cssi/SciSciGPT-SciSciNet huggingface dataset:
The role of sediments and bryophytes in phosphorus dynamics in a headwater stream ecosystem1

Streambed sediments and the bryophyte community are sites of retention and processing of dissolved phosphorus (DP) in Bear Brook, an undisturbed headwater stream in the Hubbard Brook Experimental Forest. Sorption of DP by sediments in an equilibrium phosphorus concentration for silty and sandy sediments was equal to the mean ambient DP concentration (2 micrograms P/liter). The buffering capacity of the sediments was at a maximum in the pH range characteristic of Bear Brook. Silty sediments had a higher phosphorus buffering capacity than sandy sediments, and leaf-leachate phosphorus was sorbed less than orthophosphate. Phosphorus sorption increased as sediment particle size decreased and as aluminum and organic matter content increased. The microbial community appears to be a relatively minor component of phosphorus buffering capacity in these sediments.
Differential expression of connexin 43 in the chick tangential vestibular nucleus.

The chick tangential nucleus is a major vestibular nucleus whose principal cells receive convergent inputs from primary vestibular and nonvestibular fibers and participate in the vestibular reflexes. During development, the principal cells gradually acquire the mature firing pattern in part by losing a specific potassium current around hatching (H). Here we focus on characterizing the expression of connexin 43 (Cx43), a gap junction protein found mainly between astrocytes in the mature brain. The astrocytic syncytium plays an important role in maintaining extracellular potassium ion balance in the brain. Accordingly, it is important to characterize the potential of this syncytium to communicate during the critical developmental age of hatching. Using fluorescence immunocytochemistry, we investigated whether Cx43 staining was concentrated in specific cellular compartments at H1 by applying well-known markers for astrocytes (glial fibrillary acidic protein; GFAP), oligodendrocytes (antimyelin), neurons (microtubule-associated protein 2), and synaptic terminals (synaptotagmin). GFAP-positive astrocytes and GFAP-negative nonneuronal cells around the principal cell bodies were labeled with Cx43, suggesting that Cx43 was expressed exclusively by nonneuronal cells near the neuronal elements. Next, the developmental pattern of expression of Cx43 was studied at embryonic day 16 (E16), H1, and H9. At E16, Cx43 was present weakly as random small clusters in the tangential nucleus, whereas, at H1, overall staining became localized, with increases in size, brightness, and number of immunostained clusters. Finally, at H9, Cx43 staining decreased, but cluster size and location remained unchanged. These results suggest that Cx43 is developmentally regulated with a peak at birth and is associated primarily with astrocytes and nonneuronal cells near the principal cell bodies.
EMPIRICAL ANALYSIS ON THE PREDICTORS OF FUTURE SPOT RATES

This paper examines the issue of the prediction of future spot rates by applying the seemingly unrelated regression technique to four major currencies using data from January 1974 to September 1982. The empirical evidence indicates that current spot rates provide a better prediction of future spot rates than do current forward rates. In further rolling subsample studies, the estimated coefficients for current forward rates (or spot rates) are found to be sensitive to the new information. An important implication of this paper is that since the estimated coefficients vary over time, the underlying pattern of the generated coefficients should be extrapolated and incorporated into the exchange rate predictions.
Radiation nephritis causing nephrotic syndrome

Clinical symptoms of acute radiation nephritis with nephrotic syndrome developed in a fifty-six-year-old woman after abdominal radiation therapy for an astrocytoma of the spinal cord. The diagnosis of radiation nephritis was confirmed by renal biopsy. To our knowledge, this is the first documented case of radiation nephritis associated with nephrotic syndrome.
Missile Guidance Algorithm Design Using Particle Swarm Optimization

This paper presents a PSO guidance (PSOG) algorithm design for the pursuit-evasion optimization problem. The initialized particles are randomly set within the guidance command solution space and th...
Power amplifier resilient design for process, voltage, and temperature variations

Abstract This paper presents RF power amplifier adaptive body bias compensation technique for output power and power-added efficiency resilient to process, supply voltage, and temperature (PVT) variations. The adaptive body biasing scheme uses a current source for PVT sensing to provide resilience through the threshold voltage adjustment to maintain power amplifier performance over a wide range of variability. Analytical equations are derived for physical insight. ADS simulation results show that the resilient body biasing design improves the robustness of the power amplifier in output power and power-added efficiency over process, supply voltage, and temperature variations.
Analysis of intraday herding behavior among the sector ETFs

Abstract A body of literature has emerged suggesting that investors herd, or tend to make investment decisions on the basis of information provided by the trades of other market participants. In this paper, we use intraday data to examine whether traders herd during periods of extreme market movements using sector Exchange Traded Funds (ETFs). Two procedures, one based on identifying extreme up market and down market periods and the other based on incorporating a nonlinear term in a regression specification, are used to identify the possibility of the existence of herding behavior in nine sector ETFs traded on the American Stock Exchange. The results support the conclusion that investors do not herd during periods of extreme market movements using ETFs. Furthermore, we show that the market reaction to news is not symmetric for up markets and down markets.
Pennsylvanian Rocks of Eastern Interior Basin

Pennsylvanian rocks of the Eastern Interior basin underlie about 53,000 square miles in Illinois, Indiana, and western Kentucky, with small outliers in Missouri and Iowa, attaining maximum thickness of about 2,500 feet in southeastern Illinois. At the beginning of the Pennsylvanian there was a regional southwest slope furrowed by numerous subparallel valleys as deep as 200 feet. An eastward slope prevailed along the western border of the basin with smaller valleys. Subjacent strata range in age from the Middle Ordovician St. Peter sandstone to the Upper Mississippian Kinkaid limestone. Because of topographic unevenness and early Pennsylvanian tectonism, the early Pennsylvanian Caseyville and Tradewater units vary from zero to 1,200 feet. Movements along the LaSalle anticl ne and Duquoin monocline are reflected in an isopach map of this interval. In later Pennsylvanian Carbondale and McLeansboro time the intervals increase regularly toward the southeast, showing that the present southeast border of the basin is due to post-Pennsylvanian deformation. Structural relief on the No. 2 coal ranges from +700 to -913 feet. Similar systems of nomenclature are used in Illinois and Kentucky but different names are employed in Indiana. The significant features of 46 key beds are described. Clastic ratios average about 8 parts clastic to 1 non-clastic. Sand-shale ratios are extremely variable due to lenticular sandstones at more than 20 positions. Many sandstones occupy channels excavated into underlying strata; others seem to be off-shore barrier beach deposits. There are marine limestones at about 25 different positions, generally thickening toward the western border of the basin, but each has its individual pattern of distribution. Lower Pennsylvanian sandstones are highly quartzose and derived from older sediments; later sandstones are micaceous and feldspathic with much interstitial clay, evidently a first-cycle deposit from a metamorphic terrane. Coals are generally banded, and range in rank from high-volatile to medium-volatile bituminous. Refractory underclays ar found in the Lower Pennsylvanian in northern Illinois and in the area near St. Louis, Missouri. Cyclic sedimentation is very well displayed with at least 25 alternations of coal, marine limestone, shale, sandstone, and underclay. Early Pennsylvanian sediments came from the east and northeast but the source of the later micaceous sandstones is still uncertain. Most marine invasions came from the west, north of the Ozark uplift, but some in the early Pennsylvanian probably entered the basin from the east and south. The basin has produced about 5 billion tons of coal and 325 million barrels of Pennsylvanian oil. Other industries based on Pennsylvanian materials are refractories, common brick and tile, road metal, agricultural limestone, portland cement, rock asphalt, glass sand, foundry sand, and whetstone.
A computer program for calculating non-LTE model stellar atmospheres

Abstract The program calculates model stellar atmospheres, assuming plane-parallel, horizontally homogeneous atmosphere in radiative and hydrostatic equilibrium, and allowing for departures from local thermodynamic equilibrium (LTE) for a set of occupation numbers of selected atomic and ionic energy levels. The program is very flexible as to the choice of chemical.
Binding of cupric ions to bovine serum albumin

Abstract The binding of cupric ions to bovine serum albumin was investigated by using a cupric‐ion‐specific electrode. When using a modified form of the Scatchard equation, it was determined that there are at least two classes of binding sites on bovine serum albumin for cupric ions. One class has three binding sites of relatively strong affinity, with an average binding constant of 3.0 × 106. The other class has about 16 binding sites of relatively weak affinity, with an average binding constant of 2.0 × 104.
Historical reflections and new positions on perceptual computing

This paper traces the historical origins of perceptual computing and credits Tong and Bonissone (IEEE Trans Syst Man Cybern 10:716---723, 1980) as being the first to originate it but under a different name. It also takes the position that interval type-2 fuzzy sets, and not type-1 fuzzy sets, should be used in perceptual computing. Finally, it proposes some testable guidelines for when a solution (e.g., perceptual computing) may be branded computing with words.
Diurnal transport effects on the F-region plasma at chatanika under quiet and disturbed conditions

High latitude ionospheric model predictions are compared with the diurnal variations of plasma convection velocities and electron densities observed at Chatanika, Alaska, on geomagnetically quiet and disturbed days near equinox. Since the time-dependent variation of the magnetospheric electric field was not known, plasma drift velocities and ion densities are calculated for two different convection-precipitation models, each of which corresponds to a different level of magnetic activity. Model calculations for the magnetically quiet day produced plasma drift velocities and electron densities that were in good agreement, both qualitatively and quantitatively, with the measurements. The two models have demonstrated the relative sensitivity of the high latitude ionosphere to different combinations of magnetospheric convection and induced vertical drifts associated with thermospheric winds.
Investigating the correlation between mathematical pre-knowledge and learning gains in service physics

An investigation was undertaken into the relationship between the initial mathematics knowledge of students and their success in a service physics course aimed at science students who require an understanding of basic physics concepts but who are not studying for a physics major. An appropriate method for performing this investigation was developed, implemented and analysed. Results from a small, self-selected sample indicated a correlation between the initial mathematical knowledge of students and learning gains obtained during the course.
Stress, duration, and intonation in Arabic word-level prosody

Abstract This paper presents the results of a study of the expression of word-level prosody in Jordanian Arabic. The study focuses on the durational, spectral, and fundamental frequency correlates of stress and word-final juncture in the speech of four speakers. Speakers exhibit extensive final lengthening effects and a smaller effect of stress and penultimate lengthening. Stress lengthening correlates with higher first formants, while penultimate lengthening does not. Analyses of fundamental frequency patterns support an analysis in terms of pitch accents associated with stressed syllables and juncture-marking phrasal pitch specifications. Finally, lengthening effects are sensitive to higher level prosodic juncture. These results are discussed in comparison with similar results in studies of English speakers.
Modeling personalized occupancy profiles for representing long term patterns by using ambient context

Abstract Occupancy is a crucial factor in deciding the load for a building's HVAC system. To incorporate and account for occupancy, most simulation tools use fixed design profiles that are based on statistical methods, which use large-scale occupant surveys and/or observations from a number of similar buildings. Such survey and observational data are labor- and time- intensive to gather, and do not accurately represent the actual occupancy patterns. Consequently, fixed design profiles may deviate from actual occupancies of a building. Data acquired by wireless sensor networks could provide high-resolution and accurate information for describing indoor ambient variations caused by occupancy status changes and screening irregular presence. This paper proposes a framework to model personalized occupancy profiles for representing occupants' long-term presence patterns. A personalized occupancy profile is described as typical weekday/weekend occupancy probability as a function of time for a specific occupant. Regression modeling, time-series modeling, pattern recognition modeling and stochastic process modeling are tested to model the expected occupancy status and their performances are compared in terms of the degree of statistical approximation to actual occupancy. The paper evaluates the impact of implementing personalized occupancy profiles on energy simulation results by simulating energy consumption of four thermal zones in a building for four months using OpenStudio. The results show that the personalized occupancy profiles acquired through time-series modeling, pattern recognition modeling and stochastic process modeling outperform the fixed design profiles and observation-based profiles currently used in building energy simulations.
What Designers Talk About When They Talk About Context

Context has long been considered an important component of design, but as technology becomes more capable of inferring the user's behavior and environment, what constitutes context has become an increasingly pressing concern to designers. Although design frameworks and models have been proposed for context-aware computing systems, there has not yet been research that focuses on understanding context empirically from the perspective of the designer. To address this, we present an analysis of 11 in-depth interviews we conducted with designers of a variety of context-aware systems. Our analysis of the artifacts and interviews reveal five concerns designers address in their work. Furthermore, we present a process model that illustrates how context-aware system designers address these concerns. Our findings demonstrate the central role that designers' views of context plays in (a) framing a design space, (b) encoding the relevant features of context, (c) unifying possible solutions within that design space, an...
SCHOOL EFFECTIVENESS AND THE DISADVANTAGED SCHOOLS PROGRAM

The Disadvantaged Schools Program (D.S.P.) has been an important and integral part of education for many students in Australia for over a decade. The original goals and philosophy of the program still hold true today. However, we suggest that perhaps it is time to build on the foundation which has been developed by adding a much stronger academic strand as part of the overall D.S.P. mission. Recent school effectiveness findings offer a powerful and compatible opportunity for the D.S.P. to provide a more complete education for their students. The adoption of the school effectiveness characteristics by D.S.P. schools would not interfere with, but rather would enhance an already valuable program. The eight most important school effectiveness variables are reviewed in this article. We then argue that by combining the current focus of the D.S.P. with the focus of effective schools research, the overall quality of education received by students in Program schools can be enhanced. We argue that critical elements of the effective schools movement, such as emphasis on academic success and cognitive skills, can help create D.S.P. projects that produce a wider array of important student outcomes. By making effective school variables an important aspect of the D.S.P., we believe that both equity and quality will be emphasized to a greater extent than they are currently.
Fluid production and isograd reactions at contacts of carbonate‐rich and carbonate‐poor layers during progressive metamorphism

With increasing temperature during prograde metamorphism reactions will occur first at the lithological contacts of mixed pelite and calcsilicate terranes. At these interfaces, a fluid of lower chemical potential of H2O and CO2 than that required to produce a fluid in either layer can be produced whether reaction is caused by fluid infiltration or is initially fluid absent. If the interface region does not allow fluid transport then as temperature increases, a fluid pressure greater than lithostatic can develop. At some degree of over-pressure relative to rock pressure, the fluid hydraulically fractures the rock and a gradient in fluid composition away from the contact can be produced. These phenomena occur at the compositional interfaces whenever univariant reactions in the differing layers cross on a temperature vs. mole fraction of CO2 diagram with slopes of opposite sign. The first occurrence of these reaction products at lithological contacts delineates an isograd that defines temperature as well as the mole fraction of CO2 at constant pressure in systems open to fluid transport. These isograds can be contrasted with fluid-producing isograds in closed systems. As an illustration of possible effects, the reactions quartz + clinozoisite + muscovite = anorthite + K-feldspar + H2O and phlogopite + quartz + calcite = tremolite + K-feldspar + H2O + CO2 at 4 kbar are analysed and equations for fluid production and transport are developed.
Multiple wavelet-tree-based image coding and robust transmission

In this paper, we present techniques based on multiple wavelet-tree coding for robust image transmission. The algorithm of set partitioning in hierarchical trees (SPIHT) is a state-of-the-art technique for image compression. This variable length coding (VLC) technique, however, is extremely sensitive to channel errors. To improve the error resilience capability and in the meantime to keep the high source coding efficiency through VLC, we propose to encode each wavelet tree or a group of wavelet trees using SPIHT algorithm independently. Instead of encoding the entire image as one bitstream, multiple bitstreams are generated. Therefore, error propagation is limited within individual bitstream. Two methods based on subsampling and human visual sensitivity are proposed to group the wavelet trees. The multiple bitstreams are further protected by the rate compatible puncture convolutional (RCPC) codes. Unequal error protection are provided for both different bitstreams and different bit segments inside each bitstream. We also investigate the improvement of error resilience through error resilient entropy coding (EREC) and wavelet tree coding when channels are slightly corruptive. A simple post-processing technique is also proposed to alleviate the effect of residual errors. We demonstrate through simulations that systems with these techniques can achieve much better performance than systems transmitting a single bitstream in noisy environments.
The comparative metabolism and toxic potency of aflatoxin B1 and aflatoxin M1 in primary cultures of adult-rat hepatocytes.

Abstract Both aflatoxin B 1 (AFB 1 ) and a hydroxylated metabolite, aflatoxin M 1 (AFM 1 ), were potent cytotoxins and genotoxins to primary cultures of rat hepatocytes. However, AFB 1 stimulated the release of lactate dehydrogenase into the culture medium and the loss of viable cells from the monolayer at lower doses than did AFM 1 . The lowest toxic doses of AFB 1 and AFM 1 were 0·05–0·1 and 0·6 μ g/ culture, respectively. Genotoxicity, determined by an assay for stimulation of DNA repair, was apparent at lower doses than was cytotoxicity. AFB 1 was again more potent than AFM 1 , stimulating DNA repair at 0·025 μ g/culture. compared to the lowest genotoxic dose of AFM 1 of 0·05 μ g/culture. At higher doses (1·2–2·4 μ g/culture) the responses due to both aflatoxins in the cytotoxicity and DNA-repair assays were approximately equal. The metabolism of a low dose ( c. 0·17 μ g/culture) of [ 14 C]AFB 1 and [ 3 H]AFM 1 by cultured hepatocytes differed significantly. After 1 hr, 50% of the [ 14 C]AFB 1 remained unchanged in the culture medium, whereas about 18 hr were required for the same amount of [ 3 H]AFM 1 metabolism to occur. [ 14 C]AFB 1 was metabolized to AFM 1 , to polar metabolites recovered in the aqueous phase after chloroform extraction, and to metabolites covalently bound to hepatocyte macromolecules. [ 3 H]AFM 1 was also metabolized to polar metabolites and to forms bound to macromolecules. The degree of covalent binding of the aflatoxins correlated with their cytotoxicity and genotoxicity at lower doses. After a 24-hr incubation, 12·5% of the dose of [ 14 C]AFB 1 was covalently bound to macromolecules compared to 1·5% of [ 3 H]AFM 1 . Although AFM 1 was less potent than AFB 1 in cytotoxicity, DNA-repair and covalent-binding assays using primary cultures of hepatocytes, AFM 1 was still active at relatively low doses and therefore is probably a potent hepatotoxin in vivo .
Ab initio theoretical study of dipole-bound anions of molecular complexes (HF)n−, n=5–9

Abstract Ab initio calculations have been performed to determine structures and electron detachment energies of the hydrogen fluoride hydrogen-bonded polymers, (HF) n − , n =5–9. In these systems, the excess electron is bound by virtue of the dipole–electron interaction. It was found that, unlike the neutral complexes which form cyclic structures, the equilibrium geometries of the anions have “zig-zag” linear shapes. For all the five complexes, the predicted vertical detachment energies are positive (307, 363, 405, 437, and 461 meV for (HF) 5 − , (HF) 6 − , (HF) 7 − , (HF) 8 − , and (HF) 9 − , respectively). These results were obtained at the Moller–Plesset second-order level of theory at the geometries of the anions calculated at the Hartree–Fock level. The calculations also indicate that up to n =8, the (HF) n − anions are metastable systems with respect to electron detachment and simultaneous transformation of the cluster to the most stable cyclic configurations. However, calculations predict that starting from (HF) 9 − the linear HF cluster anions are adiabatically stable systems.
Switch studies: a review

Many physicians and patients wish to switch from successful protease inhibitor (PI)-based regimens to alternative regimens, usually composed of a nonnucleoside reverse transcriptase inhibitor (NNRTI) or abacavir plus two nucleoside reverse transcriptase inhibitors (NRTIs). This reflects a desire to avoid or reverse the metabolic changes observed during long-term PI-based antiretroviral therapy; to alleviate PI-associated adverse effects; and to improve adherence by simplifying the regimen. Data from a number of randomized and cohort PI switch studies are reviewed. Overall, the results of these studies are mixed, perhaps because of limitations in study design, patient number and duration of follow-up. In most studies, the frequency of virological failure is reduced by switching to a NNRTI regimen. Switching to an abacavir-based regimen is associated with two-fold higher risk of virological failure if mutations in the reverse transcriptase gene pre-exist. Improvements in metabolic and lipid abnormalities have not been uniform but favourable lipid changes have been reported, particularly after switching to nevirapine. Resolution of lipodystrophy symptoms has not been demonstrated objectively, perhaps because of insufficient follow-up and/or the role of NRTIs in this syndrome.
On the defect structure of strontium titanate with excess SrO

The defect structure of strontium titanate with Sr to Ti ratios of 1.002, 1.005 and 1.008 was determined by measuring the equilbrium electrical conductivity at 950 and 1000° C as a function of oxygen partial pressure in the range 10o to 10−22 atm. The measured conductivity data were similar to those obtained in the sample with Sr/Ti=1.000. These observations indicate that the incorporation of excess SrO in strontium titanate with ideal composition does not generate any charged defects. A model involving the formation of a shear-structure is considered in order to accommodate the excess SrO in the system.
Impact dynamics simulation for multilayer fabrics

High-strength fabrics are employed in a wide range of ballistic protection and blast mitigation applications. They are normally used in a multilayer configuration. General numerical models of impact, perforation, and fragmentation processes in multilayer fabrics must account for complex contact–impact dynamics and include general thermomechanical coupling. A hybrid particle-element formulation has been developed to simulate impact and perforation in plain weave fabrics. Simulation results show good agreement with experiment, for fragment simulating projectile impacts on both aramid and ultra high molecular weight polyethelene soft armor materials. Copyright © 2010 John Wiley & Sons, Ltd.
Erectile dysfunction and dyslipidemia: relevance and role of phosphodiesterase type-5 inhibitors and statins.

ABSTRACT Introduction There is a close link between hyperlipidemia/dyslipidemia and erectile dysfunction (ED), with endothelial dysfunction as a common mechanism. Both ED and hyperlipidemia/dyslipidemia are rising in prevalence with mounting evidence that these conditions are harbingers of cardiovascular disease. Aim This review was conducted to provide an update on the epidemiology and oral therapy of both dyslipidemia and ED, the connection between these two conditions, and clinical outcomes relating to the use of statins and phosphodiesterase type-5 (PDE5) inhibitors in men with ED who have associated dyslipidemia. Methods A systematic search was performed of MEDLINE and EMBASE research databases to obtain articles pertaining to the epidemiology, mechanism, and clinical outcomes of statins and PDE5 inhibitors in men with ED and associated dyslipidemia. Main Outcome Measures The clinical and preclinical studies related to ED and dyslipidemia are analyzed and their findings are assessed and summarized. Results Hyperlipidemia/Dyslipidemia constitute a vascular risk factor having a considerable impact on erectile function. Furthermore, the role of endothelial dysfunction in the pathophysiology of both ED and dyslipidemia is paramount suggesting the importance of comanaging these conditions. Therefore, hyperlipidemia/dyslipidemia when present in patients with ED should prompt management with diet/exercise as well as appropriate pharmacotherapy. With ED being often associated with comorbidities, the use of concomitant pharmacotherapies enhances opportunities for managing the overall global cardiometabolic risk. Newer studies assessing the effect of PDE5 inhibitors in men with dyslipidemia will shed more light on the clinical profile of these agents when used in this patient population. Conclusions While dyslipidemia and ED are important concerns for clinicians, there exists a gap that needs to be closed between the number of individuals who have either or both conditions and those who are receiving appropriate therapy based on evidence and patient-driven goals regarding clinical outcomes. Miner M, and Billups KL. Erectile dysfunction and dyslipidemia: Relevance and role of phosphodiesterase type-5 inhibitors and statins.
Relationship between strength, function, and quality of life in older adults with chronic lung disease: is there an influence of gender?

PURPOSE: Chronic lung disease results in impaired quality of life (QOL) linked to loss of muscular strength and functional ability. Inequalities in strength and function may place women at greater risk than men. This study evaluated the influence of gender on the relationship between muscular strength, functional ability, and QOL. METHODS: Older adults (N = 40) referred to a pulmonary rehabilitation program completed assessment of upper body and lower body strength, functional ability, and QOL. To compensate for gender differences, strength was normalized for body mass. RESULTS: Strength was greater in men than in women (P < .001). No gender differences were observed for function. Men perceived better QOL related to physical function (score: 39.3 +/- 3.3 vs 27.1 +/- 2.1, P < .01) and social function (score: 58.0 +/- 5.8 vs 41.6 +/- 4.0, P < .05). In men, strength was related directly to QOL through physical function (r = 0.53, P < .05) and social function (r = 0.52, P < .05), and functional ability had no relationship to QOL. In women, strength was related to functional ability (r = 0.57, P < .05), and functional ability was directly related to QOL through physical function (r = 0.46, P < .05), and social function (r = 0.59, P < .01). CONCLUSIONS: Functional ability mediates the relationship between strength and QOL in women, while in men strength is directly related to QOL. These gender-specific pathways to QOL may be of importance to clinicians planning interventions for older adults with chronic lung disease.
THE SPECTROPHOTOMETRIC DETERMINATION OF ALLOYING AND FISSION PRODUCT ELEMENTS IN NONIRRADIATED PLUTONIUM 'FISSIUM' ALLOYS

Summary In the development of fuel processing methods for purifying Pu-Fe or Pu-Co fuel alloys, methods of chemical analysis were required for the alloying element and representative fission product elements. The initial Pu fissium alloy, which represented 10 per cent burnup after 130 days of fast fission, contained 2.5 per cent Co or Fe, 0.7 per cent Ce, 1.3 per cent La, 0.7 per cent Mo, 0.03 per cent Nb, 1.3 per cent Ru, and 0.8 per cent Zr. The concentration of many of these elements was reduced in the fuel processing to less than 0.01 per cent. It was necessary to devise chemical methods for determining each element in these concentration ranges except La, which was determined spectrographically. Dissolution of these alloys is accomplished by a sealed-tube technique, using HC1 which contains a few drops of HCl04 as a solvent, or by heating the sample with HCl and HCIO4 in a distillation apparatus until the Ru distills as the tetroxide. Cerium is separated from PuVI by precipitation of CeIV fluoride, after which it is determined spectrophotometrically as CeIV. Cobalt is determined in the presence of Pu by means of the color formed by Co in an HCl-acetone medium. Iron is determined by measuring the absorbancy of the ferrous-o-phenanthrolate complex, either in the presence of Pu or after separation by extraction of FeCl3. Molybdenum and Zr are each determined colorimetrically as the chloranilates after separation of Mo by hexone extraction from HCl solution and precipitation of Zr as the p-bromomandelate. Niobium is extracted into hexone from an H2SO4-HF medium and estimated by means of the color formed by Nb with hydroquinone in H2S04. Ruthenium is distilled as the tetroxide and estimated colorimetrically as RuIV chloride. In the higher concentration ranges, the relative standard deviation for the determination of each element is less than 2 per cent. At lower concentrations, relative standard deviations of 5 per cent are acceptable.
PRU Measures of Association for Contingency Table Analysis

This paper introduces new predictive measures of association that may be used for contingency table analysis much as the simple, partial, and multiple correlation coefficients are used for regression analysis. The new measures are based on the combination of (1) the logic of the PRE (proportional reduction in error) measures of association, (2) the use of uncertainty (or maximum-likelihood-ϰ2) as indirect measures of errors in prediction, and (3) analysis strategy of log-linear models for contingency tables.
Reactions between primary amines and magnesium or zinc dialkyls: intermediates in metal imide formation

Abstract The reactions of several different primary amines with diorganomagnesium or dialkylzinc compounds are reported. Treatment of Mg(η5-C5H5)2 with t-BuNH2 or DippNH2 (Dipp = 2,6-i-Pr2C6H3−) leads to the adduct Mg(η5-C5H5)(η2-C5H5) {NH2(t-Bu)}THF (1a) or the amide Mg(η5-C5H5)(NHDipp)THF (1b). Reaction between Mg(t-Bu)2 or commercially available Mg‘Bu’2 (‘Bu’ = statistical mixture of n-Bu and s-Bu groups) gave the dimeric amide species [t-BuMg{NH(t-Bu)}THF]2 (2a) or [‘Bu’Mg{NH(t-Bu)}THF]2 (2b). In contrast reaction of Mg‘Bu’2 with MesNH2 or TriphNH2 (Mes = 2,4,6-Me3C6H2−, Triph = 2,4,5-Ph3C6H2−) gave, after suitable workup, the bisamides Mg{(NHMes)2{OP(NMe2})3}2 (3a) or Mg(NHTriph)2(THF)2·THF (3b ·THF). A bisamide, the dimer {Mg(NCy2)2} 2 (4), was isolated in almost quantitative yield by the reaction of dibutylmagnesium with 2 equiv. of HNCy2 (Cy = cyclohexyl) whereas the trimetallic amide Mg3(μ-NHDipp)4N(SiMe3)22 (5) was isolated from the transamination reaction between DippNH2 and [MgN(SiMe3)22]2. A unique product with a rare dodecameric ring structure, (EtMgNHDipp)12 (6), was observed when MgEt2 reacts with DippNH2. Reaction between ZnEt2 or Zn(CH2SiMe3)2 and a variety of primary amines afforded a selection of structurally diverse products. The compounds isolated were: {EtZn(NHPh)THF}3 (7), {EtZn(NHMes)THF}2·0.5THF (8·0.5THF), Et2Zn4(NHDipp)4(OEt)2 (9), {EtZnNH(t-Bu)}3 (10) and (Me3SiCH2ZnNHDipp)2 (11). Crystal data: 1a, a = 10.863(2), b = 9.299(2), c = 17.787(5) A , β = 98.56(2)° , monoclinic, space group P21/c, Z = 4, R = 0.048 for 2337 (I>2σ(1)) data; 2a, a = 8.922(2), b = 16.101(4), c = 11.132(2) A , β = 111.18(2)° , monoclinic, space group P21/n, Z = 2, R = 0.081 for 2076 (I>2σ(1)) data; 3a, a = 11.174(2), b = 18.161(4), c = 18.808(6) A , β = 92.34(3)° , monoclinic, space group P21/n, Z = 8, R = 0.145 for 4945 (I>2σ(I)) data; 4, a = 22.828(5), b = 10.768(2), c = 21.350(4) A , β = 117.74(3)° , monoclinic, space group P21/c, Z = 4, R = 0.067 for 6264 (I>2σ(I)) data; 5, a = 21.754(5), b = 15.214(2), c = 20.657(4) A , orthorhombic, space group Pbcn, Z = 4, R = 0.063 for 2338 (I > 2σ(I)) data; 6, a = 26.063(5), b = 35.332(4), c = 24.535(4) A , orthorhombic, space group Pnma, Z = 4, R = 0.178 for 10408 (I > 2σ(I)) data; 7, a = 12.715; (3), b = 13.606(3), c = 22.339(5) A , α = 90.53(3) , β = 96.20(3), γ = 93.85(3)°, triclinic, space group P 1 , Z = 4, R = 0.143 for 4483 (I > 2σ(I)) data; 8·0.5THF, a = 43.58(2), b = 8.724(2), c = 38.90(1) A , β = 117.49(2)° ; monoclinic, space group C2/c, Z = 16, R = 0.058 for 5587 (I>2σ(I)) data; 9, a = 10.875(2), b = 11.669(2), c = 11.968(2) A , α = 76.17(2), β = 86.52(2), γ = 69.69(2)° , triclinic, space group P 1 , Z = 1, R = 0.043 for 2733 (I > 2σ(I)) data; 10, a = 11.281(3), b = 14.891(4), c = 15.103(5) A , β = 90.88(2)° , monoclinic, space group P21/n, Z = 4, R = 0.060 for 2363 (I>2σ(I)) data; 11, a = 10.147(2), b = 11.640(2), c = 17.521(2) A , α = 71.23(1), β = 77.50(1), γ = 69.78(1)° , triclinic, space group P 1 , Z = 2, R = 0.065 for 4752 (I > 2σ(I)) data.
Moving template analysis of crack growth—I. Procedure development

Abstract Based on a moving template procedure, this two part series will develop a method to follow the crack tip physics in a self-adaptive manner which provides a uniformly accurate prediction of crack growth. For multiple crack environments, this is achieved by attaching a moving template to each crack tip. The templates are each individually oriented to follow the associated growth orientation and rate. In this part, the essentials of the procedure are derived for application to fatigue crack environments. Overall the scheme derived possesses several hierarchical levels, i.e. the global model, the interpolatively tied moving template and a multilevel element death option to simulate the crack wake. To speed up computation, the hierarchical polytree scheme is used to reorganize the global stiffness inversion process. In addition to developing the various features of the scheme, the accuracy of predictions for various crack lengths is also benchmarked. Part II [Y. H. Guo and J. Padovan, Engng Fracture Mech. 48, 427–444 (1994)] extends the scheme to multiple crack problems. Extensive benchmarking is also presented to verify the scheme.
The mechanisms of uremic serum-induced expression of bone matrix proteins in bovine vascular smooth muscle cells

We have previously found that uremic human serum upregulates RUNX2 in vascular smooth muscle cells (VSMCs), and that RUNX2 is upregulated in areas of vascular calcification in vivo. To confirm the role of RUNX2, we transiently transfected a dominant-negative RUNX2 (DeltaRUNX2) construct in bovine vascular smooth muscle cells (BVSMCs). Blocking RUNX2 transcriptional activity significantly decreased uremic serum induced alkaline phosphatase (ALP) activity (268+/-34 vs 188+/-9.5 U/g protein, P<0.05) and osteocalcin expression (172+/-17 vs 125+/-9 ODU, P<0.05). To determine the mechanism by which uremic serum upregulates RUNX2, we examined cell signaling pathways. BVSMCs were incubated in the presence or absence of inhibitors and RUNX2 expression and ALP activity were determined. The results demonstrate that the cyclic AMP (cAMP)/protein kinase A (PKA), but not protein kinase C, signaling pathway is involved in uremic serum-induced RUNX2 expression and ALP activity in BVSMCs. To examine potential uremic 'toxins', we measured bone morphogenetic protein (BMP)-2 concentration and found that uremic serum contained increased BMP-2 (uremic serum=169+/-33 pg/ml, normal serum=117+/-15 pg/ml, P<0.05). The incubation of BVSMCs with noggin, an inhibitor of BMP, decreased RUNX2 expression. In addition, BMP-2 secretion progressively increased during calcification and uremic serum enhanced its secretion compared to normal serum. In conclusion, this study demonstrates that RUNX2 transcriptional activity is critical in uremic serum-induced bone matrix protein expression in BVSMCs and that the cAMP/PKA pathway is involved. BMP-2 is also increased in uremic serum and can upregulate RUNX2 and calcification in vitro in VSMCs.
Bemerkungen über Lumineszenz von Ionenkristallen

1 Das bei Einfangen von Elektronen in Fallen des Kristallgitters keine Lichtemission beobachtbar ist, wird erklart in Analogie zur strahlungslosen inneren Umwandlung von Anregungsenergie des Elektronensystems komplexer Molekule in atomare Schwingungsenergie. 2 Die Leuchtfahigkeit von aktiven Zentren wird gedeutet durch schwache Kopplung eines Elektronenuberganges in molekularen Komplexen mit dem Schwingungssystem des Kristallgitters. 3 Es werden Grunde fur die Annahme gegeben, das die Anregung der Phosphoreszenz in aktiven Komplexen durch den Prozes der sensibilierten Fluoreszenz erfolgt, bei der die praktisch strahlungslose Widervereinigung eines Elektrons mit einem Gitterbaustein die Sensibilisierung hervorruft. 4 Die obigen Uberlegungen werden herangezogen fur die Erklarung des Verhaltens von Tl-Alkalihalid-phosphoren.
Dietary fructose but not starch is responsible for hyperlipidemia associated with copper deficiency in rats: effect of high-fat diet.

Objective: To test the hypothesis that copper deficiency in rats may be hyperlipidemic only when the diets consumed contain nutrients which contribute to blood lipids such as fructose and high fat.Methods: Weanling male Sprague Dawley rats were fed diets which contained either starch or fructose as their sole carbohydrate source. The diets were either inadequate (0.6 μg Cu/g) or adequate (6.0 μg Cu/g) in copper and contained either high (300 g/kg) or low (60 g/kg) fat. At the end of the 4th week the rats were killed. Livers were analyzed for copper content. Plasma was analyzed for cholesterol and triglyceride concentrations.Results: High-fat diet did not increase blood lipids in rats fed a copper-deficient diet containing starch. In contrast, the combination of high-fat diet with fructose increased blood triglycerides and fructose with copper deficiency resulted in a significant increases in blood cholesterol.Conclusions: Hyperlipidemia of copper deficiency in rats is dependent on synergistic effects betw...
Abstract A27: Using community theater to educate the underserved about cancer screening and prevention

Background: In an effort to engage the lay community around issues related to colorectal and cervical cancer prevention and screening, we formed the Community Network for Cancer Prevention Forum Theater Project, a three-year funded program bringing together collaborators from several disciplines. The goal of the project is to foster communication and understanding of colorectal and cervical cancer risks and prevention strategies among target populations by discovering and addressing barriers to care. This will be accomplished by using an interactive form of community theater in a campaign that addresses health disparities and inequities. Drawing on a method that creates theater in direct collaboration with the community, we are using Forum Theater as a platform for developing colorectal and cervical cancer screening messages to be communicated at performances. Experimental Procedures: As part of the project, we have trained the first group of Community Health Workers (CHWs) to implement the theater project in Spanish-speaking Hispanic communities. The training took place once a week for seven weeks, with 16 people in attendance. A faculty member from the School of Allied Health conducted the first session, which was an evidence-based cervical and colorectal cancer content session; another faculty member from the School of Allied Health attended most of the sessions not only as an expert on behavioral psychology but as a participant in the Forum Theater training. The remaining six weeks focused in depth on Forum Theater methods and techniques, such as trust exercises, improvisation, building dramatic scenes, rehearsal techniques, maintaining effective dramatic flow, and encouraging audience participation. Throughout the training, participants developed their skills for addressing barriers and myths related to cancer screening and prevention, as well as how to address these issues with community members. Once CHWs are trained, their tasks are to identify and coordinate locations for performances, encourage participation from the communities that they serve, and to facilitate the production of linguistically and culturally appropriate performances. Expected Results and Conclusions: All of the participants completed a pre-post knowledge and attitudes survey of the content session and a self-administered questionnaire at the end of the seven weeks of training. Results of the pre-post tests indicate that the content session was effective in increasing knowledge levels and improving attitudes about the efficacy of screening and prevention for underserved populations. Findings from the questionnaire, which asked about leadership confidence, skill development, self-efficacy, and satisfaction with the program, suggest that the training program provided CHWs with the necessary tools to implement a successful community theater program for cancer prevention and screening. Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):A27.
Melatonin: failure of pharmacological doses to induce testicular atrophy in the male golden hamster.

Abstract Effects of graded doses of melatonin on reproductive function of the male golden hamster were studied. Daily injections of melatonin at 17:00 h brought about complete testicular regression when the hamster received 10, 25, and 100 ug melatonin; larger doses of 1,000 ug or 2,500 ug had a partial or no effect on testicular or accessory sex organ weights. The dose response relationship of testicular and accessory sex organ weights to melatonin treatment somewhat resembled an inverted bell-shaped curve. Plasma, LH and prolactin concentrations followed the pattern of the testicular and accessory sex organ weights; small doses of melatonin suppressed plasma, LH and prolactin while larger doses had no suppressive effects. These results indicate that melatonin can exert a reproductive inhibitory effect if injected with small, but not with larger doses.
Geomagnetically trapped protons with energies greater than 350 Mev

The intensity and pitch-angle distribution of geomagnetically trapped protons with energies greater than 350 Mev have been determined by means of data received from a Cerenkov detector on board Explorer 11. Analysis of the data reveals that the contours of constant counting rate rise more rapidly in altitude with increasing latitude than do the contours at a threshold energy of 43 Mev. The scale height of the high-energy protons along a magnetic field line is found to be significantly greater than the scale height of the lower-energy protons. The first of these results is consistent with a breakdown of the transverse adiabatic invariant J, which tends to steepen the proton energy spectrum with increasing geomagnetic latitude and altitude, assuming cosmic ray albedo neutrons to be the source of these protons. The assumptions concerning the breakdown of the invariance of J are justified through detailed numerical calculations of proton trajectories in both a dipole magnetic field and the Finch and Leaton approximation to the geomagnetic field. The second result is not consistent with the cutoff energy dependence obtained by trajectory calculations and the approximate constancy of the neutron albedo injection coefficient along a magnetic field line. The average atmospheric density ρ¯ and energy losses ( (dE/dt)¯) along a magnetic field line as a function of energy have been investigated. It is found that the variations of the scale heights of ρ¯ and ( (dE/dt)¯) are much less than the observed variation of the scale height of the radiation as a function of energy.
Computers and pedagogy: Replacing telling with interactive computer-programmed instruction

Programmed instruction has been overlooked as a way of implementing more intensive application of learning principles, possibly because it has not been well understood. Today, most of the hardware problems of past teaching machines have been solved. Instructors can now expand their effectiveness and productivity by shifting to the creation of both classroom tests and computer-interactive tutorials, a change that would leave more time for personal interaction with students. But a better understanding of the contingency of reinforcement and the science in which this concept has evolved is necessary. The computer as a teaching machine has yet to be fully exploited.