cssi/SciSciGPT-SciSciNet huggingface dataset:
Hydration Kinetics and Microstructure Development of Normal and CaCl2-Accelerated Tricalcium Silicate Pastes

Microstructure development and the kinetics of hydration of pure tricalcium silicate (C3S) and CaCl2-accelerated C3S pastes were investigated by performing isothermal calorimetry and in situ small-angle neutron scattering (SANS) measurements on parallel specimens during the first few days of hydration, as well as on 28-day old specimens hydrated under the same curing conditions (water/cement ratio = 0.5, 20 °C). Calorimetry experiments were also performed over a range of hydration temperatures from 10 to 40 °C. The calorimetry data were analyzed by applying a previously described boundary nucleation and growth model. The model indicates that CaCl2 significantly increases the rate of nucleation of hydration product on the surface of the C3S particles but has relatively little effect on the product growth rate. The SANS measurements indicate that the composition and density of the calcium−silicate−hydrate (C−S−H) nanoparticles is unchanged by the addition of CaCl2. However, in the CaCl2-accelerated paste th...
Lipoxygenase expression in colon polyps and inhibition of colon cancer growth by lipoxygenase blockade

Abstract Introduction: Expression of 5-lipoxygenase (5-LOX) has been shown to be up-regulated in early pancreatic cancer, but has not been characterized in early colon neoplasms. We hypothesize that there is upregulation of 5-LOX in colon polyps and that inhibition of 5-LOX in colon cancer cell lines would inhibit cell growth and induce apoptosis. Methods: Tissue samples of normal colonic mucosa and neoplastic polyps were collected from 20 patients. Immunohistochemistry was used to compare 5-LOX expression between patient's normal colonic mucosa and polyps. Effects of the specific 5-LOX inhibitor, Rev 5901, on cell proliferation were studied in 3 colon cancer cell lines (LoVo, HT-29, HCT-116). Results: Intense 5-LOX staining was evident in polyps from 20/20 specimens. Adjacent areas of normal colonic mucosa did not express 5-LOX. Specific 5-LOX blockade with Rev 5901 showed concentration and time-dependent inhibition of cell proliferation (85% reduction relative to control with 15uM at 24 hours, p Conclusions: These results demonstrate that 1) 5-LOX is up-regulated in colon polyps compared to normal mucosa, and 2) treatment with 5-LOX inhibitor Rev 5901 results in decreased cell proliferation and increased apoptosis. These findings provide evidence that 5-LOX plays a role in colon cancer development and may be an early target for chemoprevention of colon cancer.
Assessment of a current and optical confinement in operational quantum well laser

Abstract Confinement of electrons and holes is assumed to take place within the quantum well of a laser diode for all modes of operation of the diode. Photons are expected to be confined within the Fabry–Perot cavity with little spreading out of the resonator. After it was established that the quasi-Fermi (QF) profile across an operational laser defines the concentration of carriers in a quantum well, this new study was initiated in order to establish correlation between the shape of the QF profile and the degree of optical and current confinement. The quantum well based laser diodes consist of p- and n-doped layers of Al 0.6 Ga 0.4 As sandwiching two undoped layers of Al 025 Ga 0.75 As 0.16 μm thick which, in turn, surround two layers of 150 A GaAs in which the 110 A In 0.2 Ga 0.8 As quantum well is encased. This structure was mounted in a scanning electron microscope (SEM), and differential voltage contrast (DVC) was used to measure QF profiles while intensity of emission was measured by a specially calibrated photoamplifier. We observed very high peaks of QF energy, which could be explained on the basis of photon interaction with hole and electron gasses. In the current study, we were able to assess, in-situ, the QF profile for the population inversion, the threshold of laser operation, and full emission, as well as the degree of confinement at these stages of laser diode operation.
A transient study of the co-adsorption and reaction of CO and oxygen on Ir(110)☆

Abstract The heterogeneously catalyzed reaction of CO and O2 to form CO2 over Ir(110) has been studied through measurements of the transient kinetics of the various elementary reactions that may limit the steady state rate. Rate expressions for these elementary reactions — the desorption of CO, the oxidation of CO via the Langmuir-Hinshelwood mechanism, the adsorption of CO and the adsorption of oxygen — were developed using thermal desorption mass spectrometry. Several phenomena were observed: (1) the activation energies for CO desorption and CO oxidation depend markedly upon the composition of the adlayer; (2) diffusion in the adlayer may limit the rates of CO desorption and CO oxidation; (3) the formation of a surface oxide modifies these four rate processes; and (4) chemisorbed CO blocks sites for oxygen adsorption, but chemisorbed oxygen does not block sites for CO adsorption.
Thin-plate theory for large elastic deformations

Abstract Non-linear plate theory for thin prismatic elastic bodies is obtained by estimating the total three-dimensional strain energy generated in response to a given deformation in terms of the small plate thickness. The Euler equations for the estimate of the energy are regarded as the equilibrium equations for the thin plate. Included among them are algebraic formulae connecting the gradients of the midsurface deformation to the through-thickness derivatives of the three-dimensional deformation. These are solvable provided that the three-dimensional strain energy is strongly elliptic at equilibrium. This framework yields restrictions of the Kirchhoff–Love type that are usually imposed as constraints in alternative formulations. In the present approach they emerge as consequences of the stationarity of the energy without the need for any a priori restrictions on the three-dimensional deformation apart from a certain degree of differentiability in the direction normal to the plate.
Leiomyoma-related hospitalization and surgery: prevalence and predicted growth based on population trends

Objective To estimate leiomyoma-related inpatient care in the United States for 2007 with predictions for the ensuing 40 years. Study Design We used the 2007 Nationwide Inpatient Sample to estimate hospitalizations and inpatient surgeries for uterine leiomyoma in US women 15 to 54 years. We used the US Census Bureau population projections to predict leiomyoma-related inpatient care through 2050. Results In 2007, 355,135 women were hospitalized for leiomyoma (rate = 42 per 10,000 women-years). Black women had increased rates of hospitalization, hysterectomy, and myomectomy (relative risk, 3.5, 2.4, 6.8, respectively) compared with white women. Leiomyoma-related hospitalizations are predicted to increase 23% (to 437,874) between 2007 and 2050, with 20% and 31% increases in leiomyoma-related hysterectomies and myomectomies. Conclusion Leiomyoma-related inpatient care and major surgery remains substantial despite advances in less invasive treatment options. Given population growth, the projected burden of leiomyoma-related inpatient care will increase significantly by 2050, differentially impacting black vs white women.
Spontaneous verbal labeling: visual memory and reading ability in children with cleft.

Abstract Objective: The purpose of this study was to examine different types of short-term memory deficits (visual versus verbal) of children with cleft and to determine what type of memory deficits were associated with reading disorders. Design: The study examined memory and reading in 48 consecutive cases of children with cleft, aged 7 to 9 years. A memory test designed to assess memory modalities (verbal-visual) was administered, along with tests of reading ability. Results: Visual and verbal memory were examined with a one-way analysis of variance (ANOVA). The memory pattern indicated greatest deficit in visual memory. Two subgroups were formed, according to whether or not there was evidence of visual memory impairment. A hit rate predicting reading disability based on group membership was calculated to be 65%. Visual memory was significantly correlated with reading ability (r = .48). Conclusion: A brief visual memory test was almost as good as Full Scale IQ in predicting reading disability.
Is Giselle a virgin

In his book The Ballet Called Giselle, Cyril W. Beaumont expresses a degree of puzzlement over an important plot development, one which has also bothered other observers: Giselle's remarkably sudden descent into fatal madness on discovering she has been deceived by Albrecht. "Quick temper and poor health might explain her frenzy and her tears," he observes, but what should cause "madness to result from what at worst is no more than a bitter disappointment? " His answer is a bit weak. He concludes that "Giselle must
Modeling of the Nucleation and Growth of Domain Needles

Some recent results on phase-field modeling of the nucleation, growth and interaction of domain needles are presented. First, the nucleation of domains near crack tips is studied within the context of a small-scale switching boundary layer formulation. Combinations of mechanical stress intensity factors and electric displacement intensity factors that cause domain nucleation are reported. After nucleation, domains are allowed to grow. The effects of the new domain structures on the crack growth energy release rate are studied.Copyright © 2010 by ASME
Integration in small steps: The European commission and member‐state aid to industry

Member states of the European Union traditionally have used a variety of aids to industry to develop national champions, rescue major enterprises in financial trouble, and to make industry more competitive internationally. Yet making the single European market operational and sustaining cohesion across member states with different abilities to aid their industrial enterprises requires that the European Commission monitor state aid closely. Most accounts of this tension point to the weak record of the Commission in rejecting aid packages proposed by member states. This article argues that the rate of rejection of aids by the Commission is a highly misleading indicator of the Commission's influence in this policy area. In fact, the Commission has developed substantial capacities to regulate state aid relative to the constraints within which it operates.
Abstract 568: Biomarkers of phenethyl isothiocyanate-mediated mammary cancer prevention in MMTV-neumouse model

Biomarker(s) predictive of efficacy is necessary for clinical development of promising cancer chemopreventive agents because cancer incidence is too rigorous of an end point for malignancies with long latency such as breast cancer. The present study was undertaken to identify biomarker(s) associated with phenethyl isothiocyanate (PEITC)-mediated mammary cancer prevention in MMTV-neu transgenic mouse model. The PEITC is a promising cancer chemopreventive constituent of cruciferous vegetables (e.g., watercress). Two-dimensional gel electrophoresis-mass spectrometry of tumor specimens from control and PEITC-fed mice (n= 3) revealed alterations in expression of several proteins, including hexokinase-1, isoform CRA_f (1.36-fold increase by PEITC administration), L-lactate dehydrogenase A chain isoform 1 (1.57-fold increase by PEITC administration), pyruvate kinase isozymes M1/M2 (1.33-fold decrease by PEITC administration), and mitochondrial ATP synthase, H + transporting F1 complex beta subunit (1.38-fold decrease by PEITC administration). Interestingly, the PEITC-induced apoptotic cell death in cultured cancer cells is associated with inhibition of oxidative phosphorylation leading to production of reactive oxygen species. Down-regulation of mitochondrial ATP synthase protein in tumors of PEITC-fed mice was confirmed by immunohistochemistry. Expression of mitochondrial ATP synthase was reduced by about 66% in the tumors from PEITC-fed mice in comparison with control (P= 0.05 by two-sided Student9s t-test, n= 6-7). In addition, plasma level of transthyretin was significantly higher in the PEITC treatment group compared with control (P= 0.04 by two-sided Student9s t-test, n= 5). In conclusion, the present study not only underscores the power of proteomics in cancer chemoprevention research but also suggests that mitochondrial ATP synthase, and possibly hexokinase-1, pyruvate kinase isozymes M1/M2, and/or L-lactate dehydrogenase A chain isoform 1, may be useful biomarkers to assess the biological activity of PEITC in future clinical trials. This study was supported in part by the US PHS grants CA101753 and CA129347, awarded by the National Cancer Institute. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 568. doi:1538-7445.AM2012-568
Studies of metabolism in embryonic development. VI. Cortisol-binding proteins of trout embryos.

Abstract 1. 1. A stable and an unstable Cortisol-protein binding complex were isolated from the cytosol of rainbow trout embryos. 2. 2. The binding protein of the major stable complex had a molecular weight of 50,000; the protein had high specificity for Cortisol; the association constant K of the binding complex was 2 × 10 11 M −1 . 3. 3. The binding complex isolated from the nuclear fraction of the embryos had the same sedimentation velocity in a sucrose gradient as the major binding component of the cytosol. 4. 4. The minor unstable component was present in both the cytosol of the embryos and in the blood plasma of the adult trout.
Saturated 13.2 nm high-repetition-rate laser in nickellike cadmium

We report gain-saturated operation of a 13.2?nm tabletop laser in Ni-like Cd at a 5?Hz repetition rate. A gain–length product G×L=17.6 was obtained by heating a precreated plasma with 8?ps duration Ti:sapphire laser pulses with an energy of only 1?J impinging at a grazing angle of 23°. With an average power of ?1??W, this laser is an attractive coherent source for at-wavelength metrology of extreme UV lithography optics and other applications.
Comparative features of retroviral infections of livestock

Abstract Retrovial infections of livestock have become of increasing importance due to their usefulness as comparative models for human retroviral infections and their effects upon animal health and marketability of animals and animal products nationally and internationally. This paper presents a perspective on the retroviruses of economic concern in veterinary medicine with emphasis on the importance of understanding the modes of virus transmission and the species specificity of the viruses. The retroviruses reviewed include the oncovirus, bovine leukosis virus, and the lentiviruses, equine infectious anemia virus; maedi/visna virus, caprine arthritis-encephalitis virus and bovine visna-like virus. The comparative features amongst these animal retroviruses and those of humans must be recognized by the veterinary and medical professions since the similarities in virus replication and spread by blood transfer can provide important clues in controlling and perhaps preventing human retroviruses infections, such as the human immunodeficiency virus.
Comparative study of Gaussian basis sets for calculation of core electron binding energies in first-row hydrides and glycine

A number of Gaussian basis sets has been studied for performance in density functional calculations of core electron binding energies and chemical shifts of the carbon, nitrogen, and oxygen nuclei in the first-row hydrides methane, ammonia, and water, and in glycine. The ultimate goal is to identify methods sufficiently accurate and efficient to aid analysis of experimental X-ray photoelectron spectra for amino acids, large polypeptides, and DNA nucleosides in various environments. Several combinations of density functionals and basis sets have been identified as promising for such calculations with average accuracy of 0.20 eV or better.
On social laws for artificial agent societies: off-line design

Abstract We are concerned with the utility of social laws in a computational environment, laws which guarantee the successful coexistence of multiple programs and programmers. In this paper we are interested in the off-line design of social laws, where we as designers must decide ahead of time on useful social laws. In the first part of this paper we suggest the use of social laws in the domain of mobile robots, and prove analytic results about the usefulness of this approach in that setting. In the second part of this paper we present a general model of social law in a computational system, and investigate some of its properties. This includes a definition of the basic computational problem involved with the design of multi-agent systems, and an investigation of the automatic synthesis of useful social laws in the framework of a model which refers explicitly to social laws.
AN EVOLUTIONARY APPROACH TO MATHEMATICS EDUCATION: ENHANCING LEARNING THROUGH CONTEXTUAL MODIFICATION*

ABSTRACT Contemporary mathematics education is at a crossroads. It has become exposed to forces, both static and dynamic, that pose a challenge to its traditional place in academia. Mathematics has a long-established status as perhaps the most critical foundation for analytical knowledge. But the manner in which mathematics instructors choose to respond to this challenge may well determine the degree of relevance and importance that traditional mathematical theory eventually commands in newly emerging scientific and technological disciplines. In this paper, we will: (a) identify the forces that are acting on contemporary mathematics instruction; (b) examine some of the historical, social, and psychological underpinnings that have given rise to these forces; (c) enumerate the conditions which mathematics instruction must address if it is to remain a viable discipline; and (d) evaluate the relative success of a case study, addressing the role of mathematics instruction for technical career students, that ha...
Effects of prolonged entanglement in discarded fishing gear with substantive biofouling on the health and behavior of an adult shortfin mako shark, Isurus oxyrinchus

A mature male shortfin mako, Isurus oxyrinchus, was captured with a three-strand twisted natural fiber rope wrapped around the body causing deep abrasions, scoliosis of the back, and undernourishment. Fifty-two pelagic peduculate barnacles from four species were found fouling on the rope. Assuming larval settlement occurred following entanglement, barnacle growth-rate data suggest the rope had been around the shark for at least 150 days. However, the onset of severe scoliosis (likely linked to the increased constriction of the rope with growth and the added drag induced by biofouling) indicates that this rope may have been in place much longer. Following removal of the rope, a pop-up satellite archival tag was attached to the shark to assess post-release health. The resulting 54 days of tag deployment data show that despite its injuries, the shark survived, and following an initial stress period, exhibited movement patterns characteristic of healthy makos.
Do individual crocodilians adjust their signaling to habitat structure

All crocodilians use long-distance signals, composed of infrasound, vocal sounds and/or slaps. These components differ in their ability to carry information about the animal's location and status through air and water. It has been previously shown that signal composition differs between species and allopatric conspecific populations; species and populations living in fragmented aquatic habitats use more vocal signals and/or fewer slaps than species and populations living in continuous aquatic habitats, thus adjusting their signaling to habitat structure. There are two possible mechanisms for such adjustment: behavioral plasticity and evolved differences between species and populations. In the present study, it is shown (a) that individual yacare caimans (Caiman yacare) do not change the composition of their signals in response to changes in aquatic habitat continuity, and (b) that in areas where both continuous and fragmented aquatic habitats are available, American alligators (Alligator mississippiensis)...
Prognostic relevance of karyometric and histometric features of malignant tumors

In contrast to cytophotomnetric studies of nuclear detail quantitative inorphomnetry of histologic specimens has only been developed to a limited degree as a diagnostic tool /13/. Counting of mnitoses is one of the oldest methods for quantification and has become a valuable predictor of good or poor prognosis of uterine soft tissue tumors /5/. In case of malignant melanoma the determination of tumor thickness has proven an important prognostic factor /4/. Measurements of endometrial gland volume enable the pathologist to discriminate endomnetrial carcinoma from hyperplasia /1/2/. Other applications of mnorphometry to special diagnostic problems could be added /13/. L© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A Model for Dynamic Fracture

It is shown that the dynamic fracture criterion for metals is equivalent to the failure criterion of a Voigt body containing a non-Newtonian dashpot. Integration of the differential equation leads to the concept of a critical incubation time for fracture. Contrary to static fracture criteria, not only is a sufficiently high stress necessary but this stress has also to be present for a sufficiently long time, so that large stresses afford small duration and vice versa. Some consequences of the dynamic fracture law are applied to dynamic metal behaviour at elevated temperatures, as well as to the size of the shock loaded material.
Identifying and evaluating information technology bachelor's degree programs

This paper describes the process for identifying and evaluating Information Technology (IT) bachelor’s programs in the United States, in an effort to answer the question, how many IT bachelor’s programs are there in the US? Due to widespread variation in the names of academic degree programs, one cannot simply count those named Information Technology. At SIGITE 2011, a framework was presented for identifying IT programs and for evaluating their compliance to an accepted standard. This framework has been applied throughout this research. We first compiled a list of prospective IT programs to research. Each university on the list was researched by looking at their university webpage in search of a list of computing majors listed at that university. If, at a glance, these program’s required courses look similar to those required in an IT program, the program was evaluated and given a numerical score compliance factor, as compared to the standard, no matter the name of the major. This compliance factor is calculated using the assessment form that is included in this document. The results of this analysis are presented. General Terms Computing Programs, Information Technology
The Virtue of Patience: Offloading Topical Cellular Content through Opportunistic Links

Mobile data offloading is an approach to alleviating overloaded cellular traffic through alternative communication technologies on smartphones. Inspired by the prospect of spontaneous, peer-assisted, bulk data transfer through NFC or Wi-Fi Direct between proximate users' smartphones, we propose a model for mobile data offloading through the opportunistic proximity (e.g., Wi-Fi Direct) links with bounded content delivery delay and differential interests in content. Unlike the previous formulation of mobile data offloading as a target-set selection problem, which, essentially, asks the question "who (will download the content through the cellular link)," we ask "who" and "when." We present methods for individual users to locally estimate (their and their acquaintances') topological importance on the opportunistic proximity-link-based networks and aggregated interests in content. These factors are consolidated into a time-dependent function that embodies the concept of users' patience for the content. Each individual user, then, periodically make a probabilistic cellular download decision based on its patience at that time. Our motivation and insights are: 1) Involving topologically important, but otherwise disinterested, users in downloading and forwarding content helps improve offloading efficiency, 2) situation awareness embodied in the time-dependent patience function is desirable, since it allows users to react to hard-to-predict contact opportunities on the fly. Through trace-driven simulations, we corroborate our insights, and demonstrate the effectiveness of our proposed method in reducing cellular costs.
Analysis of Ignition and Flame Spreading in Solid Rocket Motor Star Slots

Introduction T HE ignition transient of a solid rocket motor (SRM) employing a pyrogen igniter can be defined as the time interval from the onset of the igniter flow to the time a quasisteady flow develops. A little-understood portion of the starting transient for (star) slotted head-end grain configurations is the time interval encompassing the initiation of the igniter flow, the first appearance of a flame on the star grain, and the subsequent flame spread over the star slot region. Previous analyses' for motors such as those used on the Space Shuttle agree quantitatively well with test data, except for the time period that directly involves burning of the headend star grain segment. Discrepancies during this time period are believed to arise from three factors: 1) the flowfield is assumed to be one-dimensional, 2) the star geometry in the head-end segment is approximated by variations in port area and grain burning perimeter, and 3) the igniter flowfield is not accounted for. The authors have previously presented a numerical calculation method utilizing the time-dependent, two-dimensional Navier-Stokes equations, which calculates the subsonic flow induced in the slot by the supersonic igniter plume. The focus of the present study is the calculation of the initial portion of the ignition transient, beginning with the start of igniter flow and ending when the head-end star slot segment of the motor is fully burning. The expanding igniter plume, the complex flow patterns within the star slot, heat transfer to the propellant grain, and subsequent propellant burning are considered.
Ultrasonography for detection of pregnancy and study of embryonic development in heifers

Real-time B-mode ultrasonography was used to evaluate uterine changes associated with the estrous cycle in 22 ovulatory periods in 12 nulliparous heifers. Irregular, nonechogenic (black) areas were seen on the images of uterine horns during the periovulatory period. These nonechogenic areas were presumably due to intraluminal fluids since they coincided with the discharge of clear, viscous mucus preceding ovulation and blood-tinged mucus after ovulation. Eight heifers were bred until five pregnant heifers were obtained for study of the ultrasonic morphology of the conceptus. Ultrasound examinations were done daily to day 50 of pregnancy. Discrete, nonechogenic areas were first visible within the uterus between days 12 and 14, when they were approximately 2 mm in diameter. These discrete nonechogenic structures were identified as the embryonic vesicle, since they were observed only in heifers later confirmed to be pregnant and were always in the uterine horn ipsilateral to the corpus luteum. The presence of an embryo within the embryonic vesicle was confirmed by observing an echogenic (white) area with rhythmic pulsations (heartbeat). The embryonic vesicle gradually increased in length from the day of first observation until day 26 when it extended past the curvature of the horn and began to encroach into the contralateral horn. In all heifers, by day 32 the vesicle extended to the tip of the contralateral horn. The embryo was first visible between days 26 and 29 when the mean length was 10 mm. The embryo increased in length an average of 1.1 mm per day. A heartbeat was detectable in the embryo on the first day observed. In one superovulated heifer, five vesicles were visible in the uterine horns by day 14 and by day 33 seven embryos were observed; two of the seven embryos apparently resorbed by day 43.
Children under the age of two are more likely to watch inappropriate background media than older children

Emerging data suggests that the impact of electronic media exposure on young children's cognitive and psychosocial development varies, depending upon whether the programme content is in the foreground or background. Programming that is designed for young children (child-directed), comprehensible to the child and watched by the child is referred to as “foreground” programming (1). Programming that is not produced for children (not child-directed), not comprehensible and not watched by the child is referred to as “background”. While foreground exposure is adversely associated with attention, cognition and language outcomes (2-6), background exposure interferes with parent–child interactions (7-10) and the quantity and quality of play (11-12). Given the different impacts of foreground and background media exposure on child development outcomes, it would be useful to understand the circumstances in which children do or do not watch programming to which they are exposed. Prior studies have suggested that the child's age, whether the content of the programme is intended for a child and whether it has been chosen by the parents play a role in determining general exposure and, in particular, predict whether the child watches the programme (13-17). Limitations of prior studies have included: i) lack of a well-defined differentiation between foreground and background media exposure and ii) the use of cross-sectional study designs, in which change over time could not be assessed. In addition, previous studies have focused primarily on patterns of media exposure in middle-income and high-income children, so we don't know whether similar factors influence patterns of media exposure in low-income populations who may be at greatest risk for adverse developmental consequences. The need to develop a better understanding of foreground and background media was recently highlighted in a study that documented that the greatest amount of background exposure occured among children under the age of two years from low-income families (18). The gap in knowledge regarding what children watch and don't watch has complicated efforts to determine degree of exposure as well as the impact of foreground and background media exposure. We therefore sought to address this gap by studying patterns of exposure in a low-income sample of children who were followed longitudinally. We had two hypotheses. The first was that children would be more likely to watch programming as they got older and when the programming was specifically aimed at them. The second was that younger children were likely to watch a greater proportion of media that were not intended for them.
Detection and Determination of p-Coumaroylated Units in Lignins

The derivatization followed by reductive cleavage (DFRC) method cleaves α- and β-ethers in lignins but leaves lignin γ-esters intact. When applied to grasses, which contain p-coumarate esters on their lignins, esterified monolignol derivatives are released. Saturation of the p-coumarate double bond occurs during DFRC, so the released products are 4-acetoxycinnamyl 4-acetoxyphenylpropionates. Synthesis of the esters allowed determination of response factors for the released products. Maize and bamboo lignins released 221 and 38 μmol/g of p-coumarate-derived esters. The sinapyl ester was much more abundant than the coniferyl one. The bamboo and maize lignin S/G ratios in the conjugates were 12 and 38 times greater than those of the normal monomers released by DFRC, evidence of a strong selectivity for acylation of syringyl units. Of three possible biochemical mechanisms for incorporating p-coumarates into lignin, evidence is mounting that the process involves incorporation of preacylated monolignols into th...
User resistance determinants and the psychological contract in enterprise system implementations

User resistance is an important issue in the implementation of enterprise systems (ES). However, despite a large body of user acceptance literature, there is far less literature addressing user resistance. This study seeks to better understand the development of user resistance. Information is obtained and triangulated in this study from a focus group and semi-structured user interviews from three organizations. Through the lens of the psychological contract employees have with their organization, user resistance is investigated. Twelve determinants were found that upset the psychological contract and affect the level of user resistance. These determinants have been classified into four key categories which expand on previous literature: individual, system, organizational, and process issues. The relationships among these concepts and both the theoretical and practical contributions of this study are discussed.
Systematics of Isospin Mixing in Proton Elastic Scattering from Light Nuclei

The effects of isospin mixing observed by isospin-forbidden resonant proton scattering from the stable, self-conjugate, even-even nuclei exhibit a simple dependence on target mass number $A$. Furthermore, for $A=8n+4$, $n$ integral, the mixing is systematically a factor of 5 larger than for $A=8n$ The relation between this behavior and the trends of other relevant nuclear properties is discussed.
THE EFFECT OF SOLVENT POLARITY ON THE CONDENSATION OF HYDROLYZED TETRAETHYLORTHOSILICATE IN MICROEMULSION GELS

ABSTRACT A study of the condensation of hydrolyzed tertaethylorthosilicate (TEOS) was conducted to investigate the influence of solvent polarity. A non-aqueous microemulsion was formed to which was added water (pH 1) and TEOS. The various condensation products were observed with 29Si NMR of systems of differing amounts of formamide and decanol/decane at increasing time intervals. The solvent polarity of the solvent system was found to clearly influence the initial and final rates of condensation, despite the fact that the specific condensed moieties were the same in each of the systems studied.
Transports in the Duluth-Superior Harbor

A hydrodynamic model and a water quality model for the Duluth-Superior harbor are developed and verified by using data on currents, water levels, and water quality parameters. The water quality model is subsequently used to simulate the transport of particulates resuspended by ship traffic and the dispersal of dissolved material spilled into the harbor at a major industrial site. Resuspension of bottom sediments by ship traffic is an important secondary source of harbor turbidity. Suspended solids in ship resuspension plumes range from 10 to 50 mg/L, five times the usual concentration of suspended solids in the harbor. An estimated 105 kg of material is resuspended per passage of a ship. The resuspended material is coarse and settles rapidly, thus only 0.1% of the material flows out directly into Lake Superior. Most of the material resuspended by ship traffic is redistributed to the low turbulence areas within the shipping channels. It was found that a spill of dissolved pollutant in the inner harbor would take from 8 to 21 days to reach Lake Superior at peak concentrations. The peak concentration of pollutant at the lake entries depends on seiche amplitude and ranges from 0.05 to 0.1% of the initial concentration at the spill site. At a 0.1% concentration level, the spill would extend over 30% of the harbor, and would remain in the harbor for 30 to 40 days.
Some kinetic and chromatographic properties of detergent-dispersed adenylate cyclase.

Studies on the reaction kinetics and chromatographic properties of detergent-dispersed adenylate cyclase are described. Detergent-dispersed enzyme was prepared from whole rat cerebellum and from partially purified plasma membranes from rat liver. Data were simulated to fit kinetic models for which an inhibitor is added in constant proportion to the variable substrate. Models were chosen to distinguish whether the adenylate cyclase reaction may be controlled by an inhibitory action of free ATP−4 (or HATP−3) or by a stimulatory action of free divalent cations. The various kinetic models were then tested with the dispersed brain adenylate cyclase with both Mg++ and Mn++ and in two different buffer systems. The experimental data indicate that this enzyme has a distinct cation binding site, but exhibits no significant inhibition by HATP−3 or ATP−4. The detergent-dispersed adenylate cyclase both from liver plasma membranes and from brain have been chromatographed on anion exchange material and have been chromatographed on anion exchange material and have been subjected to gel filtration. The presence of detergent was required for elution of cyclase activity from DEAE-Sephadex but was not required when DEAE-agarose was used. Dispersed brain cyclase was also chromatographed on agarose-NH(CH2)3 NH(CH2)3-NH2 which exhibits both ionic and hydrophobic properties. Fifty percent of the applied activity was recovered with a fivefold increase in specific activity. The data suggest that the relative effectiveness of a given chromatographic procedure for detergent-dispersed adenylate cyclase may reflect the in fluence of both hydrophobic and ionic factors.
Chemical and morphological evolution in Parmelia sect. Hypotrachyna: Product of ancient hybridization?

Nineteen species ofParmelia sect.Hypotrachyna that contain either barbatic acid or evernic acid and other related compounds fall into four major chemical types based upon biogenetic consideration of their secondary products. The major chemistries show clear correlations with geography, but groups based upon morphological characters do not. The origin of the present-day species can be explained by ancient hybridizations of chemically different types and subsequent parallel morphological evolution.
Eigenvector method for maximum-likelihood estimation of phase errors in synthetic-aperture-radar imagery

We develop a maximum-likelihood (ML) algorithm for estimation and correction (autofocus) of phase errors induced in synthetic-aperture-radar (SAR) imagery. Here, M pulse vectors in the range-compressed domain are used as input for simultaneously estimating M − 1 phase values across the aperture. The solution involves an eigenvector of the sample covariance matrix of the range-compressed data. The estimator is then used within the basic structure of the phase gradient autofocus (PGA) algorithm, replacing the original phase-estimation kernel. We show that, in practice, the new algorithm provides excellent restorations to defocused SAR imagery, typically in only one or two iterations. The performance of the new phase estimator is demonstrated essentially to achieve the Cramer–Rao lower bound on estimation-error variance for all but small values of target-toclutter ratio. We also show that for the case in which M is equal to 2, the ML estimator is similar to that of the original PGA method but achieves better results in practice, owing to a bias inherent in the original PGA phase estimation kernel. Finally, we discuss the relationship of these algorithms to the shear-averaging and spatial correlation methods, two other phase-correction techniques that utilize the same phase-estimation kernel but that produce substantially poorer performance because they do not employ several fundamental signal-processing steps that are critical to the algorithms of the PGA class.
Keck Interferometer: from development phase to facility-class instrument

The Keck Interferometer is entering a regular limited observational phase. A restricted number of observers are expected to use the instrument over the course of the next few years in a shared-risk capacity. To facilitate this, the W. M. Keck Observatory and the Jet Propulsion Laboratory are following a Handover procedure consisting of a number of stages related to the science modes of the instrument as they reach completion. The first of these is the Visibility Science mode that involves only the two Keck telescopes. Other modes to follow are Nulling, Differential Phase, Astrometry, and Imaging. The process includes defining a reasonable level of functionality of each mode, training observatory staff to maintain and schedule tasks related to the upkeep of each mode, and defining and documenting each of the subsystems related to each mode. Here we discuss the outline of the Handover plan and report on its progress to date.
Radiosensitivity of different B and T subpopulations of lymphocytes in the mouse spleen.

X-irradiation was used as a tool to investigate the radiosensitivity of different B and T precursor subpopulations as detected by three in vitro culture systems. The culture systems utilized in this study included antigen reactive cell assays (ARCA), polyclonal mitogen assays (PMA), and polyclonal effector cell assays (PECA). The order of radiosensitivity of these systems in both the B and T cell series was ARCA>PMA>PECA (D37 values for B cell responses: ARCA=88.8 R, PMA=125 R, PECA=223 R; D37 values for T cell responses: ARCA=160 R, PMA=441 R and PECA=1095 R). With all assay systems the B cell response was more radiosensitive than the T cell response. The extrapolation number (n) from the radiation survival curves was approximately 2.0 for T cell responses and approximately 1.0 for B cell responses. The value of 1.0 for B cell responses suggest that their extreme radiosensitivity may be due in part to a lack of repair mechanisms. These findings also suggest that the more primitive precursor cells are more apt to undergo cellular proliferation upon activation and that this event is more radiosensitive than is the final differentiation event of precursor cells into a progeny of functional end-stage cells.
Desert-dwelling Mountain Sheep: Conservation Implications of a Naturally Fragmented Distribution

: Mountain sheep (Ovis canadensis) are closely associated with steep, mountainous, open terrain. Their habitat consequently occurs in a naturally fragmented pattern, often with substantial expanses of unsuitable habitat between suitable patches; the sheep have been noted to be slow colonizers of vacant suitable habitat. As a result, resource managers have focused on (1) conserving “traditional” mountainous habitats, and (2) forced colonization through reintroduction. Telemetry studies in desert habitats have recorded more intermountain movement by desert sheep than was previously thought to OCCUT. Given the heretofore unrecognized vagility of mountain sheep, we argue that existing corridors of “nontraditional” habitat connecting mountain ranges be given adequate conservation consideration. Additionally, small areas of mountainous habitat that an? not permanently occupied but that may serve as “stepping stones” within such corridors must be recognized for their potential importance to relatively isolated populations of mountain sheep. We discuss the potential importance of such corridors to other large, vagile species. Resumen: Los borregos cimarrones (Ovis canadensis) exhi-ben una asociacion cercana con terrenos montanosos escar-pados y abiertos. En consecuencia, su habitat ocurre en un patron naturalmente fragmentado, frecuentemente con grandes extensiones de habitat impropio separando las areas apropiadas; y se ha notado gue los borregos cimarrones son lentos en colonizar habitat apropiado vacante. Como resultado de estes observaciones, gerentes de recursos naturales ban enfocado su atencion en (1) constrvacion de habitat montanoso “tradicional” y (2) colonizacion forzado por reintroduccion. Estudios telemetricos en habitates desiertos ban demostrado mas movimiento entre sierras que antes se creia que ocurria. Dado la tendencia de vagar basta abora no reconocido de los borregos cimarrones, proponemos que corredores actuales de habitat no tradicional que conectan sierras merecen consideracion adecuada para consmacion. Ademas, se debe reconocer la importancia para poblaciones relativamente aisladas de los borregos cimarrones de areas pequenas de habitat montanoso que, aunque no ocupadas de manera permanente, pueden facilitar el movimiento de los borregos cimarrones dentro de dichos corredores. Se senala la importancia de estos cowedores para ohos especies errantes grandes.
Imitation and expression of facial affect in autism

This study examined elicited (posed) affective expressions in children, adolescents, and young adults with autism (N = 18) or Down's syndrome (N = 24). Subjects were asked to (a) imitate five modeled expressions (Imitation task) and (b) produce five labeled expressions (Expression task). Subjects with autism produced recognizable expressions in both tasks, but they produced fewer than did subjects with Down's syndrome when target emotions were labeled but not modeled (Expression). Imitation and Expression tasks were equally difficult for subjects with autism, but subjects with Down's syndrome performed better in Expression than in Imitation. In both tasks, the responses of subjects with autism contained many unusual behaviors, such as bizarre expressions and those that looked “mechanical.” Results suggest that producing elicited affective expressions is more difficult for persons with autism than for persons with Down's syndrome of similar chronological age, mental age, and IQ.
Conformational States of the Nuclear Pore Complex Induced by Depletion of Nuclear Ca2+ Stores

The nuclear pore complex (NPC) is essential for the transit of molecules between the cytoplasm and nucleoplasm of a cell and until recently was thought to allow intermediate-sized molecules (relative molecular mass of approximately 10,000) to diffuse freely across the nuclear envelope. However, the depletion of calcium from the nuclear envelope of Xenopus laevis oocytes was shown to regulate the passage of intermediate-sized molecules. Two distinct conformational states of the NPC were observed by field emission scanning electron microscopy and atomic force microscopy. A central plug occluded the NPC channel after nuclear calcium stores had been depleted and free diffusion of intermediate-sized molecules had been blocked. Thus, the NPC conformation appears to gate molecular movement across the nuclear envelope.
Depression Vulnerability Moderates the Effects of Cognitive Behavior Therapy in a Randomized Controlled Trial for Smoking Cessation

Several clinical trials have tested the hypothesis that smoking cessation treatments with a mood management component derived from cognitive behavior therapy (CBT) for depression would be specifically effective for depression-vulnerable smokers, with mixed results. This trial addressed methodological concerns with some of the previous studies to clarify whether depression vulnerability does in fact moderate CBT smoking cessation outcome. The study compared 8-session group CBT with a time-matched comparison group condition in a sample of 100 cigarette smokers randomized to treatment condition. Each treatment group was led by one of 7 American University clinical psychology graduate students; therapists were crossed with treatment conditions. Outcome (7-day point prevalence abstinence) was evaluated 1 month and 3 months after quit date. Baseline self-reported depression vulnerability (sample median split on the Depression Proneness Inventory) moderated treatment response, such that more depression-prone smokers fared better in CBT whereas less depression-prone smokers fared better in the comparison condition. These results may have implications for determining when to use CBT components in smoking cessation programs.