cssi/SciSciGPT-SciSciNet huggingface dataset:
Characterization of impurities and defects in InSb and HgCdTe using novel magneto-optical techniques

Detection and identification of impurities and defects in semiconductor materials has long been a topic of technological importance. Of particular interest is the activation energy of the impurity/defect states. For narrow-gap materials magneto-optics is a technique of choice, since resonant transitions from impurity-to-band or band-to-impurity states allow for the precise determination of just these states. Two magneto-optical techniques, resonant magneto-optical and resonant impact ionization spectroscopy, have been successfully used to investigate intrinsic magnetoabsorption and shallow and deep impurity and defect levels in bulk InSb and in bulk and liquid-phase-epitaxy HgCdTe. In this paper, these magneto-optical techniques will be reviewed, concentrating on their versatility and sensitivity for the detection and identification of weak absorption process such as those expected when impurity and defect levels are involved. A discussion of the mechanisms and results for a variety of magneto- optical phenomena from both InSb and HgCdTe will be given and discussed.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Iron isotope fractionation in the Earth’s lower mantle

The two main iron-bearing silicate phases in the mantle—ferroperovskite and ferropericlase—are expected to partition iron isotopes differently. Theoretical calculations suggest that the spin state of iron strongly influences the iron isotopic composition of ferropericlase, whereas the iron isotopic composition of ferroperovskite is almost independent of spin state.
Gait Characteristics in Nondisabled Community-Residing Nonagenarians

Abstract Kristhnamurthy M, Verghese J. Gait characteristics in nondisabled community-residing nonagenarians. Objective To determine gait performance in community-residing nonagenarians. Design Nested case-control study. Setting Community. Participants Thirty-one nondisabled nonagenarians (17 women) and 170 young-old controls (age range, 70−85y) participating in a longitudinal study. Interventions Not applicable. Main Outcome Measures Systematic clinical and quantitative gait assessments. We also examined the association of gait velocity with death over a 1-year period. Results Nonagenarian men had better performance on all quantitative gait parameters examined compared with women. Male sex (β=.58; 95% confidence interval [CI], 9.95−38.89) and depressive symptoms (β=−.34; 95% CI, −6.73 to −0.04) were independently associated with gait velocity in multivariate linear regression models. The 6 hypertensive nonagenarians on angiotensin-converting enzyme (ACE) inhibitors had faster gait velocity (median, 103.1cm/s) compared with the 8 hypertensive nonagenarians not on ACE inhibitors (median, 77.5cm/s; P =.029). Nonagenarians had worse quantitative gait parameters compared with the young-old controls, although the differences were less marked when subjects with clinically normal gaits in both groups were compared. Gait velocity did not predict survival over 1-year follow-up. Conclusions Gait characteristics in nondisabled community-residing nonagenarians are associated with male sex, depressive symptoms, and medications. The quantitative gait measures in this sample of nondisabled nonagenarians provide a yardstick to compare younger-age groups.
A rare complication of myocardial infarction

A 75-year-old patient was admitted with lightheadedness and feeling unwell for 5 days. He had no significant past cardiac history, and denied any chest pain or breathlessness. Electrocardiogram showed q waves with residual ST elevation in the inferior leads (Panel A figure 1). On examination, the patient was haemodynamically stable, but profoundly hypoxic with oxygen saturations of 67% …
The relationship between 13, 14-dihydro-15-keto PGF2α and LH secretion in bulls

Half-life (t12), volume of distribution (Vd)_and total body clearance (TBC) of 13, 14-dihydro-15-keto PGF2α (PGFM) were measured in order to determine optimal sampling frequency for accurate measurement of PGFM. Three yearling Holstein bulls (349.2 ± 6.7 kg) and 3 yearling Holstein steers (346.7 ± 7.0 kg) were utilized in a 3 × 3 Latin square design. Animals were given 0, 25 or 50 μg PGF2α I.V.; blood samples collected every 2 min and plasma PGFM determined. The t12, Vd and TBC of PGFM were 2.3 ± .2 min, 43.3 ± 3.3 liters and 13.7 ± 1.9 liters/min, respectively and were similar for 25 and 50 μg doses. To determine the relationship between endogenous PGFM and LH secretion in bulls, blood samples were collected every 2 min for 12 h in 4 yearling Angus bulls (489.1 ± 11.6 kg). All animals elicited at least one LH surge and PGFM concentrations were measured in samples coincident with the LH surge. Mean plasma PGFM concentrations were greater prior to the LH surge than during the LH surge. In addition, mean plasma PGFM concentration and frequency of PGFM peaks appeared to increase prior to the LH surge suggesting an association between PGFM and pulsatile LH secretion in the bull.
The restricted effects of right-hemisphere lesions after age one; Wechsler test data.

Abstract The late effects of early and later lateralized brain lesions were studied with the Wechsler intelligence test in 50 patients with unilateral nonprogressive cerebral lesions incurred in infancy or in childhood. Results differed according to age at lesion for right but not left hemisphere patients; patients with right hemisphere lesions after age one had normal Verbal ratings impaired Performance ratings; patients with earlier right hemisphere lesions were impaired on both ratings.
A Simple Technique for Multiple-Parameter Pattern Recognition with an Example of Locating Fronts in Model Output

Abstract A statistical pattern recognition technique called IREW is described. IREW has several strengths, such as fast execution, small storage requirements, and increments learning, that may make the technique useful for many meteorological pattern recognition problems. A weakness of IREW is that it may not recognize complex patterns as well as more sophisticated pattern recognition techniques do. IREW analyzes data by using a derivative of Bayes' rule to multiplicatively combine the influence of predictors. The weight assigned to each predictor is determined empirically from a training dataset containing the data and verifications for multiple cases. IREW uses several methods to select useful subsets of a large set of predictors. The objective identification of surface fronts in Nested Grid Model forecasts is described to illustrate how IREW can be applied to a typical pattern recognition problem. The work consisted of identifying factors related to fronts and using some of those factors to make analys...
The fundamental construction for 3-designs

Abstract We discuss a generalization of Wilson's fundamental construction for group divisible designs which is intended to produce 3-wise balanced designs, rather than pairwise balanced designs. The construction generalizes many known recursive constructions for Steiner quadruple systems and other related designs. The generalization of Wilson's construction is based on a structure which is a 3-design analogue of a group divisible design. We show that other such analogues which have appeared in the literature are special cases of our definition. We also give several new applications of these structures.
The uptake of chemical elements from coal ash and settling basin effluent by primary producers II. Relation between concentrations in ash deposits and tissues of grasses growing on the ash

Abstract A number of reports of biomagnification of trace metals by plants indicate that elements are selectively concentrated within certain tissues when plants grow on coal ash. This study determined the uptake by, and tissue bioaccumulation of, 15 chemical elements within broom sedge and nut grass growing in the drainage system of a coal ash basin. Biomagnification of these elements by the grasses was compared to concentrations of these elements found in duckweed within the same system. Aluminium, arsenic, barium, cadmium, cobalt, chromium, copper, iron, mercury, manganese, molybdenum, selenium, strontium, titanium, and zinc were measured by neutron activation analysis in roots, stems, leaves and fruit of the grasses which grew in sediments within the effluent. Mercury and zinc were biomagnified in both grasses and duckweed to a level exceeding the concentration in sediment. All elements were biomagnified above the water concentration in all parts of the plants. Bioaccumulation of elements in the leaves and fruit of these plants provides a concentrated source of potentially toxic chemical elements for passage to animals which may consume these plants. The mechanisms of movement of potentially toxic elements from coal ash or water into food webs need additional study as utilization of coal is increased.
A personality scale of manifest anxiety.

Since the Taylor Manifest Anxiety Scale has proven to be such a useful device in the selection of subjects for experimental purposes, a description of the construction of the test and the normative data that have been accumulated in connection with it are presented as of possible interest to other i
Subglottic Tracheal Resection

The most common indication for tracheal resection is stenosis secondary to cuff injury from either tracheostomy tube or endotracheal tube or tracheostomy stoma1 injury. These injuries occur in the upper, middle, or distal trachea and are amenable to resection and reconstruction with excellent results. Techniques have been devised to allow resection of up to one half of the adult trachea. When postintubation stenosis and other inflammatory processes extend from the upper trachea into the subglottic larynx, the problem becomes more complex. If the lesion extends well above the lower border of the cricoid cartilage, circumferential resection is not possible because of the entry location of the recurrent laryngeal nerves into the larynx medial and posterior to the inferior cornua of the thyroid cartilage along the back of the posterior cricoid lamina (Figure I). The stenosis may involve only the anterolateral portion of the cricoid. When circumferential stenosis exists involving the posterior cricoid plate as well, the problem is much more formidable. The closer the stenosis comes to involving the vocal cords, the less suitable it is for resection, reconstruction, and preservation of laryngeal function.
Variations in watch keeping performance as a function of the rate and duration of visual signals

This study was designed to assess the relative effects on watch keeping performance of five signal durations (0.5, 1.0, 2.0, 4.0, and 8.0sec) combined factorially with five signal rates (6, 12, 24, 48, and 96 sig/h). A visual display consisting of a red and green light mounted on a vertical vector was used; red-onset and green-offset were critical signals. The probability of correct detections increased monotonically with increases in signal duration; a stable rate of nearly 100% detection was approached at signal durations of 4.0 and 8.0 sec, independently of signal rates. The likelihood of detection was enhanced by increases in signal rates only at the 0.5-sec duration with the green-offset critical signal. Response time to correct detections increased with time on watch, independently of signal rates and durations.
Aeroelastic tailoring - Creative uses of unusual materials

This paper discusses the fundamental aspects of the use of aeroelastic tailoring to enhance the performance of flexible fixed wing aircraft. Tailoring with advanced composites is seen as part of a natural evolutionary process in the everchanging field of design. Among topics discussed are: static divergence; lift effectiveness; drag reduction; control effectiveness; and, vibration and flutter. In addition, terminology is reviewed, together with descriptive formulas that characterize stiffness coupled structures. Finally, a summary of design features favorable to different facets of aeroelastic tailoring is given to illustrate conflicts and compromises that must be considered.
Spotlight on CD8 T cells in MS

IMMUNOBIOLOGY Multiple sclerosis (MS) involves an autoimmune response directed against central nervous system (CNS) myelin antigens. The histologic features involving both lymphocyte and macrophage infiltration into the CNS, the role of interferon gamma (IFN-γ) in causing disease exacerbations,
Computer supported collaborative learning for curriculum integration

Abstract Computer supported collaborative learning (CSCL) has the potential for significantly improving undergraduate education. However, there are many challenges for institutions, instructors and students in achieving effective collaboration that actually improves learning. Two of the most critical are achieving teacher buy-in and motivating students to participate in a knowledge-building community. We have developed a new CSCL tool whose flexibility is inspiring good teachers to create exciting new collaborative learning activities, and whose persistence is an enticement to students. We are now attempting to use this tool to leverage a particular kind of educational reform goal: achieving integration across curricular boundaries.
Nonpenetrating traumatic complete heart block and myocardial infarction with normal coronaries: A case report with review of the literature

A case of transient complete heart block and lateral wall myocardial infarction secondary to nonpenetrating chest trauma is presented. Lack of any associated cardiac lesions is an interesting feature of this case report. Proposed criteria for heart block secondary to trauma and difficulty in making the diagnosis of myocardial infarction secondary to trauma due to lack of appropriate “gold standard” are discussed.
Exit jet particle velocity in the in vivo canine laryngeal model with variable nerve stimulation

Summary This study extends previous work on exit jet particle velocity in the in vivo canine model of phonation by measuring air particle velocity at multiple locations in the midline of the glottis and across multiple levels of recurrent laryngeal nerve (RLN) and superior laryngeal nerve (SLN) stimulation. In a second experiment, exit jet particle velocity was measured at midline and offmidline positions with constant levels of RLN and SLN stimulation. In this study, peak particle velocity was higher at the anterior commissure than at the posterior commissure in the midline of the glottis, and peak particle velocity was higher at the midline than at offmidline positions. In addition, increasing levels of RLN stimulation resulted in increasing peak particle velocity; however, increasing levels of SLN stimulation failed to produce a uniform effect on peak particle velocity.
Gas liquid chromatographic analysis of sphingosine bases in sphingolipids of human normal and multiple sclerosis cerebral white matter

Sphingomyelins, cerebrosides and sulfatides were isolated from white matter of human normal and multiple sclerotic brain. Column chromatography was used for class separations, which were monitored by thin layer chromatography. Acid-catalyzed methanolysis, followed by isolation of bases and gas liquid chromatography of periodate-produced aldehydes, was used to determine sphingosine base composition of each sphingolipid. Reflux methanolysis (where HCl=2 N) was used for cerebrosides and sulfatides, but could not be used for reliable sphingomyelin base analysis, for which sealed-tube methanolysis at 70–80 C (where HCl=1 N) was used. Our results suggest there is little, if any, difference in sphingosine base chain-length distribution among the sphingolipids analyzed.
Driven modulation instability and new class of solitons of incoherent light

We present experimental results on induced (driven) modulation instability and associated pattern formation of partially spatially incoherent light. Incoherent modulation instability (MI) is driven by seeding noise through cross-phase-modulation rather than intrinsic noise in a noninstantaneous nonlinear medium. We show that a threshold exists for such driven incoherent MI to occur, which depends on the degree of spatial coherence as well as the strength of the nonlinearity. Above the threshold, the MI leads to formation of ordered and disordered patterns of incoherent light. New class of solitons of incoherent light observed by suppressing incoherent MI will also be reported.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Survey of graduate programs in medical information science in the United States

A survey of graduate programs in Medical Information Science in the United States was conducted in 1989. The survey identified four types of programs which provide opportunities for graduate students to concentrate their education and research in the field. Thirteen programs were identified and described.This paper summarizes the survey results and presents program descriptive information.
Radar Backscattering by Inhomogeneous Precipitation Particles

Abstract Calculations of radar backscattering by inhomogeneous precipitation particles require values of the dielectric function of two-component mixtures. Four such dielectric functions are critically examined and their relative merits are weighed. Although apparently different, two are shown to be equivalent: the effective-medium and Polder-van Santen theories. All the dielectric functions agree when the two components are dielectrically similar. All except the Maxwell-Garnet dielectric function are symmetric with respect to interchange of the components. When compared with measurements on ice-air mixtures, the effective-medium and Maxwell-Garnet dielectric functions are marginally better than the Debye function, which has previously been used in backscattering calculations. When the fraction of water is high, the effective-medium function gives calculated values of radar backscattering that are in good agreement with measurements on ice spheres coated with a mixture of ice and water. The Maxwell-Garnet...
Effect of topical pergolide on aqueous dynamics in normal and glaucomatous monkeys.

The effects of pergolide mesylate, an ergoline derivative, were studied on intraocular pressure (IOP), outflow facility, aqueous humor flow, and pupil size in monkeys. Unilateral topical administration of two 20-μl drops of 0·1% pergolide significantly lowered IOP in the treated- and contralateral eye in both normal- and glaucomatous monkeys. In 12 normal monkeys, the baseline IOP of 18·3 ± 0·4 mmHg [mean ± s.e.(m.) ] was maximally reduced to 14·4 ± 0·7 mmHg in the treated eye ( P P s.e.(m.) ] in the treated eyes and 31·7 ± 3·3 mmHg in the untreated eyes maximally decreased to 23·9 ± 2·2 mmHg ( P P P > 0·7) in outflow facility occurred in either eye of 11 normal monkeys 2 hr after unilateral 0·1% pergolide treatment. In six normal monkeys, the baseline aqueous humor flow of 1·58 ± 0·20 μl min −1 in treated eyes and 1·44 ± 0·18 μl min −1 in untreated eyes was reduced to 0·92 ± 0·08 μl min −1 ( P −1 ( P > 0·10), respectively, from 0·5- to 3·5 hr after drug administration. A mydriatic response was observed in both eyes after unilateral treatment from 1- to 2 hr in eight normal monkeys. By the third day of treatment, bilateral twice a day 0·1% pergolide drops in eight glaucomatous monkey eyes no longer significantly ( P > 0·05) decreased IOP.
DDT: A New Hypothesis of Its Mode of Action

It is suggested that DDT and perhaps other chlorinated hydrocarbon insecticides owe their activity to the formation of a charge-transfer complex with a component of the nerve axon, with consequent disturbance of function. Experimental evidence is provided for the formation of two complexes with components of cockroach nerve; the complexes have been partially purified. Their formation is accompanied by an absorption in the 245- to 270-millimicron range.
Secondary hydrogen-bonding effects on the nuclear magnetic shielding of the hydrogen nuclei in ice: An ab initio quantum-mechanical study

Abstract The chemical shift anisotropy and the isotropic magnetic shielding constant of the hydrogen nuclei in the (H 2 O) 2 , (H 2 O) 3 , (H 2 O) 2 and H 2 O systems have been calculated using ab initio quantum-mechanical techniques. The results show that secondary hydrogen bonding has a significant effect on these two parameters.
Table of the Percentage Points of the Trivariate t-Distribution with an Application to Uniform Confidence Bands

Tables of the percentage points of the trivariate t-distribution are presented. The tables presented consider the situation when the coordinates are not necessarily equal. In addition percentage points are presented for a fairly large selection of possible correlation structures. Also given are several practical situations where these tables could be used. Emphasized is the use of these tables in obtaining a uniform confidence band for the quadratic model where the associated probability is approximate.
Sedimentation of biogenic matter in the deep ocean

The major constituents of biogenic particles that settle through the water column of the ocean are carbonate tests, opaline shells, and particulate organic matter (cellular and amorphous). This paper describes the quality and quantity of such fluxes to the deep ocean and compares them with biogenic remains in the bottom sediment. Studies of samples collected during PARFLUX sediment trap experiments in the Atlantic and Pacific have shown that 60 to 90% of the total particulate flux is of biogenic origin; the contribution of biogenic materials decreases with increasing depth. Carbonate hard parts accounted for 30 to 60% and were the largest constituents in pelagic sediments at temperate and tropical areas. Combustible components ranged from 10 to 30% with zooplankton remains and fecal pellets accounting for the bulk of the organic flux. Amorphous fine particles were also significant in the organic flux. The atomic ratios of organic constituents in settling particles deviated systematically from the ‘Redfield ratio’ of 106:16:1 (C:N:P) for marine plankton. In the mesopelagic depths the ratio was 200:21:1, and in the bathypelagic depths the ratio was 300:33:1, with a wide range of variation in phosphorus. The residence time of biogenic particles in the deep-ocean water columns is relatively short and the particles can be expected to arrive at the abyssal floor without major dissolution and remineralization (excepting small opal particles). Fine organic particles such as cell remains and pigmented granules are a major source of organic carbon and nitrogen at deep traps. Microscopic study suggests that the fine organic particles were once included in larger but loosely-formed particles that settled rapidly. Such particles dispersed from settling fecal pellets or similar particles are reintroduced into the water column resulting in ‘secondary’ suspended particles. Such particles may eventually be remineralized while in suspension. The decomposition rate of organic carbon in the deep water was estimated to be about 2.2 mg C m−2 day−1, a rate consistent with rates of oxygen consumption estimated by other investigators. The bottom sediment is enriched in refractory lithogenic particles because of the remineralization of biogenic matter. A hypothetical benthic transition layer serves as a reservoir of benthic activity and can exist under certain conditions at the abyssal floor.
Fluorine K x-ray spectra for projectiles moving at 0.5 to 1.5 MeV/amu in gas, foil, and solid targets

High-resolution x-ray spectral measurements are used to determine the relative intensity of x-ray transitions for ions such as fluorine excited in collisions with various-pressure Ne, Ar, and Kr gas targets, thin carbon foils, and a thick carbon slab. The relative intensities are observed to be nonlinearly dependent on both target density and incident charge $Z$. These effects are attributed to strong collisional quenching of initial states by subsequent large-impact-parameter collisions. The data permit extraction of the total quenching cross sections (${\ensuremath{\sigma}}_{Q}$) for fast fluorine ions in various states. A strong enhancement of the relative intensity of $2^{3}P_{1}$ is observed for ${\mathrm{F}}^{7+}$ and ${\mathrm{O}}^{6+}$ projectiles. This strong enhancement is attributed to selective excitation of metastable states in the beam, i.e., $1s2s^{3}S_{1}$, into the $1s2p^{3}P_{1}$ state. Finally, the data for foil and solid targets are used to obtain information on the excitation states of ions moving in solids.
Influence of scCO2 Injection on Precipitation and Metals Migration, and Changes in Electrical Resistivity☆

Laboratory experiments showed that low viscosity scCO2 displacement of the brine into Mt Simon Sandstone and Eau Clair formation cores (FutureGen 2.0 Geologic Sequestration site, Jacksonville, Illinois, USA) was slow by advection, as scCO2 travels predominantly in larger pores, leaving significant brine in smaller pores. As the scCO2 displaces the brine in larger pores and carbonate partitions into the brine, the resulting acidification (pH 3 to 4) causes short-term mineral dissolution, ion desorption, and iron oxide particulate movement. Major aqueous biogeochemical changes observed over 1.2 years from core/brine/scCO2 interactions includes: a) significant increase in Mg2+, K+, and SO4 concentrations (10s to 100s of mmol/L), b) dissolution of the hematite coating on the quartz grains, c) significant precipitation of NaCl and KCl, and d) some anaerobic microbial growth. Electron microprobe analysis showed the formation of some NaCl and KCl, but precipitates were too small a volume to significantly change permeability. Anaerobic microbial growth correlated with scCO2 (23.5x in 1300h), was also too small to influence permeability. Iron oxide particulate movement was observed as a result of scCO2 injection (acidification), but results could not conclusively correlate with formation permeability change. The electrical resistivity change of the rock core from 100% brine to 100% scCO2 was in the expected range (3x to 5x), with most of the change observed between 70% to 100% scCO2. Field scale conditions simulated using these laboratory-measured electrical resistivity changes indicated insufficient resolution was likely at the field site using surface electrodes due to the depth of injection (1200 m). Overall, injection of scCO2 into the brine-filled Mt Simon sandstone cores resulted in small geochemical and microbial changes over the short-term (< 1.5 years) with some iron oxide particulate movement.
Effect of food type on the acute and chronic toxicity of copper to Daphnia magna

SUMMARY. Daphnia magna was maintained on two diets and exposed to acute and chronic copper stresses. Animals fed vitamin-enriched algae were less sensitive to a chronic copper stress than animals fed a trout-granule diet. This conclusion is based on the responses of cohorts as measured by survival, mean brood size and r, the instantaneous rate of population growth. Application factors were also significantly different for animals reared on the two foods (0.47 for algal-fed animals, 0.12 for animals reared on trout-granules). In contrast to chronic toxicity, 72 h LC50 values were not significantly different for animals maintained on the two foods. This suggests that the mechanism of toxic action is different for acute and chronic toxicity and that, if so, the ratio between chronic and acute toxicity would not be a constant under different environmental conditions.
Aminoguanidine reduces glomerular inducible nitric oxide synthase (iNOS) and transforming growth factor-beta 1 (TGF-β1) mRNA expression and diminishes glomerulosclerosis in NZB/W F1 mice

Over-expression of iNOS is implicated in the pathogenesis of glomerulonephritis in animal models of systemic lupus erythematosus. The aim of this study was to evaluate the effect of aminoguanidine, a selective inhibitor of iNOS, for the protection from glomerulosclerosis in NZB/W F1 mice. Female NZB/W F1 mice (n = 8) were treated with aminoguanidine (1 g/l) in drinking water for 4 months starting at age 2 months before the onset of glomerulonephritis. Controls were age- and sex-matched mice (n = 10) without aminoguanidine treatment. By glomerular microdissection and reverse-transcription competitive polymerase chain reaction, we found that glomerular iNOS/beta-actin and TGF-beta1/beta-actin mRNA ratios were reduced 15.1% (P<0.05) and 61.3% (P<0.01), respectively, in aminoguanidine-treated mice. Aminoguanidine significantly reduced the glomerular iNOS staining, urinary nitrite production and degree of glomerulosclerosis. In addition, the glomerular volume and mean glomerular cell number were reduced 33.2% (P<0.01) and 32.8% (P<0.01), respectively. Likewise, the urinary proteinuria was also significantly reduced by aminoguanidine. These results indicate that administration of aminoguanidine may reduce the progression of glomerulosclerosis in NZB/W F1 mice, possibly through inhibition of glomerular nitric oxide production.
Effect of Ration on Free Choice Consumption of Calcium-Phosphorus Supplements by Dairy Cattle

Abstract Daily individual consumption of dicalcium phosphate by 69 lactating Holstein cows was measured for 22 consecutive weeks in a continuous feeding trial. The four rations fed did not differ significantly in their influence on the amount of free choice mineral consumed. Individual variation in mineral consumption was large in all four ration groups. The correlation between free choice consumption of dicalcium-phosphate and the requirement for calcium and phosphorus was small though significantly different from zero, Three rations of greatly different calcium content were offered ad libitum to three groups of 15 yearling dairy heifers each in a 3 × 3 Latin square design with six-week periods. Each pen was offered a dicalcium phosphate (pH 3.5) and a defluorinated phosphate (pH 8.5). Type of ration had no significant effect on the total amount of supplement eaten. Dicalcium phosphate was preferred to defluorinated phosphate under all ration regimes. There appeared to be little relationship between consumption of the supplements and the need for calcium and phosphorus. There was no indication of an attempt by the heifers to narrow a wide calcium to phosphate ratio by selection of an appropriate mineral supplement or to widen a very narrow ratio by the same means. When dairy cows and heifers were fed rations which provided calcium and phosphorus in excess of requirements, luxury consumption occurred when simple calcium-phosphorus supplements were offered free choice.
Vacuum radiative level shift and spontaneous-emission linewidth of an atom in an optical resonator.

The center frequency and linewidth of the $^{1}S_{0}\ensuremath{-}^{1}P_{1}$ resonance line of barium atoms placed near the center of a concentric optical resonator are studied as functions of cavity tuning. Shifts in the transition center frequency, due to radiative level shifts, and changes in linewidth, due to enhanced and suppressed spontaneous emission, are observed. A QED calculation which explicitly includes the resonator mode density gives good agreement with the data.
Bovine pineal tripeptide threonylseryllysine retards puberty in female rats.

When injected into rodents, the bovine pineal tripeptide threonylseryllysine (TSL) elicits diverse antireproductive effects in a number of animal models. Extensive studies of its effects on pubertal development have not been carried out, however. In the present study, 1.0 μg of T-S-L was administered daily to female Charles River CD rats throughout the peripubertal period, and effects on vaginal opening time, ovarian histology, and serum luteinizing hormone (LH) levels were observed. Since TSL is known to alter the action of luteinizing hormone releasing hormone (LHRH), it was postulated that this antireproductive tripeptide would delay the time of vaginal opening associated with first ovulation. Two hundred eighty-seven weanling females were housed at 22°C under a 14L:10D photoperiod. They were divided into three groups for daily intraperitonal injections of either saline (SAL), 1.0 μg TSL, or 5.0 μg melatonin (aMT) beginning on the 23rd day of life. Subgroups of nine to ten rats from each treatment group were sacrificed on days 28, 30, 32, 33, 34, 35, 36, 37, 38, and 40. Although the body weights of all animals increased significantly during the course of the study, no significant differences were observed in this parameter among rats treated with saline, aMT, or TSL. Vaginal opening time was significantly delayed by TSL between days 32 and 40, and uterine weights were significantly lower in this group. Prepubertal increases in serum levels of LH were also significantly reduced. At the dose utilized, aMT was without significant effects on these parameters. Rats sacrificed between 32 and 38 days of age were classified on the basis of uterine weights and ovarian histology as either anestrous or in early proestrus, late proestrus, or estrus. Compared with the SAL- or aMT-treated groups, TSL treatment increased the percentage of animals in both anestrus and early proestrus. At the dose utilized the bovine pineal peptide TSL effectively delayed the onset of puberty, probably through its known inhibitory action on gonadotropin secretion. This observation may reflect the demonstrated ability of TSL to bind to LHRH in a sequence- and residue-specific manner, resulting in modulation of this peptide's gonadotropin releasing activity.
Comparison of Four Procedures for Equating the Tests of General Educational Development.

Procedures used to compare the results from item response: theory as well.as.mOretraditional equating methods were described'and critically.analyzed. The implications of the. comparison of equipercentile, linear.,' one-parameter (Basch) , andthree-parameter .methods for equating twelve fOrms Of.each of.the five tests. of General Educational:Development (GED)' were discussed. The use of factor analyses to assess test dimensionality, examination of equating curves, examination of item parameter. estimates for' extremes, comparison of equating sample means and variances, and Cross-validation analyses were recommended for use by,testing programs: contemplating a switch from traditional to iteuLrespOnse theory equating. -The three-paraieter equating method produced unacceptable equating results--possible becaute only 200 examinees per equating form were used.. The one7parameter' (Rasch, method produced results which were as stable as those for the traditional methods. (Author): . *********************************************************************** * Reproductions tuppliedy EDRS are the bett that can be made *. froi the original document. ********************************************************************** DEPARTMENT OF EDUCATION NA AL, INSTITUYE OF EDUCATION ED#ATI NAL RESOURtES INFORMATION CENTER (ERIC) tir This document has been reproduced as received from the person or organization originating it. CJ Minor changes have been made to improve reproduction quality. ie Points of view or opinions stated in\this docur;leht do not necessarily represent official NIE position or policy. COMPARISON OF FOUR PROCEDURES FOR EQUATING THE. TESTS OF GENERAL EDUCATIONAL DEVELOPMENTr Michael J, Kolen Hofstra University "PERMISSION TO REPRODUCE THIS MATERIAL HAS BEEN GRANTED BY Douglas R. Whitney TO THE EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC)." American Council .on Education-Paper presented at thennual Meeting of. the American EdUcational Research Association in Los Angeles,-CalifOrnia,.April 1901, ... . . _ 4, :COMPARISON OF FOUR. PROCEDURES FOR EQUATING THE TESTS OF GENERAL EDUCATIONAL DEVELOPMENT
Fuzzy compromise: an effective way to solve hierarchical design problems

The importance of being able to decompose largescale engineering problems cannot be overemphasized. Many decomposition algorithms require that all variables, constraints and objectives be specified. In practice this is often unattainable, hence we propose to formulate design problems using fuzzy set theory. Modelling design problems in a fuzzy environment has three advantages. First, some problems may be modelled more accurately using fuzzy relationships rather than using crisp (not fuzzy) ones. Second, fuzziness effectively extends the solution space. Third, the extent of fuzziness may be decreased as the design evolves, thus one model may be used throughout the design process. A fuzzy decomposition method using the fuzzy compromise Decision Support Problem (DSP) is presented in this paper. Using this approach, although the system modelled may be fuzzy, the solution is crisp. The method is demonstrated using a portal frame problem, results from the fuzzy formulation are compared with results from a crisp formulation.
Real Simulacra Redux: Barbie and Jane Versus the Wooden Nutmegs of Connecticut

En 1993, c'est un lieu commun de la theorie post-moderne que de considerer l'Amerique comme etant le fief de la culture du simulacre. Il faut approfondir, cependant, la comprehension du processus cognitif collectif a partir duquel se produit la fetichisation des simulacres reels. L'A. se propose de re-positionner les programmes de « narativisation historique » dans les domaines cognitifs et de chercher les differents processus cognitifs qui permettent de separer le reel de l'imaginaire, definis en tant que modeles precis de pensee dans la culture contemporaine
Calculation of electron affinities for small homonuclear and heteronuclear diatiomic molecules with the CBS-QB3 and G3B3 method: basis set effects, and need for further development

Abstract It has been previously published that density functional theory (DFT) methods do not perform very well when they are used for the calculation of electron affinities. In this report, it will be shown that when DFT methods (the B3LYP method is used) are coupled to high-level ab initio methods such as the CCSD (T) or QCISD (T) methods, highly accurate results are obtained. Among the most recent of these methods are the CBS-QB3 and G3B3 variants of the CBS-Q and G3 method, respectively. Basis set effects within the DFT methods for these calculations will also be addressed.
A Synaptic Ras-GTPase Activating Protein (p135 SynGAP) Inhibited by CaM Kinase II

Ca^(2+) influx through N-methyl-D-aspartate– (NMDA–) type glutamate receptors plays a critical role in synaptic plasticity in the brain. One of the proteins activated by the increase in Ca^(2+) is CaM kinase II (CaMKII). Here, we report a novel synaptic Ras-GTPase activating protein (p135 SynGAP) that is a major component of the postsynaptic density, a complex of proteins associated with synaptic NMDA receptors. p135 SynGAP is almost exclusively localized at synapses in hippocampal neurons where it binds to and closely colocalizes with the scaffold protein PSD-95 and colocalizes with NMDA receptors. The Ras-GTPase activating activity of p135 SynGAP is inhibited by phosphorylation by CaMKII located in the PSD protein complex. Inhibition of p135 SynGAP by CaMKII will stop inactivation of GTP-bound Ras and thus could result in activation of the mitogen-activated protein (MAP) kinase pathway in hippocampal neurons upon activation of NMDA receptors.
Do Femtonewton Forces Affect Genetic Function? A Review

Protein-Mediated DNA looping is intricately related to gene expression. Therefore any mechanical constraint that disrupts loop formation can play a significant role in gene regulation. Polymer physics models predict that less than a piconewton of force may be sufficient to prevent the formation of DNA loops. Thus, it appears that tension can act as a molecular switch that controls the much larger forces associated with the processive motion of RNA polymerase. Since RNAP can exert forces over 20 pN before it stalls, a ‘substrate tension switch’ could offer a force advantage of two orders of magnitude. Evidence for such a mechanism is seen in recent in vitro micromanipulation experiments. In this article we provide new perspective on existing theory and experimental data on DNA looping in vitro and in vivo. We elaborate on the connection between tension and a variety of other intracellular mechanical constraints including sequence specific curvature and supercoiling. In the process, we emphasize that the richness and versatility of DNA mechanics opens up a whole new paradigm of gene regulation to explore.
Investor–State Disputes When Can Governments Break Contracts?

Since 1990, governments around the developing world have broken contracts made with multinational corporations (MNCs), but the incidence of breach varies across countries and over time. I argue that shared firm nationality is a key determinant of contract sanctity. MNCs are likely to divert investments or exit in response to breach with a firm of the same nationality but unlikely to react in ways costly to the host government otherwise. At the level of the economy as a whole, host governments gain permissive space to trade-off among national groups of investors when a greater diversity of foreign direct investment nationalities is present. I use national-, firm-, and dyadic-level data from 1990 to 2008 to demonstrate nationality-tied firm responses to breach. Counterintuitively, deeper integration with more nationally diverse MNCs enables more breach, as governments gain space to prioritize other goals over the property and preferences of foreign capital.
Market Structure, Industrial Research, and Consumers of Innovation: Forging Backward Linkages to Research in the Turn-of-the-Century U.S. Steel Industry

Although the U.S. steel industry's concentrated market structure and well-established production technology curbed active research by most steel firms, between 1880 and 1910 vertical research arrangements between steel producers and steel consumers, notably the Pennsylvania Railroad, became a key factor in promoting both increased innovation in basic steel products and increased innovative effort by steel producers, albeit slowly and gradually. Thus, research into steel was initiated not by steel producers but by steel consumers, who established in-house industrial research laboratories and interfirm cooperative research arrangements as a means to solve their technical problems with steel products. They also began to work toward creating an institution—the American Society for Testing Materials—that would allow for effective interaction with other consuming firms and, eventually, with producing firms to exchange information and build consensus.
Optimal Rate for a Queueing System in Heavy Traffic with Superimposed On-Off Arrivals

A rate control problem is addressed for a queueing system in heavy traffic. The arrival process is a stationary heavy-tailed On-Off process and service is done at a constant rate (controlled). With an infinite horizon discounted cost function, the main result shows the existence of an optimal rate and specifies a bound on this optimal rate. As a part of the analysis, we solve an approximating control problem driven by fractional Brownian motion. We also derive an asymptotic maximal bound on the second moment of the centered On-Off process, which is a key ingredient of the proof and is of independent interest.
Building robust authentication systems with activity-based personal questions

A recent study found that the widely-used secret questions for Web authentication can easily be guessed. The study focused on making secret questions easier to remember for the user and harder to break by others. Our approach is authentication through the use of an individual's personal and dynamic Internet activities. We hypothesize that frequently-changing secret questions will be hard for attackers to guess. We propose three major categories of questions that are based off of user activities: network activities (e.g., browsing history, emails); physical events e.g., planned meetings, calendar items); conceptual opinions (e.g., opinions as derived from browsing, emails). Our preliminary results are encouraging and show that this new direction is promising. To improve the usability, in particular nonintrusiveness, of such a dynamic secret-question system, we also describe a concrete client-server architecture and security model for automating our authentication systems through utilizing existing artificial intelligent techniques.
Using Resistivity Arrays to Monitor Groundwater Impacts near Runoff Holding Ponds

Mineral and organic salts from beef manure contained in precipitation runoff from feedyard pen surfaces can alter the conductivity properties of soil and water receiving it. Typically, holding ponds are constructed to control runoff from concentrated animal feeding operations. The integrity of these holding ponds has come under increased scrutiny since leakage has the potential to affect soil and groundwater quality. Traditionally, ponds are monitored by installing monitoring wells at key locations to evaluate the impact of these ponds on the environment. These monitoring wells are expensive and subject to ambiguous interpretation. A subsurface resistivity array was installed at a beef cattle feedyard located at the U.S Meat Animal Research Center, Clay Center, Nebraska (Feedyard A) and at a cattle feeding cooperator site (Feedyard B). Array probes were permanently installed at Feedyard A (16 probes spaced 6.1-m apart at a depth of 30 cm) and at Feedyard B (32 probes spaced 3.05-m apart at a depth of 50 cm). Weekly readings from each site were evaluated to monitor the stability of the zone of hydration near the pond. The low hydraulic conductivity soils at Feedyard A provided a very quiescent environmental system to evaluate the resistivity array’s inherent measurement stability. Seasonal changes could easily be accounted for by variation in seasonal soil temperatures. The Feedyard B site was typified by coarse textured parent material that had high hydraulic conductivity properties. This site experienced dynamic changes week to week and throughout the season. The resistivity array system was able to adequately measure these dynamics. Additional analysis using difference maps improved the illustration of the resulting dynamic. The results of this study indicate that the resistivity array system has the potential to improve monitoring of runoff holding ponds and warrants additional validation.
A Model of the Interaction of Strategic Behavior, Corporate Context, and the Concept of Strategy

Based on a review of previous landmark studies and in the light of findings of recent research on internal corporate venturing, a model of the strategic process in large, complex firms is presented under which the propositions “structure follows strategy” and “strategy follows structure” can both be subsumed. Current corporate strategy induces some strategic behavior but changes in corporate strategy follow other, autonomous, strategic behavior.