiod. These results indicate that exposure to short days for 10 weeks renders the hypothalamic-hypophyseal axis of the castrate hamster extremely sensitive to the negative feedback effect of testosterone. This alteration in steroid feedback sensitivity ...
Cerebral blood flow, blood volume, and vascular permeability of cerebral glioma assessed with dynamic CT perfusion imaging

We report dynamic CT perfusion imaging assessment of hemodynamics in a patient with a high-grade cerebral glioma and compare our results to those of previously published studies.
Employee and job attributes as predictors of absenteeism in a national sample of workers: The importance of health and dangerous working conditions

This study reports on research which looks for employee and job characteristics which correlate with absenteeism. A large cross-sectional national probability sample of workers employed for at least 20 hr per week is analyzed (n = 1308). The dependent variable is the number of self-reported absences during the past 14 days. Thirty-seven independent variables are considered. Ordinary Least Squares (multiple regressions), two-limit Tobits, and two-part models are used to assess the statistical and practical significance of possible covariates. Statistically significant predictors included health variables such as being overweight, complaining of insomnia, and hazardous working conditions; job characteristics such as inflexible house; and personal variables such as being a mother with small children. Variables reflecting dangerous working conditions appear to be the strongest correlates of absenteeism. Notable variables which do not predict absenteeism include age, race, wages, and job satisfaction. Future research should direct attention toward workers' health and working conditions as covariates of absenteeism, since they are strongly significant in this study and have been neglected by most absenteeism investigators.
GAD65 Autoantibodies Detected by Electrochemiluminescence Assay Identify High Risk for Type 1 Diabetes

The identification of diabetes-relevant islet autoantibodies is essential for predicting and preventing type 1 diabetes (T1D). The aim of the current study was to evaluate a newly developed electrochemiluminescence (ECL)-GAD antibody (GADA) assay and compare its sensitivity and disease relevance with standard radioassay. The assay was validated with serum samples from 227 newly diagnosed diabetic children; 68 prediabetic children who were prospectively followed to T1D; 130 nondiabetic children with confirmed islet autoantibodies to insulin, GAD65, IA-2, and/or ZnT8 longitudinally followed for 12 ± 3.7 years; and 181 age-matched, healthy, antibody-negative children. The ECL-GADA assay had a sensitivity similar to that of the standard GADA radioassay in children newly diagnosed with T1D, prediabetic children, and high-risk children with multiple positive islet autoantibodies. On the other hand, only 9 of 39 nondiabetic children with only a single islet autoantibody (GADA only) by radioassay were positive for ECL-GADA. GADA not detectable by ECL assay is shown to be of low affinity and likely not predictive of future diabetes. In conclusion, the new ECL assay identifies disease-relevant GADA by radioassay. It may help to improve the prediction and correct diagnosis of T1D among subjects positive only for GADA and no other islet autoantibodies.