cssi/SciSciGPT-SciSciNet huggingface dataset:
The discursive coding of software: a study of the relationship between stability and change

Software has become an integral part of most people's everyday lives. Though discussions of software in the field of rhetoric have traditionally taken an instrumentalist approach that seeks to increase the effective use of software, a critical turn has established the need to examine the ideological signification of software. I argue that one way we can do so is to examine the social practices that symbolically constitute software to reveal how software is discursively coded, and how, consequently, users of software are themselves discursively coded. To this end, I examine the discourse of those primarily responsible for the design and regulation of software---the software programming culture. To analyze the discourse of the software programming culture, I developed a spatio-temporal framework rooted in theories of practice and theories of space and time to guide both my choice of data and the methods by which I conduct analyses. In attempting to resist the objectivist/subjectivist dualism that so often limits accounts of how meaning is made through social practices, I employ historical, ideological, and genre analysis to contextualize and analyze the discourse of the software programming culture. My goal is to identify, describe, and map a network of meaning that simultaneously allows for stability and change. I argue that this network of meaning constitutes not just software but also the software programming culture as a discursive site of ideological struggle, the effects of which have significance for society as a whole. Unveiling the process by which software, as a technological and culture artifact, is discursively coded is a move toward digital literacy that is important for understanding the ways in which ideologies are embedded in the discourse of technological artifacts. In the case of software, I argue that such an understanding may allow even the least technologically-adept users to interrupt and challenge their own coding as digital subjects by the software programming culture and to cultivate a digital literacy that empowers users to have a voice in how their own lives are affected by the discursive coding of software.
Comparison of thrombospondin-1 type I repeats anti-angiogenic therapy with gemcitabine in an orthotopic pancreatic cancer model

Proc Amer Assoc Cancer Res, Volume 46, 2005 3036 Introduction: Pancreatic cancer is the fourth leading cause of cancer deaths in the United States. We hypothesized that an anti-angiogenic domain of thrombospondin-1 (TSP-1), the three type I repeats (3TSR), can be used to reduce tumor burden of mice with orthotopic pancreatic cancer. Anti-tumor efficacy of 3TSR was compared to gemcitabine controls. Methods: An orthotopic mouse model of human pancreatic cancer was developed using intrapancreatic injection of human pancreatic cancer cells (AsPC-1). One week after tumor implantation, mice were treated with 3TSR (n=9, 3 mg/kg/day), gemcitabine (n=6, 150 mg/kg, biweekly) or the combination of the two drugs (n=11) for 3 weeks. Control mice (n=11) received equivalent volume of phosphate buffered saline. The effects of 3TSR and/or gemcitabine on tumor volume, tumor necrosis, microvessel density (CD31), pancreatic cancer cell proliferation (PCNA), apoptosis (TUNEL) and tumoral endothelial cell apoptosis (CD31T combination 10%). AsPC-1 tumors treated with 3TSR showed reductions in both blood vessel number and average area, and 3TSR significantly decreased tumor microvessel density (MVD) (3.13%, control 7.69%, p<0.05). Gemcitabine treatment resulted in a moderate decrease in MVD (5.72%, p<0.05 vs. control), and the MVD of tumors from mice treated with 3TSR plus gemcitabine was 3.76%. The apoptotic rates of tumoral endothelial cells were significantly increased after 3TSR treatment (13.43%, control 3.72%, p<0.0001), while 3TSR showed no effects on pancreatic cancer cell proliferation or apoptosis. In contrast, gemcitabine had moderate effects on tumoral endothelial cell apoptosis (7.11%), but significantly inhibited tumor cell proliferation (9.05% vs. control 19.23%, p<0.001) and induced tumor cell apoptosis (19.19% vs. control 5.27%, p<0.001). Conclusion: Anti-angiogenic therapy with 3TSR significantly reduced tumor volume and vascular density in mice with orthotopic pancreatic tumors, and may prove to be an effective novel treatment for human pancreatic cancer.
Ergodic Algorithms on Special Euclidean Groups for ATR

This paper describes a technique for estimating motions of rigid targets based on the deformable template representations of complex scenes. The efficient modeling of representations for variabilities manifested by objects, shapes and scenes supporting invariant recognition is crucial. There are several kinds of variabilities fundamental to these representations: (i) the variability in target pose and placement, and (ii) variability in target numbers and identities. To model the first variability, templates are constructed from two-dimensional CAD surfaces representing the rigid objects. Using the deformable template approach, these templates are varied via the basic rigid transformations involving the translation and rotation groups. Since complex scenes are composed of multiple moving targets, the complete scene transformations are finite Cartesian products of these Lie groups. Given a set of observations of a particular scene the inference constitutes generating minimum mean squared error (MMSE) estimates and, hence, optimizing on the curved geometry of Lie manifolds.
Attitudes of general education teachers toward including students with special needs

Due to the recent push towards inclusion, many students with special needs are finding themselves in the general education classroom. Research has shown that students’ success in classes is affected by their teachers’ attitudes towards having them in there. This study takes a closer look at high school general education teachers’ attitudes, in the state of Iowa, towards working with students with special needs in the general education classroom.
Gingival cysts; report of three cases.

Abstract Three cases of clinically and roentgenologically discernible gingival cysts have been described. Such lesions should be considered not only in the classification of cysts, but also in the differential diagnosis of radiolucent lesions of the jaws.
Effect of Nonequilibrium Grain Boundary Segregation of Alloying Elements on Mechanical Properties in Fe–5Mn–9Ni–5Mo Alloy

Nonequilibrium grain boundary segregation of alloying elements in an Fe-5Mn-9Ni-5Mo alloy and its effect on the mechanical properties have been investigated through AES and tensile test. The alloy showed a ductile-brittle-ductile transition during isothermal aging at 430 or 450°C, and intergranular fracture was shown in the brittle region. This transition was due to manganese segregation to the grain boundaries and its desegregation into the matrix, and was deeply related to the precipitation reaction of fct MnNi. The segregation level of manganese showed a peak value with aging time which corresponded to the lowest ultimate tensile strength, but the segregation level of nickel at the grain boundaries steadily increased with no peak level. This was due to the interaction coefficient between nickel and molybdenum in longer aging times, which augmented the free energy of segregation of nickel. In longer aging times, molybdenum participating in the precipitation reaction of Fe 2 Mo at the grain boundaries or in the bulk acted as a potent strengthener of the grain boundaries. The segregation level of molybdenum increased to a saturation value due to the interaction between nickel and molybdenum.
Direct-to-Patient Laboratory Test Reporting: Balancing Access With Effective Clinical Communication

In February 2014, the Department of Health and Human Services (HHS) issued a landmark ruling allowing patients direct access to completed medical laboratory reports.1 The ruling took effect April 7, 2014, and gives laboratories 180 days from that date to comply. Although this recent change to the Clinical Laboratory Improvement Amendments (CLIA) empowers patients by removing access barriers to personal health information, it raises a variety of clinical and ethical questions involving practitioners, patients, and society. To capture the benefits of the change and to minimize potential challenges, clinicians will need to proactively counsel patients to ensure that patients do not engage in detrimental self-interpretation of test results, especially because of the abundance of information and misinformation made available through the Internet and other sources.2
Electron-phonon interaction in double-barrier resonant tunneling.

The electron-phonon-assisted tunneling in a quantum-well double-barrier structure is studied within the transfer-Hamiltonian approach. It is found that as the bias voltage increases, the tunneling current exhibits, besides the normal resonant peak, a series of small resonances when a magnetic field is applied along the direction of the tunneling current. These small resonant structures are attributed to the coupling of electrons with optical phonons. In the present study, two modes are considered: (a) electrons interact with phonons in the quantum well, resulting in additional structures in the electron density of states; (b) electrons couple with barrier phonons, introducing inter-Landau-level tunneling events. Our calculations may help to explain recent experimental observations.
Steal This Courseware: FOSS, Github, Python, and OpenShift (Abstract Only)

This workshop introduces participants to the pedagogy and practice of using Free/Open Source Software development practices into their curriculum, and then guides them through deployment of a turnkey courseware framework to be used for their own courses. The framework supports automatic blog checking, automatically generated student profile pages, Gravatar integration for profile pictures, Travis-CI continuous Integration tests, and repository changes reported via Github webhooks to IRC. Participants will learn how to use Github in the Classroom, the basics of Flask, a python web framework, and how to deploy their courseware to Red Hat's OpenShift Cloud, a free Platform-as-a-Service to host courseware and/or other web sites.
TEMPERATURE MEASUREMENTS OF HOT GAS STREAMS

Temperature measurement of equilibrium, nonradiating, hot gas streams by determining heat transfer rate using probe techniques
Serotonergic projections to the spinal cord from the midbrain in the rat: An immunocytochemical and retrograde transport study

Neurons localized in the midbrain nucleus raphe dorsalis and caudal midbrain reticular formation have direct projections to the cervical spinal cord in the rat. By means of double labeling technique, using the retrograde cell marker horseradish peroxidase and immunocytochemistry, 90% of these spinally projecting neurons were positively stained for serotonin immunoreactivity. These results indicate that serotonergic innervation of the spinal cord is provided not only by the medullary cell groups B1-B3, but also by the midbrain cell groups B7 and B9.
Comparison of dry-etch techniques for GaN, InN, and AlN

FABRICATION OF GROUP III NITRIDE DEVICES RELIES ON THE ABILITY TO PATTERN FEATURES TO DEPTHS RANGING FROM 1000 A TO {gt} 5 MICRONS WITH ANISOTROPIC PROFILES, SMOOTH MORPHOLOGIES, SELECTIVE ETCHING OF ONE MATERIAL OVER ANOTHER, AND A LOW DEGREE OF PLASMA INDUCED DAMAGE. IN THIS STUDY, GAN ETCH RATES AND ETCH PROFILES ARE COMPARED USING REACTIVE ION ETCH (RIE), REACTIVE ION BEAM ETCHING (RIBE), ELECTRON CYCLOTRON RESONANCE (ECR), AND INDUCTIVELY COUPLED PLASMA (ICP) ETCH SYSTEMS. RIE YIELDED THE SLOWEST ETCH RATES AND SLOPED ETCH PROFILES DESPITE DC-BIASES {gt} -900 V. ECR and ICP etching yielded the highest rates with anisotropic profiles due to their high plasma flux and the ability to control ion energies independently of plasma density. RIBE etch results also showed anisotropic profiles with slower etch rates than either ECR or ICP possibly due to lower ion flux. InN and AlN etch characteristics are also compared using ICP and RIBE.
Denjoy minimal sets are far from affine

Not every Cantor set can arise as the minimal set for a C^1 diffeomorphism of the circle. For example, McDuff has shown that the usual ‘middle thirds’ Cantor set cannot arise in this way. In this paper we exclude a suitable neighborhood of the class of affine Cantor sets.
Enzyme activities in regenerating epithelium during wound healing. IV. Aminotransferases and NADP-dependent enzymes.

Abstract Alanine aminotransferase activity decreased gradually in marginal and regenerating epithelium during the first 4 days of wound healing. A decreasing gradient of alanine aminotransferase activity was observed from the marginal epithelium to the migrating epithelial tip; the actively migrating epithelial tip exhibited only 10% of normal activity. In contrast to alanine aminotransferase activity, aspartate aminotransferase activity increased slightly and did not exhibit a significant differential distribution gradient within regenerating epithelium. The epithelium at the wound margin exhibited three-fold increases in glucose-6-phosphate dehydrogenase and malic enzyme activities, little alteration in 6-phosphogluconate dehydrogenase activity, and a 30% decrease in isocitrate dehydrogenase activity, together with an increased NADPH concentration. Regenerating epithelium demonstrated a five-fold increase in glucose-6-phosphate dehydrogenase and malic enzyme activities and a 60% increase in 6-phosphogluconate dehydrogenase and isocitrate dehydrogenase activities, together with an elevated level of NADPH concentration.
Detection and characterization of human tissue lesions with near-infrared Raman spectroscopy

Near infrared (NIR) Raman spectroscopy provides a powerful method for quantitative histochemistry of human tissue and disease diagnosis. The feasibility and potential of this technique for in situ histochemical analysis of human coronary artery has been demonstrated and presented in other reports from our laboratory. In this work, we review recent results obtained with the NIR Raman spectroscopy on a variety of tissue types studied at the MIT Laser Biomedical Research Center. We have collected NIR Raman spectra from colon, bladder, breast, and carotid artery. For colon, bladder and breast, consistent differences between carcinoma and normal tissue spectra were observed. For colon and bladder, the spectral differences appear to be due to an increased content of nucleic acid in carcinomas, while the spectral changes in malignant breast tissue are associated with an increase of protein content. Spectra from carotid artery have similar features as those from aorta and coronary arteries. We also show some preliminary results obtained with a NIR Raman microspectroscopy setup with 20 micron lateral resolution. The biochemical distributions for normal and diseased regions on the same tissue samples are observed. The potential of using this NIR Raman spectroscopy for detection and characterization of carcinoma and atherosclerosis, is discussed.
Resveratrol inhibits the epithelial sodium channel via phopshoinositides and AMP-activated protein kinase in kidney collecting duct cells.

Resveratrol, a naturally occurring phytoalexin, has reported cardioprotective, anti-inflammatory, chemopreventative and antidiabetic properties. Several studies indicate the multiple effects of resveratrol on cellular function are due to its inhibition of class 1A phosphoinositide 3-kinase (PI3K) mediated signaling pathways, but it also activates AMP-activated protein kinase (AMPK). As sodium transport in the kidney via the Epithelial Sodium Channel (ENaC) is highly sensitive to changes in phosphoinositide signaling in the membrane and AMPK, we employed resveratrol to probe the relative effects of phosphatidylinositol species in the plasma membrane and AMPK activity and their impact on ENaC activity in mouse cortical collecting duct (mpkCCDc14) cells. Here we demonstrate that resveratrol acutely reduces amiloride-sensitive current in mpkCCDc14 cells. The time course and dose dependency of this inhibition paralleled depletion of the PI(3,4,5)P3 reporter (AKT-PH) in live-cell microscopy, indicating the early inhibition is likely mediated by resveratrol's known effects on PI3K activity. Additionally, resveratrol induces a late inhibitory effect (4–24 hours) that appears to be mediated via AMPK activation. Resveratrol treatment induces significant AMPK activation compared with vehicle controls after 4 h, which persists through 16 h. Knockdown of AMPK or treatment with the AMPK inhibitor Compound C reduced the late phase of current reduction but had no effect on the early inhibitory activity of resveratrol. Collectively, these data demonstrate that resveratrol inhibits ENaC activity by a dual effect: an early reduction in activity seen within 5 minutes related to depletion of membrane PIP3, and a sustained late (4–24 h) effect secondary to activation of AMPK.
Notch signaling in melanoma: interacting pathways and stromal influences that enhance Notch targeting

Summary The Notch signaling pathway is an evolutionarily conserved, intercellular signaling cascade. Notch was first described in the early 1900s when a mutant Drosophila showed notches on the wing margins. Studies of the role of Notch signaling have ever since flourished, and the pleiotropic nature of the Notch gene is now evident. Indeed, the Notch signaling pathway plays key roles in cell fate decisions, tissue patterning, and morphogenesis during development. However, deregulation of this pathway can contribute to cell transformation and tumorigenesis. Several reports have now highlighted the role of Notch signaling in a variety of malignancies where Notch can either be an oncogene or a tumor suppressor depending on the cell context. Here, we summarize the major components of Notch signaling with an aim to emphasize the contribution of deregulated Notch signaling in melanomagenesis.
The Measurement of Teaching Efficiency

(1921). The Measurement of Teaching Efficiency. The Journal of Educational Research: Vol. 4, No. 2, pp. 81-93.
Role of Stearoyl-CoA Desaturase-1 in Skin Integrity and Whole Body Energy Balance

The skin is the single largest organ in humans, serving as a major barrier to infection, water loss, and abrasion. The functional diversity of skin requires the synthesis of large amounts of lipids, such as triglycerides, wax esters, squalene, ceramides, free cholesterol, free fatty acids, and cholesterol and retinyl esters. Some of these lipids are used as cell membrane components, signaling molecules, and a source of energy. An important class of lipid metabolism enzymes expressed in skin is the Δ9-desaturases, which catalyze the synthesis in Δ9-monounsaturated lipids, primarily oleoyl-CoA (18:1n-9) and palmitoyl-CoA (16:1n-7), the major monounsaturated fatty acids in cutaneous lipids. Mice with a deletion of the Δ9-desaturase-1 isoform (SCD1) either globally (Scd1−/−) or specifically in the skin (skin-specific Scd1-knockout; SKO) present with marked changes in cutaneous lipids and skin integrity. Interestingly, these mice also exhibit increased whole body energy expenditure, protection against diet-induced adiposity, hepatic steatosis, and glucose intolerance. The increased energy expenditure in skin-specific Scd1-knockout (SKO) mice is a surprising phenotype, as it links cutaneous lipid homeostasis with whole body energy balance. This minireview summarizes the role of skin SCD1 in regulating skin integrity and whole body energy homeostasis and offers a discussion of potential pathways that may connect these seemingly disparate phenotypes.
Influence of surfactant on rounded and pointed bubbles in two-dimensional stokes flow

A simple plane flow model is used to examine the effects of surfactant on bubbles evolving in slow viscous flow. General properties of the time-dependent evolution as well as exact solutions for the steady state shape of the interface and distribution of surfactant are obtained for a rather general class of far-field extensional flows. The steady solutions include a class for which "stagnant caps" of surfactant partially coat the bubble surface. The governing equations for these stagnant cap bubbles feature boundary data which switches across free boundary points representing the cap edges. These pointsare shown to correspond to singularities in the surfactant distribution, the location and strength of which are determined as part of the solution. Our steady bubble solutions comprise shapes with rounded as well as pointed ends, depending on the far-field flow conditions. Unlike the clean flow problem, we find in all cases an upper bound on the strain rate for which steady solutions exist. A possible conne...
Prostate-Specific Antigen Testing Practices and Outcomes

OBJECTIVES: To characterize prostate-specific antigen (PSA) testing practices in a hospital-based primary care clinic, and to determine the outcomes of PSA testing, including urology referrals, biopsies, cancers detected, and cancer treatments.
Abstract A104: Involvement of FOXO1 in E2/ER pathway and tamoxifen resistance in MCF-7 cells

Introduction: Estrogen receptor positive breast tumors frequently become resistant to Tamoxifen therapy. Elucidating mechanisms that contribute to resistance are critical for developing therapeutic targets. Previously, we have shown in our lab that FOXO1, a pro-apoptotic transcription factor, plays a role in Trastuzumab resistance, and is inactivated in Her2-overexpressing tumors associated with increased AKT activation. Restoration of FOXO1, both by inhibiting the AKT pathway and by FOXO1 transfection, restored cell-sensitivity to Trastuzumab. Currently, we are exploring whether FOXO1 may play a similar role in resistance to Tamoxifen in ER positive breast cancer cells. We hypothesize that loss of function of FOXO1 may contribute to Tamoxifen resistance and reactivation may restore sensitivity to tamoxifen. Methods: We have generated two tamoxifen resistant clones and in addition have studied a Tamoxifen resistant clone called MCF-7 TAMR/HER2 (HER2-transfected). tamoxifen resistant clones were generated by passaging wildtype MCF-7 (WT) cells through sphere cultures in the presence of tamoxifen. These clones are termed MCF-7 TAMR7 and MCF-7 TAMR26, representing 7 and 26 passages in sphere culture respectively. Cell line characteristics were assayed by immunohistochemistry (IHC) and RT-Q-PCR. Furthermore, MTT assays were used to test for E2 response in WT and TAMR cells. Results: Tamoxifen resistance was acquired by utilizing the sphere assay in the presence of Tamoxifen. IHC results revealed a significant loss of ER receptor in TAMR7 and TAMR26 clones. RT-Q-PCR demonstrated 85% loss of ER receptor mRNA in the TAMR7 and TAMR26 compared to WT cells. There was no difference in ER expression in WT and TAMR/HER2 cells. KI67 and CyclinD1 expression were lower in TAMR (TAMR7 and TAMR26) cells compared to WT and TAMR/HER2 cells. TAMR26 cells had lower proliferative response to E2 compared to WT cells. There was increased expression of CK5 in TAMR26 cells. FOXO1 was phosphorylated and located in the cytoplasm of the TAMR cells (TAMR7 and TAMR26) compared to WT and TAMR/HER2 cells. Conclusions: This study demonstrates that one mechanism of Tamoxifen resistance may be through the loss of the Tamoxifen target, the estrogen receptor (ER). TAMR clones isolated from mammosphere cultures with long term Tamoxifen treatment acquire an ER negative phenotype. These cells demonstrate loss of function of FOXO1. In addition, TAMR cells with high HER2 and normal ER, also acquire Tamoxifen resistance, by mechanisms not clearly understood. Further studies are currently underway in our lab to explore these mechanisms. Citation Information: Cancer Epidemiol Biomarkers Prev 2010;19(10 Suppl):A104.
Examining the time course of prime effects on Stroop processing.

This study was conducted to assess the effect of priming on the Stroop task over time. Color-congruent, color-incongruent, and neutral stimuli were randomly presented. Five prime conditions were also used. The prime conditions included valid color, invalid color, valid word, and invalid word primes and no prime. Primes were presented to 8 subjects at varying stimulus onset asynchronies ranging from -200 msec., i.e., 200 msec, before the color-word stimulus, to 200 msec, i.e., 200 msec, after the color-word stimulus. Analysis suggested the facilitory or inhibitory effects of semantic information on the Stroop task are reduced when the prime follows the color-word stimulus by 200 msec. This implies 200 msec. are needed to make the proper color response. A model is proposed to account for the findings. Methodological considerations for studies using priming and the Stroop task are also discussed.
Speech behavior and social evaluation: An examination of medical messages

Three levels of speech rate and pitch variation were used in audio‐taped presentations of two medical messages varying in seriousness of illness (high and low). The messages were uttered in natural speech samples which listeners judged according to their perceptions of rate and pitch as well as personality traits. A personality structure emerged which included dynamism, social attractiveness, and professional competence. Rate had its largest effects on dynamism while pitch variation had a greater influence on social attractiveness and professional competence. Seriousness of illness was primarily involved in interaction effects, the most important of which involved interaction between seriousness of illness and rate. High rate was perceived as less professionally competent in the high serious illness condition than the low serious condition, while medium rate yielded the highest ratings of professional competence for the high serious illness. The results are discussed in the framework provided by the dimen...
Kiloparsec-Scale Motions in 3C 120—Revisited

Walker, Walker, & Benson reported the detection of superluminal motion on kiloparsec scales in 3C 120, a source with well-studied superluminal motion on parsec scales. This result was based on twoepoch observations of a knot in the jet 4'' from the core using the VLA at 5 GHz. Muxlow & Wilkinson attempted to confirm this motion using 1.67 GHz observations with MERLIN, but instead got a result consistent with no motion and inconsistent with the earlier VLA result at about the 2 σ level. Third-epoch VLA observations by Walker & Benson also produced the result of no motion between epochs 2 and 3, for which the images were superior to that of epoch 1. Fourth-epoch VLA observations were made in 1996 November. The results, along with a reanalysis of the earlier epochs, are presented here. It is now clear that the 4'' knot is moving much more slowly than the parsec scale features, if at all. The observation of superluminal motion is good evidence for relativistic motions near the line of sight in a jet. This is important information for the understanding of jet physics. The observation of lack of motion, on the other hand, does not say much about the jet velocity. It might suggest that the jet is not relativistic. However, a number of effects in a relativistic jet, including standing shocks and fortuitous bends, could also lead to stationary features. As a by-product of these observations, an extremely high dynamic range image of the 3C 120 jet on scales to 25'' was produced and is discussed briefly.
Amino acids (natural and synthetic) as influencing hemoglobin production in anemia.

We wish to submit evidence that histidine and phenylalanine (both natural and synthetic forms) may under certain conditions exert a definite influence upon the regeneration of red cells and hemoglobin in standardized dogs made anemic by blood withdrawal. We have been accumulating experimental data relating to the influence of various amino acids by mouth upon hemoglobin production and hope to publish a report in the near future.Many of the dogs used had been under observation for more than 6 to 8 years continuously anemic and carefully standardized with liver, iron and other food factors. In these dogs upon the experimental regimen recently described1 fluctuation of 10 gm. hemoglobin production per 2-week period may come within physiological limits but fluctuations of 20 gm. hemoglobin or over have significance. It will be noted in Tables I and II that an increase in hemoglobin output above the basal control levels associated with amino acid feeding may amount to 25-50 gm. hemoglobin per 2-week period. Th...
Molecular motional and structural study of ammoniated titanium disulfide by proton NMR

Abstract Proton spin-lattice relaxation times and linewidths have been measured as a function of temperature at 25 MHz for (NH4+)0.21Ti20.21− and at 25 and 50 MHZ for (NH4+)0.22(NH3)0.37TiS20.22−. In the former compound, the NH4+ cations reorient randomly and rapidly on trigonal prismatic sites in the van der Waals gap of TiS2, and there is no evidence of other thermally activated motion between 3 K and the deintercalation temperature. In the latter compound, two distinct types of motions can be discerned from their characteristic NMR signals. At lower temperatures the NH3 molecules rotate about their three-fold axes and above 270 K translational diffusion occurs. An average proton-proton distance of 1.79±0.03 A in NH3 has been evaluated from the temperature dependence of the relaxation time associated with the C3 axis rotation. This large distance relative to that in normal pyramidal NH3 (1.65 A) is consistent with a planar NH3 geometry and perhaps some lengthening of the normal NH bond length (1.008 A). The activation energy for NH3 rotation (2.41 ± 0.02 kcal/mol NH3) is nearly equal to that measured in solid NH3 (2.3 kcal/mol NH3). A high-temperature minimum in the relaxation time has been attributed to NH3 diffusion, with an activation energy (13.3±3kcal/mol NH3) that is in good agreement with the NH3 deintercalation enthalpy.
Estimating the effect of unit-based pricing in the presence of sample selection bias under Japanese Recycling Law

Abstract In Japan the Containers and Packaging Recycling Law requires the collection of recyclable packaging and containers. In particular, municipalities are required to collect and store the containers and packaging that households have separated from solid waste. However, the law has non-binding standards, and some municipalities do not provide collection services for these recyclables. When estimating the substitution effect of unit-based pricing, i.e. the substitution of recyclables for solid waste, missing data for those municipalities that do not provide a collection service will lead to a truncated sample and, therefore, a sample selection bias in the estimators. We use a Type 2 Tobit model to correct a bias which arises because of missing data. This model provides a consistent estimator, and shows that a higher price for bags and tags increases recycling by households under the unit-based pricing systems introduced by municipalities.
The total synthesis of (±)bakkenolide-A

Recently several examples of a new class of eremophilane sesquiterpenes have been isolated from Petasites japonicus of which bakkenolide-A (1) is a representative member.2'3 As a consequence ofourinterest in stereoselective [2,3] sigmatropic processes,4 we felt that the structurally interesting Spiro-B-methylene-y-lactone moiety contained in 1 could be readily constructed via such molecular rearrangements. Herein we wish to report the stereoselective synthesis of (+)-bakkenolide-A (1) employing a new lactone spiroannelation reaction sequence.
Adjustments for Rater Effects in Performance Assessment

Alternative methods to correct for rater leniency/stringency effects (i.e., rater bias) in per formance ratings were investigated. Rater bias effects are of concern when candidates are evaluated by different raters. The three correction methods evaluated were ordinary least squares (OLS), weighted least squares (WLS), and imputation of the missing data (IMPUTE). In addition, the usual procedure of averaging the observed ratings was investigated. Data were simulated from an essentially τ-equivalent measure ment model, with true scores and error scores nor mally distributed. The variables manipulated in the simulations were method of correction (OLS, WLS, IMPUTE, averaging the observed ratings), amount of missing data (50% missing, 75% missing), rater bias (low, high), and number of examinees or can didates (N = 50, N = 100). The accuracy of the methods in estimating true scores was assessed based on the square root of the average squared difference between the estimated and known true scores. The three cor...
Iron, hemochromatosis, and hepatocellular carcinoma

Hereditary hemochromatosis (HH) is associated with an increased risk for hepatocellular carcinoma (HCC). The risk previously had been estimated to be as high as 200-fold increased. Recent studies suggest that the risk for HCC in HFE-associated HH may be much lower and occurs predominantly in patients with cirrhosis at the time of diagnosis. The risk for HCC also is increased among patients with African iron overload and possibly in other iron-loading disorders such as homozygous β thalassemia. The greatly increased iron stores in the liver observed in these disorders can stimulate carcinogenesis via both direct and indirect pathways. The prevalence of HCC also appears to be higher among patients with end-stage liver disease undergoing liver transplantation. It is not clear whether mildly to moderately increased hepatic iron stores or HFE mutations are associated independently with an increased risk for HCC among patients with other types of liver disease. In this article, the incidence and prevalence of HCC in patients with HH and other liver diseases associated with iron overload are discussed as well as the possible mechanisms for the increased risk for hepatic carcinogenesis in these disorders.
Action Potential and Contractility Changes in [Na+]i Overloaded Cardiac Myocytes: A Simulation Study

Sodium overload of cardiac cells can accompany various pathologies and induce fatal cardiac arrhythmias. We investigate effects of elevated intracellular sodium on the cardiac action potential (AP) and on intracellular calcium using the Luo-Rudy model of a mammalian ventricular myocyte. The results are: 1) During rapid pacing, AP duration (APD) shortens in two phases, a rapid phase without Na(+) accumulation and a slower phase that depends on [Na(+)](i). 2) The rapid APD shortening is due to incomplete deactivation (accumulation) of I(Ks). 3) The slow phase is due to increased repolarizing currents I(NaK) and reverse-mode I(NaCa), secondary to elevated [Na(+)](i). 4) Na(+)-overload slows the rate of AP depolarization, allowing time for greater I(Ca(L)) activation; it also enhances reverse-mode I(NaCa). The resulting increased Ca(2+) influx triggers a greater [Ca(2+)](i) transient. 5) Reverse-mode I(NaCa) alone can trigger Ca(2+) release in a voltage and [Na(+)](i)-dependent manner. 6) During I(NaK) block, Na(+) and Ca(2+) accumulate and APD shortens due to enhanced reverse-mode I(NaCa); contribution of I(K(Na)) to APD shortening is negligible. By slowing AP depolarization (hence velocity) and shortening APD, Na(+)-overload acts to enhance inducibility of reentrant arrhythmias. Shortened APD with elevated [Ca(2+)](i) (secondary to Na(+)-overload) also predisposes the myocardium to arrhythmogenic delayed afterdepolarizations.
A limit to TDC turbulence intensity in internal combustion engines

The turbulence level near top dead center (TDC) in an internal combustion engine strongly influences the flame propagation and the combustion processes. The effect of intake system design on TDC turbulence has recently been studied experimentally. This paper presents comparisons of the predictions of a model for the turbulent flowfields with those experimental data taken in a ported engine with and without swirl and in a valved engine without swirl. The model is for an axisymmetric geometry and uses a k-t submodel for turbulent transport. The model constants are the same as those used in several previous studies. The computed results show fairly good agreement with the measurements. The two-dimensional results are also compared with those from a zero-dimensional model and serious limitations of the zero-dimensional model are evidenced. The twodimensional calculations lead to the important conclusion that there is an upper limit to the magnitude of the TDC turbulence intensity in reciprocating engines with pancake combustion chambers. This limit is independent of the characteristics of the flowfield at the end of the intake processes and is due to the chamber walls. Below the limit, TDC turbulence intensity is influenced primarily by the turbulent diffusivity of the gas at the end of the intake process.
E Pluribus Unum: Arguments against Conceptual Schemes and Empirical Content

The idea that there are conceptual schemes, relative to which we conceptualize experience, and empirical content, the nonconceptual (and so purely causal) "raw" data of experience that get conceptualized through our conceptual schemes into beliefs or sentences, is not new. The scheme-content dualist par excellance was Kant, and in the twentieth century the logical positivists formulated the dualism in terms of linguistic frameworks (or "languages") and sense-data. Quine himself, though rejecting the positivists' characterization of linguistic frameworks as sets of analytic sentences, nonetheless continued to distinguish what he calls 'language', embodying our set of concepts, from 'extralinguistic facts', the raw data of experience. On this view a conceptual scheme would be the total system of concepts and, so, the epistemic agent's total contribution to the truth of beliefs and sentences; understood linguistically, a conceptual scheme would be the total linguistic contribution to doxastic and sentential truth. Empirical content would then be the total nonconceptual content given by the world itself and, so, the world's total contribution to doxastic and sentential truth—the total ej:^ralinguistic contribution to such truth. Nonetheless Quine argued that, though "[i]t is obvious that truth in general depends on both language and extralinguistic fact" (1951, 36), this "double dependence ... is not significantly traceable into the statements ... taken one by one" (42, my emphasis throughout).^ Instead, according to Quine, "language" or "scheme" is dispersed holistically throughout all the sentences of a theory.
SIMMONDS’ DISEASE ASSOCIATED WITH PERNICIOUS ANEMIA, WITH BIOASSAY OF LARGE CHROMO-PHOBE ADENOMA

THE VITAL ROLE of physiologic fundamentals in the advancement of knowledge of certain problems in clinical medicine is well illustrated by the remarkable progress in the field of endocrine medicine during recent years. For example, pituitary tumors have been recognized pathologically since the time of Morgagni (1), and their clinical symptoms were anticipated as early as 1850 by Orr (2), Aber-crombie (3), Zenker (4) and others, but the first evi’ dence of the far'reaching influence of the pituitary gland awaited the early experiments of the late Harvey Cushing (5). These important contributions presaged the first description of the clinical syndrome of pituitary deficiency by Simmonds (6) in 1914.
MOIL-opt: Energy-Conserving Molecular Dynamics on a GPU/CPU system.

We report an optimized version of the molecular dynamics program MOIL that runs on a shared memory system with OpenMP and exploits the power of a Graphics Processing Unit (GPU). The model is of heterogeneous computing system on a single node with several cores sharing the same memory and a GPU. This is a typical laboratory tool, which provides excellent performance at minimal cost. Besides performance, emphasis is made on accuracy and stability of the algorithm probed by energy conservation for explicit-solvent atomically-detailed-models. Especially for long simulations energy conservation is critical due to the phenomenon known as “energy drift” in which energy errors accumulate linearly as a function of simulation time. To achieve long time dynamics with acceptable accuracy the drift must be particularly small. We identify several means of controlling long-time numerical accuracy while maintaining excellent speedup. To maintain a high level of energy conservation SHAKE and the Ewald reciprocal summation are run in double precision. Double precision summation of real-space non-bonded interactions improves energy conservation. In our best option, the energy drift using 1fs for a time step while constraining the distances of all bonds, is undetectable in 10ns simulation of solvated DHFR (Dihydrofolate reductase). Faster options, shaking only bonds with hydrogen atoms, are also very well behaved and have drifts of less than 1kcal/mol per nanosecond of the same system. CPU/GPU implementations require changes in programming models. We consider the use of a list of neighbors and quadratic versus linear interpolation in lookup tables of different sizes. Quadratic interpolation with a smaller number of grid points is faster than linear lookup tables (with finer representation) without loss of accuracy. Atomic neighbor lists were found most efficient. Typical speedups are about a factor of 10 compared to a single-core single-precision code.
Elastic properties of glasses.

It is believed that covalent glasses can be divided into two classes: those with high average coordination (amorphous solids) and those with low average coordination (polymeric glasses). We present the first conclusive evidence that this division is correct by calculating the elastic properties of random networks with different average coordination $〈r〉$. The results show that the elastic constants depend predominantly on $〈r〉$ and go to zero when $〈r〉=2.4$ with an exponent $f=1.5\ifmmode\pm\else\textpm\fi{}0.2$.
Sequestration and Segregation of Receptor Kinases in Epithelial Cells: Implications for ErbB2 Oncogenesis

Cell behaviors are regulated by signaling pathways triggered by the activation of cell surface receptors. A key aspect of receptor signaling is the location of these receptors relative to their ligands and to other receptors, particularly in epithelia, whose cells are polarized by tight junction barriers into apical and basolateral membrane regions. In polarized epithelia, the co-receptor ErbB2 is often localized to the apical surface by its intramembrane ligand Muc4, thus segregating it from its partner ErbB3, which is sequestered at the lateral surface, co-localized with cadherin junctions. The ErbB2-ErbB3 receptor heterodimer, when activated, is a potent stimulator of cell proliferation; thus, the segregation mechanism helps maintain these cells in a differentiated state. Similarly, epidermal growth factor, the ligand for ErbB1, which is present in the apical fluid of some epithelia, is segregated from its receptor by the tight junction barrier. Loss of cell polarity and the tight junction barrier facilitates the interaction of ErbB2 with the hemidesmosome integrin α 6 β 4 . This integrin acts as a docking site for signaling pathways to promote cell proliferation and further disruption of cell junctions. The ultimate dissolution of tight junctions may result from activation of transforming growth factor–β receptors, one subunit of which is directly associated with the junction. This activation triggers degradation of critical tight junction components. These sequestration and segregation phenomena provide a model by which overexpression of the ErbB2 receptor kinase may trigger oncogenesis by initiating junction breakdown. Equally important, these mechanisms may act as a sensor for epithelial damage that can activate repair mechanisms.
Human Issues in Human Rights.

The National Academy of Sciences' Committee on Human Rights and its 350 correspondent academy members seeks to ease the plight of individual scientists, engineers, and medical personnel suffering severe repression. It has engaged in a program of private inquiry, public remonstrance, and moral support in behalf of individuals from 11 countries. In developing this activity, members of the committee had to engage in a series of troubling issues related to the nature of human rights, the choice of cases, and the format of protest. But most troubling of all are the issues raised by the profound distortions of humanness, nationhood, and science that follow in the wake of repression.
The Changing Face of Head and Neck Cancer in the 21st Century: The Impact of HPV on the Epidemiology and Pathology of Oral Cancer

The longstanding notion that head and neck squamous cell carcinoma (HNSCC) is a uniform disease process is changing. Divergence in epidemiologic trends among HNSCCs arising in different anatomic subsites has introduced a view that HNSCC is a heterogeneous group. Analysis of molecular genetic changes discloses not just individual tumor differences, but also consistent large-scale differences that permit the recognition of important tumor subtypes. One recently recognized subtype is the human papillomavirus (HPV)-positive oropharyngeal carcinoma. HPV-positive oropharyngeal cancer now dominates the head and neck oncology landscape, and its escalating incidence is impacting on diagnostic, preventive and therapeutic practices.
Assignments with the Computer

The current job market favors young technical writers who are skilled in the way of the computer both as a subject of writing and as a production tool. In the technical writing classroom students c...
Purification and characterization of pyruvate ferredoxin oxidoreductase from the hyperthermophilic archaeon Pyrococcus furiosus.

Abstract Pyrococcus furiosus grows optimally at 100°C by carbohydrate fermentation. It is thought to contain a novel tungsten-dependent, NAD(P)-independent glycolytic pathway in which one of the oxidation steps is catalyzed by a tungsten-containing aldehyde ferredoxin oxidoreductase. The enzyme that catalyzes the terminal oxidation step, pyruvate ferredoxin oxidoreductase (POR), has now been purified. POR has a molecular mass of 100 kDa and is comprised of three subunits (45, 31 and 24 kDa). It lacks tungsten but contains thiamine pyrophosphate (TPP) and two ferredoxin-type [4Fe-4S] clusters per molecule which, by EPR spectroscopy, can be differentiated by their relaxation properties. The enzyme requires CoASH but not TPP for pyruvate oxidation activity and will not use 2-oxoglutarate, phenyl pyruvate or indole pyruvate as substrates. POR is virtually inactive at 25°C and shows a temperature optimum for pyruvate oxidation above 90°C. The apparent K m values for pyruvate, CoASH and P. furiosus ferredoxin at 80°C are 460, 100 and 70 μM, respectively. Carbon monoxide was a potent inhibitor of pyruvate oxidation (apparent K i = 7 μ M ). The half-life of activity ( t 50% ) in air at 25°C was 15 min and the t 50% value at 80μC (under anaerobic Conditions) was 23 min. Based on molecular comparisons with PORs from mesophilic organisms, it is proposed that P. furiosus POR may represent an ancestral form of a pyruvate-oxidizing enzyme.