cssi/SciSciGPT-SciSciNet huggingface dataset:
De-risking Pharmaceutical Tablet Manufacture Through Process Understanding, Latent Variable Modeling, and Optimization Technologies

In pharmaceutical tablet manufacturing processes, a major source of disturbance affecting drug product quality is the (lot-to-lot) variability of the incoming raw materials. A novel modeling and process optimization strategy that compensates for raw material variability is presented. The approach involves building partial least squares models that combine raw material attributes and tablet process parameters and relate these to final tablet attributes. The resulting models are used in an optimization framework to then find optimal process parameters which can satisfy all the desired requirements for the final tablet attributes, subject to the incoming raw material lots. In order to de-risk the potential (lot-to-lot) variability of raw materials on the drug product quality, the effect of raw material lot variability on the final tablet attributes was investigated using a raw material database containing a large number of lots. In this way, the raw material variability, optimal process parameter space and tablet attributes are correlated with each other and offer the opportunity of simulating a variety of changes in silico without actually performing experiments. The connectivity obtained between the three sources of variability (materials, parameters, attributes) can be considered a design space consistent with Quality by Design principles, which is defined by the ICH-Q8 guidance (USDA 2006). The effectiveness of the methodologies is illustrated through a common industrial tablet manufacturing case study.
Cadmium zinc telluride high-resolution detector technology

Electrode contacting on semiconductor radiation detectors has been a topic of active interest in many recent investigations. Research activities have focused on the morphology and chemistry of modified surfaces using sophisticated preparation techniques and employing characterization methods that are able to discriminate between surface and bulk effects. From an applied point of view, the detector fabrication technology involves a series of fabrication steps which can be optimized. Results of an ongoing effort to improve the performance of high resolution CdxZn1-xTe spectrometers by addressing wafer surface preparation, electrode deposition and contact passivation are described.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The Evolution of Complexity in Primitive Exchange: Theory

Abstract Complex economies require monetary or real inventories to ensure bilateral trade at clearing prices. Trade in simpler economies is rationed by debt-status and is neither bilateral nor clearing. Each type of exchange minimizes transaction costs for characteristic levels of population, division of labor, and supply variability. Transaction costs are accounted for as the time and the number of computational steps needed for trade. Kinship alliances are shown to mitigate the cooperative problem of each exchange system. In systems without clearing prices, kinship supports the repayment of debts among households of the same generation. In price-clearing systems that need long-term inventories, on the other hand, kinship is focused on intergenerational bequests. J. Comp. Econom. February 1995, 20 (1), pp. 1-31. Rensselaer Polytechnic Institute, Troy, New York 12180.
Oxide properties of a γ-TiAl: a surface science study

Abstract The surface properties of oxides grown on a γ-TiAl (2 at.% Nb) have been examined using X-ray photoelectron spectroscopy and secondary ion mass spectroscopy. An oxide formed on the sample during air exposure at room temperature was thermally destabilized in ultrahigh vacuum. The heating largely decomposed the advanced titanium oxidation states to give a dominant +2 valence configuration at 600 °C, while the aluminum oxide was somewhat enhanced for the same treatment. Growth of a post chemisorption oxide for various temperatures and exposure times at or below a pressure of 10 −6 Torr oxygen revealed the progressive development of titanium and aluminum oxide. At a temperature of 600 °C the titanium component was greatly enhanced relative to the aluminum content in the surface region. This separation of titanium from aluminum was clearly visible in SIMS measurements. The development and thermal stability of these oxides is in agreement with the heats of formation and available valence states for the two majority components in the material.
Guided Inquiry Learning in a Thermodynamics Class

This paper describes guided inquiry investigations of thermodynamic properties and cycles that was used in a sophomore thermodynamics class. A partially-complete computer model of a Carnot cycle was provided to students that was written in Engineering Equation Solver (EES). The students were led through a investigation in pairs or groups using the model designed to familiarize the students with the software as well as the cycle. As part of the investigation, the students were required to modify the model to add features. Following the in-class exercise with the Carnot cycle, students were required to model a Stirling cycle and later a Brayton cycle using the same EES software for a take-home project. In previous classes, the same (and similar) take-home projects were assigned, but this was the first time that these computer projects were preceded by a guided inquiry investigation. The advantages of using such a guided inquiry investigation to introduce the software were primarily evident from the questions that were avoided on the take-home projects, but also evident from the student performance on the projects themselves. A discussion of the investigation is included, as well as critique of what will be changed for the next time the class is taught.Copyright © 2010 by ASME
Frequency response of bipolar junction transistors after electron-beam irradiations

The small-signal frequency response of silicon bipolar junction transistors was measured after the devices were irradiated with electrons below the displacement threshold. The measurements indicated that the high-frequency response of transistors is unchanged by electron irradiation, even though the low-frequency gain is degraded. Whereas process variations intended to change either the gain or cutoff frequency of transistors inevitably affect both, the electron-beam irradiation changes only the gain, giving a clear demonstration of the fact that the cutoff frequency is determined by the physical base transit time. As a practical consequence, the result implies that electron-beam irradiation has relatively little effect on circuit performance. >
Mineral substrates as heterogeneous nucleants in the crystallization of proteins

The effect of mineral substrates (either with good or poor lattice matching to lysozyme) on various factors, including time to nucleation, duration of growth, number and size of crystals, and degree of attachment of protein crystals to the substrates was studied. Crystallization of lysozyme from solutions with conalbumin as a contaminant generally showed that good lattice matching had a beneficial effect on the purity of recovered lysozyme crystals. Current work focuses on the roles played by the chemical composition of the mineral surface as well as the matching of the mineral lattice to that of the crystallizing protein. The experimental observations include the supersaturation required for nucleation and the purity of crystals obtained from solutions contaminated with a protein impurity.
Providing for Quality in Teaching.

If a college professor is an expert in a subject content area, then it follows that he or she is capable of making competent decisions about course or ganization, teaching procedures, select ing and obtaining resources, carrying out the teaching successfully, and then evaluating student learning. At least we often assume this to be true. However, it is not true that teaching competence can be equated with subject competence. There certainly are many capable teach ers on our faculties. But for one reason or another, each person, at different times and for various reasons, needs assistance or guidance in course plan ning, selecting teaching methods and resources, presenting the subject con tent, and in measuring student learning. Quality in undergraduate education depends greatly on giving careful atten tion to instructional planning and im plementation matters. What goes on in a classroom determines in large measure what will be learned, how it is learned, and whether it has been learned. Let us examine some practical situations that provide an understanding of how ac tions that faculty members must take af fect the quality of instruction. Situation A. Dr. Webster is in her sec ond year of college teaching. She feels uncomfortable in lecture courses and
Current Perspective on Aortic Valve Repair and Valve-Sparing Aortic Root Replacement

Aortic valve repair and valve-sparing aortic root replacement are attractive concepts because they offer the possibility of valve competence without structural deterioration due to nonviability and they preclude the need for anticoagulation. Enthusiasm for aortic valve repair has waxed and waned over the past 45 years due in part to the inherent technical difficulties and poor mid-term results. Renewed interest in the concept of aortic valve repair has paralleled the development of valve-sparing aortic root replacement over the last 20 years. A current perspective on aortic valve repair and valve-sparing aortic root replacement is presented in the following review. Historical background, indications for repair, technical considerations, and outcomes data are discussed.
On theory and application of the Helmholtz equation least squares method in inverse acoustics

This paper presents a rigorous mathematical justification of the Helmholtz equation least squares (HELS) method for reconstructing acoustic radiation from an arbitrary source. It is shown that the acoustic pressure radiated from a non-spherical structure can be approximated using the spherical wavefunctions and spherical harmonics, and errors involved in this approximation are bounded. This explains why previously the HELS method could be used to produce satisfactory reconstruction of acoustic radiation from various types of structures. In the present paper, these analytical studies are further supported by experimental validation of the reconstruction of acoustic radiation from a typical filing cabinet in both exterior and interior regions.
First Report of White Pine Blister Rust Caused by Cronartium ribicola on Immune Black Currant Ribes nigrum Cv. Titania in Preston, Connecticut

Since the relaxation of federal sanctions on the planting of Ribes crops because of the development of white pine blister rust (WPBR) immune Ribes cultivars (3), a small industry for the production of Ribes fruit for fresh and processing markets was established in New York and surrounding New England states. The majority of Ribes acreage in the region is planted to a WPBR immune black currant R. nigrum cv. Titania. From 2008 to June 2011, symptoms resembling those caused by WPBR pathogen Cronartium ribicola were observed at a large (>12 ha) R. nigrum cv. Titania planting in Preston, CT. In 2008, infection was restricted to a single field (100% incidence), but in 2009, all fields suffered from premature defoliation by late July. In 2010 and 2011, there was considerable incidence (>85%), but premature defoliation was kept in check by chemical management. Symptoms began as chlorotic lesions (0.5 to 4.3 mm in diameter) on both sides of the leaf. These chlorotic lesions had margins delineated by leaf veins and...
Polygonal gratings for wafer scale one-to-many optical clock signal distribution

In contrast to volume holographic material where 1-to-many fanouts are realized using multiplexed volume holograms, we report in this paper the first Si-based surface relief polygonal gratings aiming at optical clock signal distribution application. Surface relief grating with 1 micrometers period (0.5 micrometers feature size) was fabricated using reactive ion beam etch. Both hexagonal and square gratings were demonstrated for 1-to-4 and 1-to-6 fanouts. Surface- normal input and output coupling schemes were carried out with efficiency as high as 65%. Employment of substrate modes in silicon instead of the guided modes greatly releases the required grating spacing for the demonstrated two-way surface-normal coupling. Clock signal distribution operating at 1.3 micrometers with 7.5 GHz clock speed was demonstrated with signal to noise ratio as high as 60 dB.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The non-null distributions in anoya

Under the traditional assumptions, any entry in ANOVA interpreted to include all Linear model analyses] is equivalent in disiributien to a quadratic form Q=[μ1+σ1Z1]2+…+ [μν+σνZν]2]wherein Z1..Zν are independent standard normal variables. Test statisics in ANOVE are distributed as ratio R of two depenbent such quadretic forms. The non-null distribution of R is a mixture of null distributions; the mixing variable is an easy generalitatlon of the Poisson variable. Fast algorithms yield the power function in both fixed and random effects models in AVOVA to user-specified accuracy.
Conformational Dependence of the Electronic Properties of [Fe(SCH3)4]-,2-

The electronic properties of [Fe(SCH3)4]-,2-, a model for the iron−sulfur site in rubredoxin, and the conformational dependence of these properties were investigated with ab initio calculations. Th...
LINC power amplifiers for reducing out-of-band spectral re-growth: A comparative study

The Linear Amplification with Nonlinear Components (LINC) power amplifier structure combiner implementation has an effect on the linearity and efficiency of the design. Understanding and using this tradeoff is helpful to radar and communication designers and can be used to assist in operating with optimum efficiency while meeting spectral mask requirements instituted by regulatory agencies. In this paper, a simulation-based investigation is performed into implementations with a 180-degree coupler and with a Chireix outphasing network. In general, the overall efficiency in both designs is a function of the amplitude modulation of the message signal in the LINC configuration; however, the 180-degree coupler has a potential to obtain higher linearity in many cases due to the isolation of its two input ports. In certain cases of amplitude modulation, however, much of the output power in the 180-degree coupler design is delivered to an unused termination rather than to the network output.
TIDES: bridging cultural, digital and institutional divides in East Texas and beyond

Purpose – The purpose of this paper is to discuss the history of the TIDES (Teaching, Images and Digital Experiences) Program, and demonstrate how TIDES has created mutually beneficial partnerships through sharing resource and collaborating on digital initiatives with a variety of institutions in both Texas and Mexico.Design/methodology/approach – In order to bridge the digital and cultural divide in East Texas classrooms, TIDES has formed partnerships with institutions and educators from Mexico. By offering media rich resources, adapting current curriculum for today's digital environment, and fostering international partnerships, TIDES has built a model for an education program that promotes local and global understanding.Findings – Bringing together teachers from Mexico and Texas has resulted in a better understanding of each culture, which has translated to the classroom. These connections have been further supported by TIDES virtual expeditions, art projects, and primary source documents.Practical imp...
Fusimotor neuron responses to natural stimuli as a function of prestimulus fusimotor activity in decerebellate cats

Summary The discharge of single fusimotor fibers in medial gastrocnemius nerve was recorded in unoperated control (79 units) and in 3–5-day decerebellate (63 units) cats under light pentobarbital anesthesia. Measurements were made of the discharge rate prior to the application of phasic natural stimuli (prestimulus discharge rate, PDR) and of the discharge rate in response to such stimuli (reactive discharge rate, RDR). A sequence of 7 natural stimuli was used. The mean PDR and the Mean RDR for each stimulus were significantly less in decerebellates than in controls. However, the mean difference in discharge rate between PDR and RDR for each stimulus in decerebellates was equal to or greater than that in control preparations. The RDR response pattern in controls, consisting of a unique level of RDR for each of the individual stimuli within the stimulus sequence, was approximately parallel to the RDR pattern in decerebellates. Furthermore, in control animals, a strong linear correlation between RDR and PDR was observed for each of the individual stimuli. Thus, it appeared that are RDR level was a function of both (a) the nature of the applied stimulus, and (b) the PDR associated with that stimulus. Accordingly, the control data were used to generate linear regression models which, for a given stimulus, would predict the RDR associated with any PDR. The generality of the predictive power of the PDR-RDR association was demonstrated through the accurate estimation of RDR values in decerebellate preparations, from utilization of decerebellate PDR values alone. Consequently, we conclude that the sole direct effect of cerebellar ablation on the discharge of hindlimb extensor fusimotor neurons is a change (decrease) of the PDR.
Fiber yield for fully bleached kraft pulps from black locust (Robinia pseudoacacia) and silver maple (Acer saccharinum)

) and silver maple (Acer saccharinum) with emphasis being placed on fiber yield. Black locust had longer fibers, a higher Seifert cellulose content, and a lower lignin content compared to the maple. The results were higher strength and bleached pulp yield for the black locust. The final yields were 49.5% for black locust and 47.7% for maple. These values are significantly higher than the 40–42% that is normally obtained for bleached softwood kraft pulps.
Restoration of digital images with known space-variant blurs from conventional optical systems

Space-variant (SV) digital image restoration methods attempt to restore images degraded by blurs that vary over the image field. One specific source of SV blurs is that of geometrical optical aberrations, which divert light rays as they pass through the optical system away from an ideal focal point. For simple optical system, aberrations can become significant even at moderate field angles. Restoration methods have been developed for some space- variant aberrations when they are individually dominant, but such dominance is not typically characteristic of conventional optical systems. In this paper, an iterative method of restoration that is applicable to generalized, known space-variant blurs is applied to simulations of images generated with a spherical lines. The method is based on the Gauss-Seidel method of solution to systems of linear equations. The method is applied to sub-images having off- axis displacements of up to 453 pixels, and found to be superior in restoration effectiveness to Fourier methods in that range of field angles.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Laminar Cortical Dynamics of 3D Surface Perception: Stratification, transparency, and Neon Color Spreading

The 3D LAMINART neural model is developed to explain how the visual cortex gives rise to 3D percepts of stratification, transparency, and neon color spreading in response to 2D pictures and 3D scenes. Such percepts are sensitive to whether contiguous image regions have the same contrast polarity and ocularity. The model predicts how like-polarity competition at V1 simple cells in layer 4 may cause these percepts when it interacts with other boundary and surface processes in V1, V2, and V4. The model also explains how: the Metelli Rules cause transparent percepts, bistable transparency percepts arise, and attention influences transparency reversal.
Theoretical analysis of subtractive color mixture characteristics V—Centroid of subtractive tristimulus values

In additive color mixture, when more than two component tristimulus values are given then the mixture result is determined from a linear combination of the components. On the other hand, in subtractive color mixture, the resultant tristimulus values are not uniquely determined from component tristimulus values. Hence, analyses regarding the minimum and the maximum bounds are very important to understand the possible ranges of tristimulus values of subtractive color mixture. In our previous series of articles, several theorems have been proven related to the bounds. In addition to the values, the centroid of a possible range is very important and essential to the prediction of subtractive color mixture. In the present article, several theorems related to the centroid are provided and proven. © 2006 Wiley Periodicals, Inc. Col Res Appl, 31, 418–424, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20247
A new met-enkephalin analogue suppresses plasma vasopressin in man

Abstract Metkephamid acetate, a newly synthesized analogue of methionine enkephalin, suppressed plasma vasopressin levels from 2.4 pg/ml to 0.8 pg/ml after intramuscular administration to 4 normal human volunteers. This suppression occurred in the absence of significant changes in either plasma osmolality or blood pressure. Thus, metkephamid acetate, like many other opiates which bind to the mu subtype of opiate receptors, has a direct suppressive effect on plasma vasopressin levels.
A Garden of Possibilities in Manuchehri’s Spring Panegyrics

The eleventh-century Persian poet Manuchehri Dāmghāni began his career in northern Iran and became established as a leading panegyric poet of the Ghaznavids. The panegyric qasida was a major literary articulation of Persianate cultural hegemony. Most of Manuchehri’s pane-gyric qasidas begin with a nasib about the natural world. The nature description as an introduction to panegyric is an integral part of the panegyric poem and its expression of cultural values, but it is also at odds with the praise section that follows it. This project explores how Manuchehri deploys elaborate rhetoric and imagery in the description of nature to offer a commentary on the possibilities of patronage relationships.
Relation of Morbid Obesity and Female Gender to Risk of Procedural Complications in Patients Undergoing Atrial Fibrillation Ablation

Obese patients with atrial fibrillation (AF) are frequently treated with AF ablation. We sought to examine whether a body mass index (BMI) threshold exists beyond which the odds of experiencing a complication from AF ablation increases. All patients enrolled in the Vanderbilt AF Registry who underwent catheter-based AF ablation from May 1999 to February 2012 were included. Major complications were recorded. Morbid obesity was defined as a BMI >40 kg/m 2 and examined in multivariable analysis. A total of 35 complications (6.8%) occurred in 512 ablations. Morbidly obese patients experienced a greater rate of complications (6 of 42, 14.3%) than the nonmorbidly obese (29 of 470, 6.2%; p = 0.046). Using a discrete BMI cutoff, the odds of complications increased 3.1-fold in those with morbid obesity (odds ratio [OR] 3.1, 95% confidence interval [CI] 1.1 to 8.4, p = 0.03) and 2.1-fold for female gender (OR 2.1, 95% CI 1.04 to 4.38, p = 0.04). With BMI as a continuous variable, the odds of complications increased by 5% per 1 unit increase in BMI (OR 1.05, 95% CI 1.0 to 1.11, p = 0.05), and the increase for female gender was 2.2-fold (OR 2.2, 95% CI 1.1 to 4.6, p = 0.03). In conclusion, morbid obesity represents a BMI threshold above which the odds of complications with AF ablation increase significantly. The increase in complications appears to be driven primarily by events in women, suggesting that morbidly obese women are a special population when considering AF ablation.
Gestational Age- and Growth-Related Alterations in Fetal Right and Left Ventricular Diastolic Filling Patterns

To evaluate the effects of gestational age on left and right ventricular diastolic filling in human fetuses, we retrospectively reviewed the diastolic flow velocity patterns through mitral and tricuspid valves in 307 normal fetuses aged 17 to 39 weeks' gestation. The subjects were divided into 3 age groups; 17 to 24 weeks, 25 to 31 weeks, and 32 to 39 weeks. The variables measured were peak flow velocities of early diastole (peak E wave), of atrial contraction (peak A wave), and the velocity ratio (peak E/A ratio). As a whole, the transmitral peak E wave and peak E/A ratio correlated with age using a second-order polynomial curve fit. The strength of the linear correlation between age and transmitral peak E wave and peak E/A ratio and the slope of the relation were greater in the group aged 32 to 39 weeks than in group aged 25 to 31 weeks. Similar temporal change was observed in the relation between age, transtricuspid peak E wave, and peak E/A ratio. The peak A wave for both atrioventricular valves showed little change with gestational age. Contrary to the accepted concept that fetal peak E wave and peak E/A ratio increases linearly with aging, this study shows that early diastolic filling increases mainly after 25 weeks' gestation. We speculate that the maturational changes in ventricular properties in human fetuses accelerate after midgestation.
Postdivorce Father‐Adolescent Closeness

Research indicates that closeness of the father-child bond following parental divorce is associated with better outcomes for children and adolescents. Unlike other investigations, this study takes a long-term developmental approach to understanding stability and change in postdivorce father-adolescent relationship closeness. Drawing on Add Health data (n = 483), we examine factors that explain (a) why some high-quality father-adolescent relationships remain the same after divorce whereas others decline, and (b) why some low-quality relationships are stable following divorce whereas others improve. High mother-offspring relationship quality and offspring feelings of well-being prevented close father-offspring relationships from deteriorating. Offspring’s childbearing and cohabitation following parental divorce increase closeness in father-offspring relationships that were not close prior to divorce. Although a majority of offspring experienced a decline in closeness following divorce, results from this study show that some very close father-offspring relationships are maintained and some poor relationships become closer.
Caenorhabditis elegans germ line: a model for stem cell biology.

Like many stem cell systems, the Caenorhabditis elegans germ line contains a self-renewing germ cell population that is maintained by a niche. Although the exact cellular mechanism for self-renewal is not yet known, three recent studies shed considerable light on the cell cycle behavior of germ cells, including a support for significant and plastic renewal potential. This review brings together the results of the three recent cell-based studies, places them in the context of previous work, and discusses future perspectives for the field. Developmental Dynamics 236:3343–3357, 2007. © 2007 Wiley-Liss, Inc.
On combined source solutions for bodies with impedance boundary conditions

Numerical solutions to the impedance boundary condition (IBC) combined source integral equation (CSIE) for scattering from impedance spheres are presented. The CSIE formulation is a well-posed alternative to the IBC electric and magnetic field integral equations which can be contaminated by spurious resonant modes. Compared with the IBC combined field integral equation (CFIE), CSIE solutions have the same accuracy when the combined source coupling admittance is chosen to be the same value as the combined field coupling admittance. However, the CSIE formulation is better suited than the CFIE for creating a general purpose computer code capable of handling aperture radiation problems and/or a scatterer which has a spatially varying surface impedance.
Analysis of linear time-varying circuits by the Brillouin-Wentzel-Kramers method

This paper presents a general mathematical technique for studying the response of linear time-varying circuits that contain parameters whose magnitudes vary in a periodic manner with the time. The method presented is based on the Brillouin-Wentzel-Kramers (BWK) procedure, which has been widely used in connection with problems of wave mechanics. This method gives approximate results with very little error if the variable circuit elements exhibit small variations about a large average value. The application of the method to circuit problems is illustrated by using it to study the free and forced oscillations of typical series circuits that contain periodic capacitance, resistance, and inductance parameters.
Inducing compressive residual stress in microscale print-lines for flexible electronics

Abstract Printed electronics are becoming widespread in modern industrial devices. In many of the manufacturing processes of printed electronics, one step is the deposition of initially molten (or liquid), microscale, “print-lines” of material onto a flexible substrate. As the deposited molten print-line solidifies, the bonded print-line and substrate may have the tendency to curl (attain a finite curvature), due to the differences in the thermal expansion coefficients, elastic properties, etc. The quality and durability of the solidified print-line (which is mechanically-weak) is adversely affected by residual tensile stress states. Tensile stress states have a tendency to induce damage in the form of cavities or cracks in the deposited material, which would hinder the printed electronics operation. Therefore, ideally, one would like the solidified print-line to be in a state of compression. Inducing a compressive stress-state in the print-line is particularly important in the vicinity of the substrate interface, since damage in that location may also initiate delamination of the deposited material and, eventually, a malfunction of the intended printed electronics application. In this work, employing an elementary thermo-mechanical model, a mathematical expression is derived for the combination of system parameters needed to ensure that the print-line material at remains in a compressive state at the bimaterial interface.
INFLAMMATION FAILS TO EXPLAIN YOUNG-OLD DIFFERENCE IN HYPEROXIA LETHALITY

AbstractThe inflammation that accompanies oxygen toxicity to the lung is believed to magnify the damage and to be a significant factor in determining the ultimate extent of lung injury. The mechanism proposed for the increased lung damage associated with inflammation is the release of reactive oxygen species by leukocytes (PMNs) and macrophages that are recruited to the damaged lung. In an earlier study, when 2-mo and 27-mo male Fischer 344 rats were exposed to >98% oxygen, a significant difference was found in survival. The old rats lived approximately two times as long as the young rats. This study explored the hypothesis that the age-related lethality difference was due to a faster onset and greater extent of inflammation in the lungs of young rats than old. Following 55 h of exposure to >98% oxygen, bronchopulmonary lavage demonstrated no differences in protein or in neutrophil or macrophage composition. In addition, there was no significant difference in whole lung myeloperoxidase activity between th...
AN INVESTIGATION OF THE ROLE OF EDUCATIONAL BACKGROUND ON PERFORMANCE ON THE GRE® ANALYTICAL MEASURE

There have been a number of reports that educational background is related to performance on reasoning problems similar to those used on the GRE analytical measure. The purpose of this research was to evaluate whether educational background as defined by broad undergraduate major fields was related to differential difficulty for specific items on the GRE analytical measure. An index of differential difficulty, MH-DDIF, was calculated for the reasoning items from 13 GRE forms. We found only low to moderate levels of MH-DDIF for the two item types on the analytical measure. A higher proportion of logical reasoning items than analytical reasoning items had moderate MH-DDIF. The relationship of item classification attributes to MH-DDIF was evaluated. In addition, other attributes potentially related to MH-DDIF for logical reasoning items were identified and their ability to predict MH-DDIF was evaluated with a cross-validation design. The attributes identified as potentially related to MH-DDIF for items from one subset of GRE forms did not predict MH-DDIF for items in a second subset. Thus, a strong link between item performance and educational background was not observed within item types. Because of the failure to cross-validate the potential predictors of DIF, other factors that contribute to MH-DDIF are briefly considered. The relationship of these results to other research on the effect of educational background is discussed. We also discuss implications for test design and how test development practices are effective in minimizing the impact of educational background within item types.
Bone Responsiveness to Parathyroid Hormone in Normal and Osteoporotic Postmenopausal Women

Increased bone loss in estrogen-deficient normal and osteoporotic postmenopausal women may be due mainly to increased sensitivity of bone-resorbing cells to circulating PTH, but this is supported only by indirect data. Therefore, we tested the responsiveness of bone to PTH directly by using a 3-day iv infusion of bovine PTH-(l–34) at 400 U/day in 9 normal premenopausal women, 10 normal postmenopausal women, and 12 osteoporotic postmenopausal women. Serum calcium and urinary hydroxyproline concentrations increased (P < 0.001) over baseline values during infusion, but the mean increases in both variables did not differ among groups. The data do not support the hypothesis that estrogen deficiency increases the sensitivity of bone to PTH or that the sensitivity in osteoporotic women is greater than that in normal postmenopausal women. Within the constraints imposed by the method of testing, we conclude that the additional bone resorption induced by menopause and by osteoporosis may be due to mechanisms that a...
Motor performance and sensory-evoked potentials.

Abstract Averaged evoked potentials (EP) to tones were determined for fifteen subjects in three tasks which were designed to evaluate the effects of motor response, of withholding a response and of different response latencies. With the influence of eye movement minimized, it was found that the various deflections of the sensory EPs were affected differently as follows: 1.1. Withholding a response produced a significantly larger P 3 deflection. The amplitude of this deflection was negatively correlated with reaction time (RT). 2.2. Stimuli to which overt motor responses were subsequently made produced a negative shift in deflections N 1 , P 2 and N 2 , but there were no significant changes in deflections P 1 , P 3 and N 3 . 3.3. No effects which could be ascribed to specific time characteristics of the tasks (e.g., simple versus choice RT) were found and no effects could be attributed to the overt motor response or its immediately preceding EMG activity. The data were interpreted to mean that the negative shift in N 1 , P 2 and N 2 is related to the development of an excitatory state associated with the intention to respond to the stimulus and that increased positivity in P 3 is uniquely related to the act of withholding a response to the stimulus when rapid action is required. No effects on the averaged EP were observed that could be attributed unequivocally to occurrence of overt motor response itself.
A method for measuring infrared reflection—Absorption spectra of molecules adsorbed on low-area surfaces at monolayer and submonolayer concentrations

Abstract Instrumentation has now been developed for the measurement of infrared reflection-absorption spectra (IRRAS); this is a very sensitive technique which can easily detect the vibrational spectra of many adsorbates at submonolayer concentrations on low-area surfaces. Furthermore, being a photons-in photons-out technique, it is capable of being applied in the presence of adsorbant molecules in the gas phase at pressures in the range 10−11–102 Torr and with substrate temperatures ranging from 77 to 1200 K. These features of the technique make it ideally suited to the study of surface species present during actual catalytic reactions. Details of the design and operation of an IRRAS spectrometer are described.
Life history and male intertroop mobility among Japanese macaques (Macaca fuscata)

Male intertroop transfer among Japanese macaques (Macaca fuscata) often coincides with the mating season. However, no necessary connection exists between mating by newly arrived males and whether they join a troop—visitors often mate, and males that join troops may show little mating success. On the other hand, intertroop transfer often coincides with major events in the developmental and social life history of males, such as the attainment of sexual maturity and full adult body size or rise in dominance rank. Thus, intertroop transfer may reflect age-specific behavioral patterns in which males maintain a position in the age-rank structure of troops, where the rank acquired in a new troop is partially determined by age.
Griseofulvin: Interaction with normal and subtilisin‐treated tubulin

Griseofulvin, an antifungal drug, possesses antimitotic activity by inhibiting microtubule assembly. The interaction of griseofulvin with tubulin is unique in that it increases the sulfhydryl titer of tubulin without affecting the hydrophobic areas. Because the C-terminal regions of both α- and β-tubulin influence the conformational and the drug-binding properties of tubulin, we decided to study the interaction of griseofulvin with αβ tubulin and tubulin treated with subtilisin to selectively remove the C-terminal regions from both the α- and β-subunits (αsβs). We found that the apparent Kd of griseofulvin for αsβs tubulin (83 μM) was virtually unaltered compared to its Kd for αβ tubulin (91 μM) as determined by the tryptophan fluorescence quenching assay. The increment of the sulfhydryl titer (0.47 mol/mol) by griseofulvin was not affected by removing the C-termini from the α- and β-subunits. Moreover, the lack of effect of griseofulvin on the hydrophobic areas was not changed after the cleavage of the C-termini of the α- and β-subunits. These data therefore strongly suggest that griseofulvin binds at a certain region of tubulin distant from the C-terminal domains of the α- and β-subunits and that the C-terminal domains of both subunits do not have any conformational influence over the binding site of griseofulvin. Determining the binding site of griseofulvin will help in understanding its role in regulating microtubule assembly and dynamics. Drug Dev. Res. 53:44–49, 2001. © 2001 Wiley-Liss, Inc.
The Prognostic Value of Loculations in Parapneumonic Pleural Effusions

Forty-eight patients with pleural effusions who had sonographically directed thoracocentesis were evaluated retrospectively for radiologic findings, pleural fluid chemistries, and outcome. Loculation was found to be a radiologic marker of diagnostic and prognostic significance. The presence of loculations correlated with exudative pleural fluid chemistries, but no radiologic finding was specific for empyema. "Extreme" pleural fluid chemistries were associated with loculation, but not with empyema. Patients with loculated effusions had larger effusions, longer hospitalizations, and more frequent tube thoracostomy procedures than patients with nonloculated effusions. Light's criteria for tube thoracostomy were found to be unreliable in patients with loculated parapneumonic effusions or in patients treated with prolonged antibiotic therapy prior to thoracocentesis.
A Cerenkov microlaser

A Cerenkov microlaser (CML) is proposed. The device uses an electron beam and a semiconducting-film-loaded open, quasi-optical resonator to produce coherent, electromagnetic radiation at submillimeter and far-infrared wavelengths. General expressions for the tuning, gain, and constraints due to beam quality are used, together with optical and material considerations to establish operating characteristics. >
Characterization of defect structures in Lely 6H-SiC single crystals using synchrotron white beam x-ray topography

Defect structures in Lely SiC single crystals have been studied using synchrotron white beam X-ray topography. Basal plane dislocations and stacking faults probably generated during post-growth cooling are clearly revealed. For both perfect dislocations and partial dislocations bounding the stacking faults, Burgers vectors and line directions are determined from contrast extinction analysis as well as projected direction analysis on different topographic images. The fault planes and fault vectors of the stacking faults were determined using contrast extinction analysis. Possible dislocation generation mechanisms are briefly discussed.
The origin of higher taxa: macroevolutionary processes, and the case of the mammals

The origin of a new higher taxon is characterized by a long-term phylogenetic trend, involving evolutionary changes in a large number of characters. At this phylogenetic level, the conflict between internal integration of the phenotype and its evolvability can be resolved by the correlated progression model, in which many disparate traits evolve by a sequence of small increments in loose correlation with one another, rather than by the modularity model. The trend leading to the new higher taxon implies the existence of a long ridge in an adaptive landscape. An evolutionary lineage tracking it requires adaptive changes in broad biological characteristics, involving many traits. Species selection is a possible additional driver of the trend. These conclusions are tested against the synapsid fossil record of the origin of mammals. The reconstructed sequence of acquisition of mammalian traits supports the correlated progression model. The adaptive ridge involved is postulated to have been a sequence of overlapping niches requiring increasing ability to remain active in daily and seasonally fluctuating environments by means of increasing internal regulation. An inferred speciation bias in favour of relatively small, relatively more progressive carnivores indicates that species selection was also involved in driving the trend. Palaeoenvironmental evidence indicates that ecological opportunity probably played a role at certain points along the lineage.
Rethinking Climate Change Governance and Its Relationship to the World Trading System

International climate negotiations have thus far eschewed efforts to incorporate trade restrictions, but they have also failed to achieve their objective of reducing global emissions. Because of this failure, some countries are now inclined to act unilaterally and minilaterally, in many cases by imposing trade restrictions against third parties. Such actions are likely to invite retaliation. They could even ignite an escalating trade war. The best way to avoid such conflicts is not to limit the use of trade restrictions, but to make international climate negotiations effective. Ironically, success in addressing climate change multilaterally may require incorporating trade restrictions in a new kind of climate agreement. Trade restrictions have been used successfully in other international agreements. But in these agreements, the primary purpose of the restrictions has been to encourage participation. That is, their primary purpose has been to enforce the agreement. This is the role trade restrictions ought to play in a new climate treaty. But for them to play this role, the design of climate treaties must change. If climate treaties are designed strategically, the threat to restrict trade will suffice to enforce the agreement; and if the threat to restrict trade is credible, and the punishment associated with the restriction severe, trade restrictions will not actually have to be used. By incorporating trade restrictions in this way, greenhouse gas emissions can be reduced without putting at risk the gains from multilateral cooperation in trade.
Exploring the Excited States of Vacancy Defects in Silica

A study of vacancy defect formation is carried out using a density functional theory molecular dynamics simulation methodology. The objective is to study the effects of electronic excitations in crystalline and non-crystalline silica polymorphs. We present an initial study focusing on the formation energetics of distinct oxygen vacancy defect states in α-quartz.
Lactic Acid Bacteria and Human Health

Although claims for health and nutritional benefits have been made for lactic acid bacteria in fermented dairy products for nearly a century, the nutritional and therapeutic value of these organisms is still controversial. This article will review the scientific basis of these claims. There are numerous studies showing fermentation of food with lactobacilli increase the quantity, availability, digestibility, and assimilability of nutrients. The basis for this conclusion comes from direct measurements of vitamin synthesis and from increased feed efficiency when fermented products are fed to animals. There have been a number of studies showing that various fermented dairy products lower serum cholesterol levels in humans and animals. These studies are reviewed and the validity of these findings are assessed. A summary of the evidence indicating that lactase deficient individuals can eat yogurt and the mechanisms involved in this toleration is reviewed. The role of fermented dairy products in inhibiting tumor growth and chemically induced tumors in animals is discussed and the possible mechanisms involved in this protective effect are reviewed. Fermented dairy products and lypholized lactobacilli preparations have been shown to be useful in treating and preventing various intestinal infections including; salmonellosis, shigellosis and antibiotic induced diarrhea. In this context a specific lactobacillus designated GG has been shown to be useful in treating recurring diarrhea caused by a toxin produced by Clostridium difficile.
Scheduling many-task workloads on supercomputers: Dealing with trailing tasks

In order for many-task applications to be attractive candidates for running on high-end supercomputers, they must be able to benefit from the additional compute, I/O, and communication performance provided by high-end HPC hardware relative to clusters, grids, or clouds. Typically this means that the application should use the HPC resource in such a way that it can reduce time to solution beyond what is possible otherwise. Furthermore, it is necessary to make efficient use of the computational resources, achieving high levels of utilization. Satisfying these twin goals is not trivial, because while the parallelism in many task computations can vary over time, on many large machines the allocation policy requires that worker CPUs be provisioned and also relinquished in large blocks rather than individually. This paper discusses the problem in detail, explaining and characterizing the trade-off between utilization and time to solution under the allocation policies of Blue Gene/P Intrepid at Argonne National Laboratory. We propose and test two strategies to improve this trade-off: scheduling tasks in order of longest to shortest (applicable only if task runtimes are predictable) and downsizing allocations when utilization drops below some threshold. We show that both strategies are effective under different conditions.