cssi/SciSciGPT-SciSciNet huggingface dataset:
Site-specific cluster labels

Abstract This article discusses the development and use of various heavy-atom clusters (Hg 4 , Ir 4 , W 11 , Au 11 , 1.4 nm Au) that can be covalently attached to specific groups (e.g., -SH, -NH 2 , -COOH) on biomolecules to produce high-resolution labels visible in the electron microscope. A number of applications are given, including labeling of proteins, carbohydrates, lipids in membranes and nucleic acids. Imrpoved immunolabeling with clusters over colloidal gold probes is discussed as well as the expanded utility of some of these clusters in TEM thin sections. With silver enhancement, the 1.4 nm gold cluster provides one of the most sensitive probes known for use in EM, light and confocal microscopy and in immunblotting.
Snow and firn properties and air-snow transport processes at Summit, Greenland

Abstract Snow–air exchange processes affect the chemistry of the atmosphere as well as the chemistry of underlying snow and firn. An understanding of the transport processes is important for quantifying and predicting changes in atmospheric chemistry and also for improving ice core interpretation. This paper focuses on the nature of diffusive and advective (ventilation) interstitial transport processes at Summit, Greenland. Field measurements of snow and firn density, permeability and microstructure are presented and compared with measurements from previous years. Density and permeability profiles follow similar general patterns from year to year; however, the specifics of the profiles show interannual variation. Field measurements of the diffusion of an inert tracer gas, SF6, through the surface wind pack yields an SF6 diffusion coefficient for the June 2000 surface wind pack at Summit of ∼0.06 cm2/s; the tortuosity of the surface wind pack was 0.5. The first direct measurements of interstitial air flow in snow due to natural ventilation in undisturbed snow are presented, for light (3 m/s) winds and moderately strong (9 m/s) winds in a hoar layer 15 cm beneath the surface. The measurements during light winds showed results characteristic of diffusion profiles, while the measurements under strong winds showed evidence of ventilation. The interstitial air flow velocities are consistent with previous modeling results.
Elucidation of the miniemulsion stabilization mechanism and polymerization kinetics

Styrene/hexadecane miniemulsions were polymerized at 50°C using a redox initiator. The miniemulsions and their corresponding latexes were characterized in terms of size, polymerization rate, and surface properties. The resulting data were analyzed to elucidate the miniemulsion stabilization and polymerization mechanisms. It was found that the free surfactant concentration exceeded the critical micelle concentration when large amounts of surfactant (60 mM sodium lauryl sulfate) were used, resulting in simultaneous micellar and droplet nucleation. Most surfactant was on the surface of the droplets (85%) or particles (95%). The fractional surface coverage was proportional to the surfactant concentration to the 0.55 power. Using a particle diameter equation, the number of particles was calculated to be proportional to the surfactant concentration to the 1.35 power. Through direct particle size measurements, a power of 1.38 was confirmed. The rate of polymerization was determined by reaction calorimetry to be proportional to the number of particles to the 0.59 power, in contrast to classical Smith–Ewart kinetics for conventional emulsions (1.0 power). The average number of radicals per particle was estimated from the rate and number data, and varied with the particle diameter to the 0.97 power. The observed kinetic dependencies were validated through an extension of Smith–Ewart theory. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3987–3993, 2003
Experimental studies on the long-term effects of methylphenidate hydrochloride

Toxicology and carcinogenesis studies of methylphenidate hydrochloride, a drug used in the treatment of attention-deficient disorders, were performed in F344 rats and B6C3F1 mice. In these studies, methylphenidate hydrochloride was administered for 2 years at doses of 0, 100, 500 or 1000 ppm in the feed to rats and at doses of 0, 50, 250, 500 ppm to mice in groups that consisted of 50 animals/dose/sex/species. The average amount of methylphenidate consumed per day was estimated to be 4-47 mg/kg/day for rats and 5-67 mg/kg/day for mice. Survival was similar in dosed and control groups. An increase in benign tumors of the liver and increased liver weights were observed in male and female mice at the high dose. An increase in hepatoblastomas was also seen in high dose male mice. Methylphenidate was not mutagenic in the Salmonella assay system, and it is hypothesized that this tumorigenic effect might be due to nongenotoxic effects of the chemical such as an increase in cell proliferation. Increased incidences of neoplasms were not seen in rats. However, there was a notable decrease in mammary gland fibroadenomas in female rats and a marginal decrease in benign pheochromocytomas in male rats. Epidemiology studies of methylphenidate have found no evidence of a carcinogenic effect in humans and like our findings in rats, report a less than expected rate of cancers in patients taking methylphenidate.
Modeling a complete Stirling engine

Abstract The assumptions of second order Stirling engine models were reviewed. An ideal adiabatic plus simple heat exchanger model was developed. The model included the external components such as the fan, combustor, and preheater. The external heat transfer to the engine heater was modeled using a log-mean-temperature difference for a constant tube surface temperature. The performance of the model of the external components compared reasonably well to experimental data. The performance of the complete engine model was also compared to experimental data of the GPU-3. By adjusting the flow dissipation to better account for unsteady flow conditions and compressibility effects, the complete engine model was able to predict engine power and brake specific fuel consumption to within ±14% over a wide range of engine speeds and mean pressures. This analysis and others suggest that second order models of Stirling engines need to account for the gradient of the divergence of velocity term in the compressible momentum equation if the mean engine pressure is low enough (less than 3.0 MPa) and the engine speed is high enough (above 30 Hz).
Shortest non-crossing walks in the plane

Let G be an n-vertex plane graph with non-negative edge weights, and let k terminal pairs be specified on h face boundaries. We present an algorithm to find k non-crossing walks in G of minimum total length that connect all terminal pairs, if any such walks exist, in 2O(h2)n log k time. The computed walks may overlap but may not cross each other or themselves. Our algorithm generalizes a result of Takahashi, Suzuki, and Nishizeki [Algorithmica 1996] for the special case h ≤ 2. We also describe an algorithm for the corresponding geometric problem, where the terminal points lie on the boundary of h polygonal obstacles of total complexity n, again in 2O(h2)n time, generalizing an algorithm of Papadopoulou [Int. J. Comput. Geom. Appl. 1999] for the special case h ≤ 2. In both settings, shortest non-crossing walks can have complexity exponential in h. We also describe algorithms to determine in O(n) time whether the terminal pairs can be connected by any non-crossing walks.
A system of singular quasilinear parabolic equations

u,(x, 0) = u,,(x), u,k 0) = u,,(x), O O ifx=O if x 0. Thus, the new feature here is the introduction of nonlinearities to cx and /I. In fact, we only assume that cy and /3 are maximal monotone graphs in R x R. These modifications greatly complicate the problem, and the techniques of [I] no longer apply. We shall treat the problem from the point of view of the nonlinear semigroup theory. The idea is rather simple. We regard the vector u = [ur , u2] in the system (1. la) as a map from [0, 00) into the Banach space X = L’(0, a) x L’(0, CT). Define an operator A in X by: [u, v] E A if u = [ur, u2] E K, c X, v = [u,, u2] E X, and there exist a vector w = [w,, w2] in W’*‘(O, a) x W2*‘(0, a) and a
Analytical formulae for estimating damage rate in the final mirrors of laser inertial fusion energy reactors based on the uncollided neutron flux

Abstract Analytical expressions were derived to calculate the average damage rate in grazing incidence mirrors (last mirrors) in an inertial fusion energy (IFE) reactor subjected to the uncollided neutrons streaming from the cavity center through the beam ducts. These expressions account for the dependence of the damage in the mirror on parameters such as the distance between the cavity center and the mirror, D , the angle of incidence, θ, the length of the mirror, X , and the mirror thickness T . The expressions lend themselves to a simple but effective means to study the impact of variations in mirror parameters and location on the damage in the mirror (quantified in terms of dpa/FPY) without the need to carry out expensive 2D or 3D calculations. Applying these expressions gives results that are in a good agreement with those based on Monte Carlo calculations. The derived formulae were used in a parametric study on the impact of variations in D , X , θ and T on the damage rate in aluminium, silicon and copper, the candidate materials in the Prometheus-L IFE reactor.
Hypolipidemic activity of 6-alkoxycarbonyl-3-aryl-1,3,5-triazabicyclo[3.1.0]hexane-2,4-diones and 2-alkoxycarbonyl-5-aryl-1,3,5-triazine-4,6(1H,5H)-diones in rodents

Significant hypolipidemic activity was demonstrated by 6-ethoxycarbonyl-3-phenyl-1,3,5-triazabicyclo[3.1.0]hexane-2,4-dione, 2-ethoxycarbonyl-5-phenyl-1,3,5-triazine-4,6(1H,5H)-dione and 2-ethoxycarbonyl-5-(4-chlorophenyl)-1,3,5-trizine-4,6(1H,5H)-dione in rodents at 20 mg/kg/day. These agents lowered serum cholesterol and triglyceride levels by approximately 40% in mice after 16 d. Tissue lipids in rat liver, small intestinal mucosa, aortic wall and feces were reduced by treatment with the agents. Very low density lipoprotein (VLDL) and low density lipoprotein (LDL) cholesterol levels were reduced in the rat; high density lipoprotein (HDL) cholesterol levels were elevated after 14 d of treatment. The activities of regulatory enzymes,e.g., acetyl-CoA synthetase, acyl-CoA:cholesterol acyltransferase, cholesterol 7α-hydroxylase,sn-glycerol-3-phosphate acyltransferase, phosphatidylate phosphohydrolase and heparin-induced lipoprotein lipase, involved inde novo synthesis of hepatic lipids were affected by the agents. The new compounds may represent another class of potentially useful hypolipidemic agents for the treatment of atherosclerosis since HDL cholesterol levels were increased and VLDL and LDL cholesterol levels were lowered by some of the agents.
Spin dynamics of an ultra-small nanoscale molecular magnet

We present mathematical transformations which allow us to calculate the spin dynamics of an ultra-small nanoscale molecular magnet consisting of a dimer system of classical (high) Heisenberg spins. We derive exact analytic expressions (in integral form) for the time-dependent spin autocorrelation function and several other quantities. The properties of the time-dependent spin autocorrelation function in terms of various coupling parameters and temperature are discussed in detail.
Mitral valve repair is durable in patients with rheumatoid arthritis

Background Rheumatoid arthritis (RA) and its treatments are associated with tissue abnormalities, which may influence surgical outcomes of repair for severe mitral valve regurgitation (MR). We examined late survival and durability of mitral valve repair in patients with RA. Methods Thirty-six patients with RA (21 male) underwent mitral valve repair for MR from August 1978 to August 2005. Median age was 70 years (range, 22 to 84). Preoperatively, 27 patients (75%) had New York Heart Association Functional Class III/IV symptoms, and 29 (78%) required immunomodulating medications for RA management. Mechanisms of MR were leaflet prolapse in 26 patients (72%), leaflet malcoaptation in 5 (14%), tethering in 4 (11%), and unknown in 1 (3%). Results All patients underwent mitral valve repair, which included posterior leaflet triangular resection in 11 patients, leaflet plication in 10, and artificial chordae placement in 3. When compared with matched control patients without RA who underwent mitral valve repair, RA patients had decreased survival (27% versus 64%, p = 0.005) and freedom from reoperation (93% versus 98%, p = 0.04) at 8 years. However, RA patients undergoing mitral valve repair had similar survival at 5 years compared with age- and sex-matched comparator patients with RA who did not undergo mitral valve surgery (65% versus 67%, p = nonsignificant). Conclusions Mitral leaflet pathology in RA patients with severe MR is similar to that of non-RA patients with mitral valve disease. Long-term survival after mitral valve repair in RA patients is equivalent to that of the general RA population without mitral valve disease, and the durability of mitral valve repair in these patients is very good.
Qualitative programming for selection decisions

Abstract Many selection decision problems involve qualitative information, the exclusion of which from optimization processes may lead to suboptimal (and possibly, disastrous) solutions. This paper presents an approach to selection decisions where some or all of the available information may be qualitative as well as incomplete. Appropriate mappings which accomplish this task are discussed in detail, and an example of the real-world application of this approach to software selection decisions is presented.
Oscillator strengths for neutral atomic carbon

Open-shell semiempirical model potential methods are used to calculate oscillator strengths for neutral atomic carbon. Results are presented for principal quantum numbers up to 12 and orbital angular momentum quantum numbers up to 4.
Effect of Acclimation on the Preferred Body Temperature of the Lizard, Sceloporus occidentalis.

The preferred body temperature was determined for several groups of Sceloporus occidentalis previously acclimated to several constant temperature levels. Acclimation to a high temperature (35°C) resulted in the selection of a lowered mean preferred body temperature, whereas acclimation to lower temperatures (12°C and 25°C) produced no change in the preferred body temperature.
The Stratification of Emotions: Some Preliminary Generalizations*

Like all valued resources, positive and negative emotions are unequally distributed in a society and constitute an important basis of social stratification. In this article, a general conceptual scheme and a more specific theory of emotions are employed to offer a preliminary explanation of the dynamics of emotional stratification. This theory attempts to explain which specific positive and negative emotions will be aroused and distributed across the social class system as well as among members of differentially evaluated social categories. The theory emphasizes the importance of repression and subsequent attribution processes as central to understanding the nature, intensity, and distribution of negative emotions among individuals in lower social classes and devalued social categories. By viewing emotions as not just reactions to the unequal distribution of other resources but, rather, as a valued or punishing resource in their own right, it becomes possible to better understand how micro-level dynamics occurring in face-to-face encounters are affected by, and have effects on, meso-level and macro-level social structures and their respective cultures. In particular, the distribution of emotions can help account for both the processes of legitimatization of macrostructures and, at the same time, de-legitimization of, and collective action against, macrostructures. This analysis of emotions questions much recent theorizing and commentary, often within postmodern analysis, about the authenticity of people’s emotions in contemporary society. The stratification of emotions is as real as inequality in money and power, and it has significant effects on the dynamics of human societies.
Identification of Fuse and Recloser Operations in a Radial Distribution System

Recloser and fuses are the main overcurrent protective devices on distribution systems. Poor coordination adversely impacts the overall power quality especially from the momentary voltage interruption and voltage sag perspectives. Therefore, the purpose of this paper is to develop a novel approach to detect and identify which protective devices operate to clear a short-circuit condition using power-quality waveform measurement data. The proposed approach is intended to evaluate performance coordination of overcurrent protective devices and help locate faults on the feeder. The effectiveness of the techniques is demonstrated using simulation and real-world data. Results indicate a promising potential for real-world deployment and applications.
Measurement of the Kβ2/Kβ 1 ratio in heliumlike krypton

We report the measurement of the Kβ2/Kβ 1 ratio of He-like krypton using the SuperEBIT electron beam ion trap at the Lawrence Livermore National Laboratory. The energy of these lines are about 15 keV, which is twice as high as the energy of such lines measured before. A comparison with theoretical predictions shows poor agreement, confirming the trend uncovered earlier where the measured result is considerably larger than predicted.
Forty days and forty nights: A biocultural perspective on postpartum practices in the Amazon

The immediate postpartum period is recognized as a special time in many societies and is commonly associated with food and work restrictions. The logic of food restrictions during a period of increased energy and protein needs has been challenged, but few data are available to test the impact of these practices on the diets of lactating women. In the eastern Amazon the immediate postpartum period is referred to as resguardo, lasts for 40-41 days and includes food taboos and work restrictions. Taking a biocultural perspective, this paper combines data on the beliefs and attitudes surrounding the practice of resguardo with quantitative data on the actual dietary intakes and activity patterns of a cohort of 23 lactating women followed from birth through 15 months postpartum. This paper addresses three topics: (1) shared ideals regarding resguardo; (2) adherence to food and work restrictions; and (3) the impact of these practices on women's dietary intakes and energy expenditure. The results show that the majority of women adhered to food taboos and work restrictions. During resguardo energy expenditure in physical activity was lower, reducing women's energy needs and allowing them to devote more time to infant care. However, energy intakes were also lower. The reduction in dietary intake was impacted more by work restrictions and the loss of women in subsistence tasks during resguardo than by adherence to food taboos. In addition to altering maternal energetic strategies, resguardo served an important social function by reinforcing bonds and, for young women, marking the transition to womanhood.
C60 secondary ion mass spectrometry with a hybrid-quadrupole orthogonal time-of-flight mass spectrometer.

A hybrid quadrupole orthogonal time-of-flight mass spectrometer optimized for matrix-assisted laser desorption ionization (MALDI) and electrospray ionization has been equipped with a C60 cluster ion source. This configuration is shown to exhibit a number of characteristics that improve the performance of traditional time-of-flight secondary ion mass spectrometry (TOF-SIMS) experiments for the analysis of complex organic materials and, potentially, for chemical imaging. Specifically, the primary ion beam is operated as a continuous rather than a pulsed beam, resulting in up to 4 orders of magnitude greater ion fluence on the target. The secondary ions are extracted at very low voltage into 8 mTorr of N2 gas introduced for collisional focusing and cooling purposes. This extraction configuration is shown to yield secondary ions that rapidly lose memory of the mechanism of their birth, yielding tandem mass spectra that are identical for SIMS and MALDI. With implementation of ion trapping, the extraction effic...
Some Notes on Multiple-Boson Processes

Methods of calculation with nonlinear functions of quantized boson fields are developed during the discussion of two problems involving multiple boson processes. In the first of these a simple treatment is given of the multiple radiation of photons by classical current distributions, a special case of which, in effect, is the infrared catastrophe. In the second illustration, generalizations of the scalar and pseudoscalar meson theories are considered in which the interaction hamiltonian depends exponentially on the meson field. In the pseudoscalar case such hamiltonians are closely related to the familiar form of pseudovector coupling. Assuming the over-all coupling of the nucleon and meson fields to be weak, calculations are made of the nuclear forces, and of the multiple production of mesons in meson-nucleon and in nucleon-nucleon collisions. In the latter events statistical independence of meson emissions is found to prevail.
The American mission to Tashkent. An examination of the mission of Roger Culver Tredwell, American Consul at Tashkent May 1918–April 1919

(1992). The American mission to Tashkent. An examination of the mission of Roger Culver Tredwell, American Consul at Tashkent May 1918–April 1919. Central Asian Survey: Vol. 11, No. 1, pp. 51-110.
Checkpointing and rollback-recovery algorithms in distributed systems

Abstract To keep it free of arbitrary failures, a distributed system may require taking checkpoints from time to time. In case of failures, the system will roll back to checkpoints where global consistency is preserved. Based on the concept of global consistency defined in this article, which eliminates both received-not-sent and sent-not-received types of inconsistencies, we developed a synchronous checkpointing algorithm C ∗ and an asynchronous roll back-recovering algorithm R ∗ with O ( VE ) message complexity, which has a relatively small coefficient, where V is the number of processors and E is the number of communication links in the system. Neither incoming message logging nor message-number calculation is needed. Our algorithms work well in complicated situations such as communication loops involving a minimal number of processors. Because of the feature of instant crash recovery and the overall low time, space, and message complexities, these algorithms are most feasible in real-time applications where rapid rollback recovery is crucial.
Resumption of Pulsatile Luteinizing Hormone Release after α-Adrenergic Stimulation in Aging Constant Estrous Rats*

The present studies attempt to define the nature of the impairment of the LH secretory response to ovariectomy in the old constant estrous (CE) rat. LH secretory patterns were characterized 2 weeks after ovariectomy in cannulated, previously normally cycling young (4–5 months old) and previously CE middle-aged (11–12 months old) and aged (21–23 months old) Long-Evans rats from which blood was sampled at 10-min intervals for 3 h. Young rats had the expected pulsatile LH secretion pattern, which was characterized by a mean LH level of 137 ± 8 ng/ml plasma, an LH pulse amplitude of 154 ± 12 ng/ ml plasma, and an LH pulse frequency of 1.16 ± 0.13 pulses/h. In marked contrast, only four of seven middle-aged and two of six old rats exhibited significant pulsatile LH secretion. Of these six animals with pulsatile LH profiles, only two had more than one LH pulse during the 3-h experimental period. The significant, large decreases in mean LH levels for middle-aged (45 ± 4 ng/ml plasma) and old (40 ± 4 ng/ml plasma...
Order-independent method of characteristics

A method of characteristics is developed for any system of partial differential equations of any finite order that admits an isovector fieldV and an initial data map satisfying a specific transversality condition. It is shown to agree with the classical method of characteristics for a nonlinear, first-order PDE and for quasilinear systems of first-order PDE with the same principal part. The method is also applicable to systems of nonlinear, first-order PDE and to systems of higher order, where it agrees with results obtained by similarity and group invariant methods. Implementation of the characteristic method is easier than classical group invariant methods because a complete, independent system of invariants of the flow generated by the isovector (group symmetry) does not have to be computed. General solutions are obtained only whenV is a Cauchy characteristic vector of the fundamental ideal; otherwise, any characteristic solution is shown to satisfy an explicit system of differential constraints. Explicit examples and comparisons with more classical methods are given.
Mathematical Analysis of Geophysical Balance Models

Abstract An analysis of an approximation to the rotating shallow-water equations is presented. The approximation removes the fast waves without introducing secular terms and is valid for physical boundaries and prepared initial data. In particular, the shallow-water equations are decomposed into two equations describing the slow and fast dynamics. The basic idea is one of enslaving in which the fast part of the solution is expressed as a function of the slow part yielding an approximation to the slow dynamics. Existence and convergence theorems are given.
Quercetin up-regulates paraoxonase 1 gene expression with concomitant protection against LDL oxidation.

Abstract Paraoxonase 1 (PON1) protects the oxidative modification of low-density lipoprotein (LDL) and is a major anti-atherosclerotic protein component of high-density lipoprotein (HDL). Quercetin, a ubiquitous plant flavonoid, has been shown to have a number of bioactivities and may offer a variety of potential therapeutic uses. We explored the roles of quercetin in the regulation of PON1 expression, serum and liver activity and protective capacity of HDL against LDL oxidation in rats. Compared to the pair-fed control group, feeding quercetin (10 mg/L) in the liquid diet for 4 weeks increased (a) hepatic expression of PON1 by 35% (p 3-fold (p
Spin-split states in metals

On decrit un nouveau type d'instabilite des surfaces de Fermi de metaux. Quand la temperature est abaissee en dessous d'un point critique, ces surfaces se deplacent les unes par rapport aux autres. On montre qu'un tel etat peut etre conduit par un certain element matriciel hors diagonale de l'interaction coulombienne. Un modele a 1 dimension est resolu dans l'approximation de champ moyen. Les anomalies associees a la transition dans la susceptibilite et dans la chaleur specifique sont etudiees
Contemporary Outcomes in Infants With Congenital Heart Disease and Bochdalek Diaphragmatic Hernia

Background Fifteen percent of infants with congenital diaphragmatic hernia (CDH) are born with a coexisting cardiac anomaly. The purpose of this study was to evaluate contemporary outcomes in this patient population and to identify potential risk factors for in-hospital mortality. Methods Data from all CDH neonates with congenital heart disease managed at a single pediatric tertiary care referral center between 1997 and 2011 were retrospectively analyzed. Results Forty (18%) of 216 CDH patients had a cardiac anomaly. This group was associated with a significant decrease in overall survival when compared with patients without cardiac anomaly (55% versus 81%; p = 0.001). There was no association between type of cardiac anomaly and mortality based on risk stratification according to the Risk Adjustment for Congenital Heart Surgery and The Society of Thoracic Surgeons–European Association for Cardiothoracic Surgery scoring systems ( p = 0.86 and p = 0.87, respectively). Birth weight was similarly no different between survivors and nonsurvivors (2.8 ± 0.6 kg versus 2.8 ± 0.9 kg, respectively; p = 0.98). There was a trend toward increased extracorporeal membrane oxygenation use among nonsurvivors ( p = 0.13). Infants with hemodynamic stability enabling subsequent cardiac repair were associated with lower mortality ( p = 0.04). Survivors had a wide spectrum of long-term morbidity, but most had some evidence of neurodevelopmental impairment. Conclusions This large single-institution series suggests that the overall prognosis of infants with concomitant CDH and congenital heart disease can be quite variable, regardless of the type of heart anomaly. Hemodynamic instability and need for extracorporeal membrane oxygenation correlate with higher mortality. Although some long-term survivors have excellent outcomes, most suffer from chronic, long-term morbidities.
The balance equation: Part 1. Response-specific inhibition and the operant-contingency puzzles

This article and Part 2 (Anger, in press) present a new molecular analysis of operant reinforcement and extinction. In this multifactor analysis, response competition can influence extinction, but the present focus is on the influences of other basic extinction processes that can be isolated and studied with procedures that minimize the effects of competing behavior. Part 1 shows that one extinction process, response-specific inhibition (RSI; Anger, 1983), can account for animal sensitivity to complex response contingencies. RSI depends on the same events that determine whether a reinforcer is contingent on a response. RSI can average those event frequencies, combine them into a single variable that varies with the contingency, and adjust responding appropriately. Part 2 uses the findings of Part 1 to derive a rational equation that describes operant responding. This linear additive equation specifies a balance between RSI-augmenting events (e.g., unreinforced responses) and RSI-decrementing events (e.g., reinforced responses). The equation predicts a different relation between responding and reinforcer frequency than do other theories, because it predicts that responding is augmented by an unrecognized variable, unreinforced non-response time during controlling stimuli.
Fluorescence in situ hybridization for the detection of aneuploidy from archived fetal cells

Background In perinatal settings, fluorescence in situ hybridization has the potential to provide specific chromosome evaluation when full karyotype analysis is not possible because there are no dividing cells. Case Based on clinical features, cases of fetal and neonatal demise were selected for evaluation with chromosome-specific probes. Sources of nondividing cells included deparaffinated tissue sections, disaggregated tissue biopsies, and archived, Giemsa-stained slides. Conclusion Diagnostic information was obtained by fluorescence in situ hybridization in three settings: 1) postmortem trisomy 21 identification from paraffin sections following unsuccessful tissue culture, 2) postmortem trisomy 18 confirmation in disaggregated cells from macerated fetal tissues, and 3) retrospective documentation of a cryptic deletion (22q-) in archived metaphase spreads. We encourage familiarity by obstetricians with fluorescence in situ hybridization for chromosomal assessment using archived fetal material.
Factoring univariate polynomials over the rationals (abstract only)

This poster presents an algorithm for factoring polynomials over the rationals which follows the approach of the van Hoeij algorithm. The key theoretical novelty in our approach is that it is set up in a way that will make it possible to prove a new complexity result. Another difference of this algorithm from prior algorithms is the practical improvement which we call early termination. Our algorithm should outperform prior algorithms in many common classes of polynomials (including irreducibles).
Fiber-matrix interface studies on bioabsorbable composite materials for internal fixation of bone fractures. II. A new method using laser scanning confocal microscopy.

In this study, a new visual characterization method was developed using laser scanning confocal microscopy (LSCM) to study morphologic properties, particularly at the fiber-matrix interface, by optical sectioning of bioabsorbable single-fiber composites. The interface gap width (IGW) between the fiber and matrix, and the changes in IGW after in vitro hydrolysis, named the gap rate (Rg), were measured from images obtained using the LSCM. Higher values for IGW and Rg showed faster degradation of the fiber-matrix interface. These parameters were used to investigate the effects of strain, wicking, different reinforcing fibers, and γ-irradiation on the fiber-matrix interface morphology. The component materials used were nonbioabsorbable AS4 carbon (C) fibers, bioabsorbable calcium phosphate (CaP), poly(glycolic acid) (PGA), and chitin fibers, and bioabsorbable poly(L-lactic acid) (PLLA) matrix. The application of strain on CaP/PLLA composites increased the IGW up to about 15%, after which there was no change up to 25%. The Rg for CaP/PLLA composites with the fiber ends exposed in vitro (permitting wicking) was greater than for CaP/PLLA with the fiber ends embedded completely within the matrix (preventing wicking). Open-end C/PLLA composites had the slowest rate of interface degradation in vitro, followed by chitin/PLLA, PGA/PLLA, and CaP/PLLA. The exposure of closed-end CaP/PLLA composites to 4 Mrad of γ-irradiation, in air at room temperature or in vacuum at 77K, accelerated the rate of interface degradation in vitro. In conclusion, an effective new visual characterization method was developed using LSCM, and it was used to show that (a) moderate strain could accelerate the degradation of the interface, (b) fiber-matrix interface wicking could accelerate the rate of degradation of the interface, (c) the rate of interface degradation depends on the type of fiber used, and (d) γ-irradiation could accelerate the rate of interface degradation. Furthermore, the results of LSCM analysis of different reinforcing fibers with a PLLA matrix agree with measurements of interfacial shear strength (IFSS) and single-fiber tensile strength reported in Part I of this study. © 1997 John Wiley & Sons, Inc. J Biomed Mater Res, 37, 353–362, 1997.
Project Management Procedures Needed to Design the Newest Four Phosphoric Acid Evaporators in North America

Abstract This paper presents the project management techniques needed to design the newest four evaporators installed in North America, and any similar project. The four evaporators included integral fluosilicic acid recovery systems, and were successfully designed, fabricated, erected and operational by mid 2009. Topics discussed in the paper include: Project Objectives, Project Stages, Scope Definition, Design Basis, Codes and Standards, Technology Selection, Capital Cost Estimation, Schedule Development and Control, Operating Cost Estimation, Value Improvement Practices, Equipment Specification, Contractor Bid Specification, Constructability Review, Construction Management, and Commissioning.
The Development of Structural and Mechanical Anisotropy in Fibroblast Populated Collagen Gels

An in vitro model system was developed to study structure-function relationships and the development of structural and mechanical anisotropy in collagenous tissues. Fibroblast-populated collagen gels were constrained either biaxially or uniaxially. Gel remodeling, biaxial mechanical properties, and collagen orientation were determined after 72 h of culture. Collagen gels contracted spontaneously in the unconstrained direction, uniaxial mechanical constraints produced structural anisotropy, and this structural anisotropy was associated with mechanical anisotropy. Cardiac and tendon fibroblasts were compared to test the hypothesis that tendon fibroblasts should generate greater anisotropy in vitro. However, no differences were seen in either structure or mechanics of collagen gels populated with these two cell types, or between fibroblast populated gels and acellular gels. This study demonstrates our ability to control and measure the development of structural and mechanical anisotropy due to imposed mechanical constraints in a fibroblast-populated collagen gel model system. While imposed constraints were required for the development of anisotropy in this system, active remodeling of the gel by fibroblasts was not. This model system will provide a basis for investigating structure-function relationships in engineered constructs and for studying mechanisms underlying the development of anisotropy in collagenous tissues.
Rhombohedral epitaxy of cubic SiGe on trigonal c-plane sapphire

Abstract Highly [1 1 1]-oriented rhombohedral hetero-structure epitaxy of cubic SiGe semiconductor on trigonal c-plane sapphire was achieved and characterized with two new advanced X-ray diffraction methods to control the formation of primary-twin crystals. The formation of twin crystals on (1 1 1) plane was controlled with growth parameters such that the volume percentage of primary-twin crystal was reduced from 40% to 0.3% compared to the majority single crystal. The control of stacking faults can yield single-crystalline semiconductors without defects or improved thermoelectric materials with twinned crystals for phonon scattering while maintaining electrical integrity. In this study, about 94% of all epitaxial layers were fabricated in a single-crystalline phase. We propose the temperature-dependent alignment model of energetically favored majority single-crystalline SiGe layer on c-plane sapphire. This study shows that nearly single-crystalline cubic semiconductors can be grown in the [1 1 1] orientation on the basal (0 0 0 1) planes of selected trigonal crystal substrates.
On The Pascal Transform and Threshold Selection

The Pascal transform has been introduced recently and it has applications in signal processing and image processing. Applications of the Pascal transform to edge or bump detection often require processing of noisy signals. Since noise can seriously distort the values of the signal transform coefficients, it is important to understand the effects of noise on the Pascal transform of a signal. We focus on evaluating the mean square of the transform coefficients of Gaussian noise and the magnitude of the transform coefficients of the noise. An analytical expression is found for mean square of the transform coefficients of zero mean Gaussian noise. Simulation results are presented for the magnitude of the Pascal transform coefficients of the noise from which models are developed for predicting the magnitude of the transform coefficients. We also present an approach for selecting a threshold to determine a bump using the Pascal transform.
Parietal Area VIP Neuronal Responses to Heading Stimuli Are Encoded in Head-Centered Coordinates

The ventral intraparietal area (VIP) is a multimodal parietal area, where visual responses are brisk, directional, and typically selective for complex optic flow patterns. VIP thus could provide signals useful for visual estimation of heading (self-motion direction). A central problem in heading estimation is how observers compensate for eye velocity, which distorts the retinal motion cues upon which perception depends. To find out if VIP could be useful for heading, we measured its responses to simulated trajectories, both with and without eye movements. Our results showed that most VIP neurons very strongly signal heading direction. Furthermore, the tuning of most VIP neurons was remarkably stable in the presence of eye movements. This stability was such that the population of VIP neurons represented heading very nearly in head-centered coordinates. This makes VIP the most robust source of such signals yet described, with properties ideal for supporting perception.
Regulation of transforming growth factor-β1 by insulin in prediabetic African Americans

Insulin resistance has been associated with kidney disease even in the absence of diabetes; however, pathways linking insulin resistance to kidney disease are unclear. The purpose of this study was to determine if transforming growth factor (TGF)-β1, a key cytokine associated with kidney disease, responds to circulating levels of glucose and/or insulin. Urinary TGF-β1 levels were measured in 249 young adult African Americans (mean age 40) at baseline, after an oral glucose tolerance test and after a euglycemic hyperinsulinemic clamp procedure. Baseline urinary geometric mean TGF-β1 levels were somewhat lower in those with normal compared with the impaired glucose tolerance. The urinary TGF-β1 level increased by 56% followed by a 23% decrease in the normal glucose tolerance group, changes that were significant and corresponded to the changes in the plasma glucose and insulin concentrations. The impaired tolerance group showed little change in the urinary TGF-β1 level following glucose ingestion. All participants had a significant increase in urinary TGF-β1 level after steady-state hyperinsulinemia, with sustained euglycemia during the clamp procedure in both of the groups. At baseline, there was a significant correlation between the urinary TGF-β1 level and urinary albumin excretion. Thus our results suggest that insulin contributes to increased TGF-β1 production and possible early renal injury in prediabetic young African Americans.
Endometrial Hyperplasia with Atypia in an Adolescent with Primary Amenorrhea: A Case Report

Background Endometrial hyperplasia with atypia is an uncommon occurrence in adolescents. It is usually seen in the postmenopausal age range, but it has been reported to be a precursor for endometrial cancer in both premenopausal and postmenopausal patients. Case A 16 year old morbidly obese, hirsute, and developmentally delayed white female presented for evaluation for primary amenorrhea. She received a complete endocrinologic evaluation which showed her to be in the pre-menarchal range with serum estradiol of 1.9 ng/dl, FSH of 8.4 mlu/ml, LH of 5.9 mlu/ml, testosterone of 9.9 ng/dl, DHEA-S of 45 ug/dl, TSH of 1.1 mlu/ml, T3 of 140 ng/dl, Free T4 of 1.0 ng/dl, and prolactin of 21.4 ng/ml. Skull films and a CT of the head were normal. Because she was unable to tolerate any physical exam in the office, she underwent a pelvic exam and transvaginal ultrasound under anesthesia. On pelvic exam, her vaginal mucosa appeared atrophic and slightly friable, but her cervix appeared normal. Her obesity precluded obtaining any information from bimanual exam. The ultrasound showed that she had a thickened endometrium of 1 cm with grossly normal appearing ovaries. The patient then underwent dilation and curettage (D&C) which showed her to have endometrial hyperplasia with focial mild atypia. Medical treatment to reverse the hyperplasia was then planned. Conclusion Endometrial hyperplasia with atypia is a rare event in adolescents since it is usually seen in the postmenopausal age group. This patient presented with primary amenorrhea and was subsequently found to have endometrial hyperplasia with atypia. To the author's knowledge, after extensive review of the literature, this has never previously been reported. Clinicians should be aware of the possibility of atypical endometrial hyperplasia in morbidly obese adolescents with primary amenorrhea.
Human Subjects Research by Business Students: Beyond the Red Tape

Business communication faculty often assign projects that require students to interview, survey, or observe human subjects. Depending on the nature of the project and the policies at the faculty me...
A rotating annular chromatograph for continuous metal separations and recovery

Abstract Multicomponent liquid chromatographic separations have been achieved by using a slowly rotating annular bed of sorbent material. By continuously introducing the feed material to be separated at a stationary point at the top of the bed and eluent everywhere else around the annulus, elution chromatography occurs. The rotation of the sorbent bed causes the separated components to appear as helical bands, each of which has a characteristic, stationary exit point; hence, the separation process is truly continuous. The concept has been developed primarily on a 279-mm-diam by 0.6-m-long device with a 12.7-mm-wide annulus. The effect of annulus width and diameter has recently been studied using the same device with a 50.8-mm-wide annulus and another 0.6-m-long chromatograph with an 89-mm diameter and annulus widths of 6.4, 12.7, and 22.2 mm. These columns have been constructed of Plexiglas and typically operate at a gauge pressure of 175 kPa. To further study the effect of size and pressure, a new 445-mm-diam by 1-m-long column with a 31.8-mm-wide annulus has been fabricated. Its metal construction allows preparative-scale operation with a wide variety of liquids at pressures to 1.3 MPa. Three metal recovery systems have been explored: (i) separation of iron and aluminum in ammonium sulfate-sulfuric acid solutions; (ii) separation of hafnium from zirconium in sulfuric acid solutions; and (iii) the separation of copper, nickel, and cobalt in ammonium carbonate solutions. This last system simulates the leach liquor of the Caron process for recovering nickel and cobalt from laterite ores. It has been studied, using similar conditions, on each of the chromatographs, and the results demonstrate the effect of column dimensions on the quality and quantity of the separation.
Mineralocorticoid Receptor Agonists Induce Mouse Aortic Aneurysm Formation and Rupture in the Presence of High Salt

Objective— Elevated plasma aldosterone concentrations in patients have been linked to a spectrum of cardiovascular diseases. Mineralocorticoid receptor antagonists provide additional benefits in patients with heart failure. However, whether aldosterone and the mineralocorticoid receptor are involved in aortic aneurysm is unknown. Approach and Results— We report that administration of deoxycorticosterone acetate (DOCA) and salt or aldosterone and salt, but not DOCA or salt alone, to C57BL/6 male mice induced abdominal and thoracic aortic aneurysm formation and rupture in an age-dependent manner. DOCA and salt- or aldosterone and salt-induced aortic aneurysm mimicked human aortic aneurysm with respect to elastin degradation, inflammatory cell infiltration, smooth muscle cell degeneration and apoptosis, and oxidative stress. Aortic aneurysm formation did not correlate with the increase in blood pressure induced by DOCA and salt. Systemic administration of the angiotensin-converting enzyme inhibitor, enalapril, or angiotensin type 1 receptor antagonist, losartan, did not affect DOCA and salt-induced aortic aneurysm. In contrast, the mineralocorticoid receptor antagonists, spironolactone or eplerenone, significantly attenuated DOCA and salt- or aldosterone and salt-induced aortic aneurysm. Conclusions— The current study describes a novel aortic aneurysm animal model induced by mineralocorticoid receptor agonist and high salt, and reveals a previously unrecognized but potentially significant role of aldosterone in the pathogenesis of aortic aneurysm. These findings imply that mineralocorticoid receptor antagonists may be effective in the treatment of some aortic aneurysms.
Endurance training increases skeletal muscle LKB1 and PGC-1α protein abundance: effects of time and intensity

Recent research suggests that LKB1 is the major AMP-activated protein kinase kinase (AMPKK). Peroxisome-proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a master coordinator of mitochon...
Two-Player Partnered Exergame for Obesity Prevention: Using Discrepancy in Players' Abilities as a Strategy to Motivate Physical Activity

Background:Physical inactivity is associated with obesity and type 2 diabetes. A key obstacle to physical activity is lack of motivation. Although some interactive exercise games (i.e., exergames—v...