cssi/SciSciGPT-SciSciNet huggingface dataset:
Beryllium: an etiologic agent in the induction of lung cancer, nonneoplastic respiratory disease, and heart disease among industrially exposed workers.

On the basis of the clear demonstration of the carcinogenicity of beryllium in several animal species along with the suggestion of an increased risk of lung cancer mortality in humans exposed to beryllium, an epidemiologic study of workers exposed to beryllium at one production facility was undertaken. Within the limitations imposed by the selection of data for calculation of cause-specific expected mortality (use of U.S. white male cause-specific mortality rates with linear extrapolation of 1965–1967 to 1968–1975 vs use of cause-specific mortality rates for the county in which the study facility and the majority of its workers resided), the study demonstrated a statistically significant increased risk of respiratory disease (neoplastic and nonneoplastic) and of heart disease mortality. A possible explanation other than in terms of beryllium was sought for this excessive risk of cause-specific mortality among beryllium-exposed workers. The excessive risk of lung cancer mortality could not be related to an effect of age, chance, self-selection, study group selection, exposure to other agents in the study facility, or place of residence. On the basis of the frequency of cigarette smoking among those cohort members employed in 1967–1968 and the distribution of histologic types of lung cancer among deceased cohort members, it seems unlikely that cigarette smoking per se could have accounted for the increased risk of lung cancer among beryllium-exposed workers in the study cohort. Lifetime employment histories for members of the study cohort were not available, so that definitive statements about the role of other occupational exposures cannot be made. However, information on usual occupations as indicated on death certificates suggests that it is unlikely that some undefined occupational or environmental exposure other than to beryllium could account per se for the excessive lung cancer mortality. This interpretation is further supported by the residential stability of the study cohort in a county having a lung cancer rate significantly lower than that of the entire United States. The findings of a statistically significant excess of lung cancer mortality among cohort members in general (P < 0.05) and among workers observed 25 or more years since onset of beryllium exposure in particular (P < 0.01), when taken in context with the results of earlier animal bioassay and recent epidemiologic studies, are supportive of the hypothesis that beryllium is carcinogenic to man.
Focal nodular hyperplasia and hepatic adenoma: a review of eight cases in the pediatric age group.

A review of all primary hepatic tumors seen at Children's Hospital, Boston over a 57-year period disclosed six cases of focal nodular hyperplasia (FNH) and two hepatic adenomas (HA). The children with FNH (four females, two males) ranged in age from 6 months to 15 years (average age: 7 years). Three patients had “hepatomegaly” noted on physical examination 2 months to 2 or more years prior to diagnosis. The average diameter of FNH was 7.3 cm (range 2.5-10 cm). The lesion was confined to the right lobe in four cases and showed bilobar involvement in two. The HA's were diagnosed in a newborn male and a 2-year-old girl, both of whom were symptomatic because of large tumor size (10 cm each). There was no maternal history of exposure to exogenous steroids during pregnancy. Three children with FNH underwent hepatic lobectomy and were alive and well 4 to 17 years later. One child who died of acute leukemia had an incidental FNH discovered at autopsy. Two patients were treated conservatively with biopsy only and were alive and symptom-free 13 and 15 years later. Both children with HA underwent hepatic lobectomy. One died postoperatively because of intra-abdominal hemorrhage and the other was alive and well 101A years later. Complete surgical resection is recommended for most children with HA when technically feasible because of 1) the lingering suspicion of possible (albeit remote) malignant transformation and 2) diagnostic difficulties in distnguishing HA from a well-differentiated hepatocellular carcinoma.
Explaining Variation in Organizational Identity Categorization

In explaining why constituent groups often vary in their perceptions of the most salient aspects of an organization’s identity, existing research has drawn, almost exclusively, on social identity research and self-enhancement motives. This research suggests that when different organizational identity categorizations are enhancing to some groups but not others, variation in organizational identity perceptions arises. In this paper, by contrast, we explore the role that unmotivated or “spontaneous” cognitions may play in influencing variation in constituents’ organizational identity categorizations. Based on data from a study of U.S. business school constituents, we develop a dual-path model through which both motivated and spontaneous processes influence the different organizational identity categorizations constituent groups find to be most salient. We discuss both the theoretical and practical implications of these findings.
Lupus Nephritis in African Americans

Lupus nephritis is more common and severe in African American women. Despite aggressive immunosuppressive therapies employed in lupus nephritis, African Americans have a higher incidence of progression to end-stage renal disease. The reasons for the racial disparities are not clear, but seem to be due to genetic, environmental, and socioeconomic factors. Hypertension and proteinuria are well-defined prognostic factors that significantly impact the course of renal disease progression for most forms of renal disease. However, clinical trials in lupus nephritis to date have not evaluated the role of aggressive antihypertensive or antiproteinuric therapies in retarding renal disease progression. Thus, additional studies are needed to better elucidate the natural history of lupus nephritis in African Americans and to optimize therapeutic strategies for those who are identified as being at high risk.
TU-E-108-01: Comparison of Two Methods for Daily Dose Reconstruction of Volumetric Modulated Arc Therapy Treatments

Purpose: To compare daily dose reconstruction of volumetric modulated arc therapy treatments using delivery log files from two sources: the treatment control system (TCS) and the record and verify (RV) system. The former has the advantage of automated operation from remote terminals while the latter has the advantage of better recording fidelity. Methods: VMAT treatment plans from five prostate patients and five head and neck patients treated at our clinic were selected for this study. Each plan was delivered on an Elekta linear accelerator, and the resulting dose distribution was measured with a two‐dimensional diode array. During delivery, positions of the gantry, multi‐leaf collimator (MLC), and jaws were captured in the RV system and in the TCS through third party software. Following plan delivery, delivery parameters were imported to the treatment planning system and used to recalculate the dose delivered to the measurement phantom. Planar dose profiles were computed for the planned and reconstructed (RV and TCS) doses. Each of the planar doses were compared to the measured dose using the gamma metric with 3% dose difference and 3 mm distance to agreement. Results: The average improvement over the agreement between the planned and measured doses was 0.2% ± 0.8% and 0.7% ± 0.6% for RV‐and TCS‐reconstructed doses for prostate cases, respectively; and −;0.6% ± 0.7% and 0.3 ± 0.6% for head and neck cases, respectively. In other words, TCS‐reconstruction improved agreement for both treatment sites while RV‐reconstruction showed only slight improvement in prostate cases. Conclusion: Dose reconstructed with TCS log files more closely reflects the delivered dose than does the original plan. Reconstruction with RV data shows similar potential, but time delays in the reporting of different parameters diminish its ability for plans requiring greater MLC movements.
Spherical lamina emergent mechanisms

Abstract Lamina emergent mechanisms (LEMs) are compliant mechanisms that can be manufactured from planar materials and are capable of motion out of the plane of manufacture. Spherical LEMs combine the unique motion of spherical mechanisms with the compactness and simple topology of LEMs. The fundamentals of spherical LEMs are discussed in this work. It is found that 21 of the 33 possible spherical 4R types can be spherical LEMs. A classification based on these 21 possible types is developed. This classification is used to predict motion capabilities of spherical 6R mechanisms. It is also applied to arrays of spherical mechanisms. The extreme compactness and sophisticated motion of spherical LEMs makes them candidates for application that are weight and volume sensitive and may find use in future surface morphing applications.
1025 CONCANAVALIN A BINDING PROTEINS OF THE HUMAN POLYMORPHONUCLEAR LEUKOCYTE PLASMA MEMBRANE

1025 CONCANAVALIN A BINDING PROTEINS OF THE HUMAN POLYMORPHONUCLEAR LEUKOCYTE PLASMA MEMBRANE
Neither Just nor Necessary: Barth and War, Again

The terms "justice" and "necessity" are often employed in discussions of war. The just war tradition seeks to delineate when wars are and are not just; other theologians who do not find this approach helpful may nevertheless resort to the logic of necessity. Although unjust, some wars may still be deemed necessary. Barth employs both the language and logic of justice and necessity in his approach to war. The purpose of this paper is to address Barth's exposition of war in relation to his approach to divine justice and the necessity of Christian affliction. It does not attempt to make any large claims about the just war tradition or other approaches to war. Rather, it is intended to be an immanent critique of Barth from Barth's own theology, showing that, although consistent with his view of church and state, Barth's theology of war is inconsistent with his view of both God's character as just and the external necessity of affliction to Christian witness.
How do writers view usability information? A case study of a developing documentation writer

As Dieli (1989) notes, writers sometimes have trouble focusing their concerns into questions that usability groups can test. As teachers of future documentation writers, we have observed that writers also have trouble turning the results of those usability tests into strategies for document revision. Our first investigation into these issues—see Sullivan & Porter (1990)—described a class of fifteen professional writing students employing usability information to write computer documentation. That study indicated that the writer's use of information is guided by that writer's rhetorical orientation, particularly his/her view of the audience/user. Though all the writers in the study conducted the same type of usability test (modeled after Atlas' “user edit”—see Atlas, 1981), they interpreted their test results in different ways.This investigation continues the Sullivan & Porter (1990) study using a longitudinal case study of one professional writer, called “Max.” This follow-up study aims to probe how the writer's rhetorical orientation guides that writer's interpretation of usability test results.We take a slightly uncommon view of usability. We have opted to focus on the writer's view of users' actions—both what is noticed and how it is interpreted. Typically, usability studies have examined the interaction between texts/systems and readers/users (see McDonald & Schvaneveldt, 1988; Ramey, 1988; Rubens & Rubens, 1988), subordinating the important variable of how the writer interprets and uses results. Although both Sullivan (March, 1985) and Schriver (1987) suggest that writers can be trained to successfully use user information in revising documents they do not author, usability studies still have not examined how writers view the findings from usability studies run on their own work.Our study examines how, and to what degree, one writer's rhetorical orientation filters results from usability tests. what is his rhetorical orientation?what value does he place on, and how does he classify and apply, usability test information?
Molecular dynamics simulations of ice growth from supercooled water

The kinetics of ice growth on the secondary prismatic plane and the basal plane {0001} is studied by Molecular Dynamics simulations. The simulation system initially consists of a slab of ice in contact with a layer of water on one side, and vacuum on the other side. The remaining surface of the water layer is also facing vacuum. The time evolution of the system shows the crystallization of the liquid water and the evaporation of very few molecules at the free surfaces. The ice vapour interfaces are wet on both sides by identical thin layers of liquid water, strongly suggesting that the system has reached its equilibrium state. To analyse the results, we have developed a new method to discriminate whether a molecule belongs to the ice lattice or is in liquid state. Using this method to monitor the number of ice molecules as a function of time, we find that the freezing is much faster on the prismatic plane than on the basal plane. For the prismatic plane, irregularities in the surface of the solid phase ar...
Information and effort in contingent valuation surveys: application to global climate change using national internet samples ☆

This contingent valuation study investigates the issues of information access and respondent effort, and is based on a series of national Internet samples. The focus is on a split-sample treatment, Basic Information (BI) versus Enhanced Information (EI). In the latter, significantly expanded information is provided about global climate change and the Kyoto Protocol. Using a referendum format, we compare the treatment effect (BI versus EI) on willingness to pay (WTP). We develop measures of respondent effort in accessing optional information, through the technology of Web-based surveys, and jointly model effort and WTP using a simultaneous estimation approach. Results support the use of the joint modeling approach for objective measures of respondent effort and WTP. Respondent effort is shown to be positively and significantly related to WTP. However, use of the optional menu is rather modest (counts of pages and time spent), and is highly variable (both across pages and respondents).
Surgical Stabilization of Flail Chest: The Impact on Postoperative Pulmonary Function

Objectives Flail chest results in significant morbidity. Controversies continue regarding the optimal management of flail chest. No clear guidelines exist for surgical stabilization. Our aim was to examine the association of bedside spirometry values with operative stabilization of flail chest.
Breast reconstruction with gluteal artery perforator flaps

Summary Background Several alternatives exist for breast cancer reconstruction with perforator flaps. For those patients in whom the buttock is the best choice as a source for autologous tissue, the IGAP and SGAP flaps are an excellent option. These flaps allow the reliable transfer of skin and soft tissue from the buttock without the associated donor site morbidity of a muscle flap. Indications Most women requiring tissue transfer to the chest from the buttock for breast reconstruction or other reasons are candidates for IGAP or SGAP flaps. Do to an improved donor site contour and scar, we now prefer to use the IGAP to the SGAP flap. Absolute contraindications specific to perforator flap breast reconstruction in our practice include history of previous liposuction of the donor site or active smoking (within 1 month prior to surgery). Anatomy and technique IGAP and SGAP flaps are based on perforators from either the superior or inferior gluteal artery. These perforators are carefully dissected free from the surrounding gluteus maximus muscle, which is spread in the direction of the muscle fibres and safely preserved. The vascular pedicle is anastomosed to recipient vessels in the chest and the donor site closed primarily. Conclusions IGAP and SGAP flaps allow the safe and reliable transfer of tissue from the buttock for breast reconstruction as an alternative to soft tissue transfer from an abdominal donor site or even as a first choice in selected patients.
Bifurcation Analysis of Hopping Behavior in Cellular Pattern-Forming Systems

We use symmetry-based arguments to derive normal form equations for studying the temporal behavior of a particular spatio-temporal dynamic cellular pattern, called "hopping" state, which we have recently discovered in computer simulations of a generic example of an extended, deterministic, pattern-forming system in a circular domain. Hopping states are characterized by cellular structures that sequentially make abrupt changes in their angular positions while they rotate, collectively, about the center of the circular domain. A mode decomposition analysis suggests that these patterns are created from the interaction of three steady-state modes. A bifurcation analysis of associated normal form equations, which govern the time-evolution of the steady-state modes, helps us quantify the complexity of hopping patterns. Conditions for their existence and their stability are also derived from the bifurcation analysis. The overall ideas and methods are generic, so they can be readily applied to study other type of spatio-temporal pattern-forming dynamical systems with similar symmetry properties.
Average stress in the matrix and effective moduli of randomly oriented composites

Abstract By considering the variation of average stress in the matrix, some elastic properties of randomly oriented composites are established as a function of aspect ratio. Both three- and two-dimensional random orientations, resulting, respectively, in a complete and transverse isotropy, are considered. As the shape of inclusions changes, the isotropic bulk and shear moduli are shown to vary within the Hashin-Shtrikman bounds. The aspect ratio dependence of the five in-plane and out-of-plane moduli with planar orientations are also explicitly given; these results suggest that the in-plane properties are most effectively reinforced by fibrous inclusions, whereas the out-of-plane ones are more responsive to the disc type. The accompanying variations of average stress in the matrix are seen to be closely related to the corresponding variations of the moduli. Comparisons with some limited experimental data also show a reasonable agreement.
Cross Correlation by Neurons of the Medial Superior Olive: a Reexamination

Initial analysis of interaural temporal disparities (ITDs), a cue for sound localization, occurs in the superior olivary complex. The medial superior olive (MSO) receives excitatory input from the left and right cochlear nuclei. Its neurons are believed to be coincidence detectors, discharging when input arrives simultaneously from the two sides. Many current psychophysical models assume a strict version of coincidence, in which neurons of the MSO cross correlate their left and right inputs. However, there have been few tests of this assumption. Here we examine data derived from two earlier studies of the MSO and compare the responses to the output of a computational model. We find that the MSO is not an ideal cross correlator. Ideal cross correlation implies a strict relationship between the precision of phase-locking of the inputs and the range of ITDs to which a neuron responds. This relationship does not appear to be met. Instead, the modeling implies that a neuron responds over a wider range of ITDs than expected from the inferred precision of phase-locking of the inputs. The responses are more consistent with a scheme in which the neuron can also be activated by the input from one side alone. Such activation degrades the tuning of neurons in the MSO to ITDs.
Dynamics and thermodynamics of a nonlinear model for DNA denaturation.

We present a model for the dynamical structure of DNA that can be considered as an extension of the usual Ising-like statistical approach to the melting curves. The model uses the stretching of the hydrogen bonds in a base pair as its main variable. Numerical simulations at constrained temperature show that it provides a good qualitative description of the collective motions of the base pairs, including their large-amplitude fluctuational openings and the emergence of the denaturation bubbles from the thermal fluctuations. The results are in good agreement with a statistical-mechanics analysis of the denaturation and specific-heat curves, performed with the transfer-integral method, provided that discreteness effects are treated exactly by a numerical solution of the transfer-integral operator. Second-order self-consistent phonon theory agrees with the exact transfer-integral results in the low- and intermediate-temperature ranges and explains the phonon softening observed in the molecular-dynamics simulations. When the temperature approaches the denaturation temperature, the second-order self-consistent phonon results deviate significantly from the exact ones, pointing to the fundamental role of nonlinear processes in DNA denaturation.
Conformation and restricted segmental flexibility of C1, the first component of human complement

Seventy selected images of chemically crosslinked C1 are analyzed to illustrate structural details of the C1qC1r2C1s2 complex. From inspection of these images, the C1r2C1s2 tetramer can be seen to be located in the region of the C1q arms, cleanly separated from the C1q heads and from at least 90%, if not all, of the C1q stem. From measurements made upon 65 images, the semicone angles formed between the spreading arms and the symmetry axis passing through the stem of C1 may be calculated. Unlike C1q, for which a wide variety of angles is found, the C1 complex appears to possess a restricted range of angular flexibility with an average value of about 50 degrees. The volume inside the cone formed by the spreading arms of C1q is too small to contain the entire C1r2C1s2 tetramer; at least some of the tetramer must lie outside the cone when it is bound to C1q to form C1. From our knowledge of the sizes and structures of its subunits, and from symmetry considerations, a model is proposed for the configuration of the C1 complex in which the middle portion of the C1r2C1s2 tetramer is centrally located among the arms close to the stem of the C1q and with the two protruding ends of the tetramer wrapped around the outside of the cone. Functional implications of this more rigid structure are discussed with relevance to C1q-induced aggregation of latex beads and C1-induced disaggregation.
Mapping speed for an array of corrugated horns

I address the choice of horn diameter for millimeter-wave array receivers with corrugated horns. For maximum point-source mapping speed, in both total power and polarization with typical receiver noise contributions and a close-packed horn array that fills the field of view, the optimum horn diameter is 1.6-1.7Fλ, where F is the focal ratio. A ±25% change in horn diameter gives <10% degradation in mapping speed. Correlated noise from the cold stop, atmosphere, and cosmic microwave background has little effect on the mapping speed and optimum horn diameter.
The use of vestibular models for design and evaluation of flight simulator motion

Quantitative models for the dynamics of the human vestibular system are applied to the design and evaluation of flight simulator platform motion. An optimal simulator motion control algorithm is generated to minimize the vector difference between perceived spatial orientation estimated in flight and in simulation. The motion controller has been implemented on the Vertical Motion Simulator at NASA Ames Research Center and evaluated experimentally through measurement of pilot performance and subjective rating during VTOL aircraft simulation. In general, pilot performance in a longitudinal tracking task (formation flight) did not appear to be sensitive to variations in platform motion condition as long as motion was present. However, pilot assessment of motion fidelity by means of a rating scale designed for this purpose, were sensitive to motion controller design. Platform motion generated with the optimal motion controller was found to be generally equivalent to that generated by conventional linear crossfeed washout. The vestibular models are used to evaluate the motion fidelity of transport category aircraft (Boeing 727) simulation in a pilot performance and simulator acceptability study at the Man-Vehicle Systems Research Facility at NASA Ames Research Center. Eighteen airline pilots, currently flying B-727, were given a series of flight scenarios in the simulator under various conditions of simulator motion. The scenarios were chosen to reflect the flight maneuvers that these pilots might expect to be given during a routine pilot proficiency check. Pilot performance and subjective rating of simulator fidelity was relatively insensitive to the motion condition, despite large differences in the amplitude of motion provided. This lack of sensitivity may be explained by means of the vestibular models, which predict little difference in the modeled motion sensations of the pilots when different motion conditions are imposed.
Frequency domain analysis of marine risers with time dependent tension

A model of a marine riser system which is appropriate for the study of its dynamic behavior in deep water conditions is developed. This model is used to estimate the steady-state riser response to harmonic excitation. In this regard the finite element method yields a linear discrete multidegree-of-freedom structural model. The resulting stiffness matrix is time dependent due to fluctuations in the riser top tension. Further, Morison's equation is used for estimating the hydrodynamic load on the riser. Due to the nonlinearity of the drag term appearing in this equation, the equation of motion of the riser is nonlinear. An approximate analysis procedure based on the concepts of equivalent linearization and time averaging leads to efficient determination of the riser maximum stress. A continuous beam model under a constant tension equal to the average of the top and bottom riser tensions is used to provide an alterate estimate of its natural frequencies. Numerical results from a variety of parametric studies are reported. The computational features of the proposed method make it quite appropriate for implementation on personal computers which can be used in the preliminary design stage of marine risers.
Experimental down-regulation of intermediate biomarkers of carcinogenesis in mouse mammary epithelial cells

The polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)anthracene (DMBA) is a metabolism-dependent procarcinogen whose tumorigenicity is modified by dietary and endocrine manipulationsin vivo. DMBA initiates molecular and cellular alterations in the mammary tissue, while dietary components and estrogens affect the post-initiational phase of tumorigenic transformation. The mechanism(s) responsible for modulation of tumorigenic transformation remain unclear. This study examines the effects of selected tumor suppressing agents and estradiol (E2) metabolites onin vitro DMBA carcinogenesis utilizing a newly established mouse mammary epithelial cell line C57/MG. Alteration in DNA repair synthesis, metabolism of E2 via the C2- and C16α-hydroxylation pathways, and acquisition of anchorage-independent growth were utilized as molecular, endocrine, and cellular biomarkers to quantitate the cellular transformation by DMBA and its modulation by tumor suppressing agents and E2 metabolites. A single 24 hr exposure of 0.78 µM DMBA to C57/MG cells resulted in a 193.9% increase in DNA repair synthesis and a 73.1% decrease in C2/C16α hydroxylation of E2. The DMBA treated C57/MG cells also exhibited increased anchorage-independencein vitro prior to tumorigenesisin vivo. A simultaneous treatment of cells with DMBA and with the highest non-cytotoxic doses of the tumor suppressing agents 5 µM N-(4-hydroxyphenyl) retinamide (HPR), 50 µM indole-3-carbinol (I3C), or 1 µM tamoxifen (TAM) resulted in a 35.6% to 63.9% decrease in DNA repair synthesis, a 23.8% to 1347.6% increase in C2/C16α hydroxylation of E2, and a 53.8% to 72.4% decrease in anchorage-independent growth. The E2 metabolites at the highest non-cytotoxic doses of 0.76 µM estrone (E1), 0.69 µM 2-hydroxyestrone (2-OHE1), and 0.66 µM 2-methoxyestrone (2-MeOHE1) suppressed DMBA-induced DNA repair synthesis by 56.0% to 68.8%. These tumor suppressing agents and E2 metabolites also effectively suppressed post-initiational, anchorage-independent growth by 24.9% to 72.4%. These results indicate that DMBA induces cellular transformation in part by causing DNA damage, altering C2/C16α hydroxylation in favor of C16α-hydroxylation, and inducing anchorage-independent growth prior to tumor development. Effective downregulation of these genotoxic, endocrine and proliferative end points by prototypic tumor suppressing agents and by E2 metabolites generated via the C2-hydroxylation pathway suggest that these agents may influence mammary tumorigenesis by inhibiting early occurring initiational and/or post initiational events.
Formalization of workflows for extracting bridge surveying goals from laser-scanned data

Abstract Laser scanners enable bridge inspectors to collect dense 3D point clouds, which capture detailed geometries of bridges. While these data sets contain rich geometric information, they bring unique challenges related to geometric information retrieval. This paper describes a case study to show the necessity and potential value of automating the manual data processing workflows being executed for extracting geometric data items (surveying goals) from 3D point clouds, and presents an approach for formalizing these workflows to enable such automation. We analyzed manual procedures of taking measurements on 3D point clouds and as-built models for obtaining bridge inspection related surveying goals, synthesized and categorized all data processing operations into nine generic operations. These nine categories of operations can be formalized using tuples. Using these tuples, we formalized an operation library and workflow construction mechanisms for enabling inspectors to semi-automatically construct executable workflows. This formalism also incorporates several mechanisms for facilitating extensions to the existing operation library to accommodate additional surveying goals that have not been covered. The developed approach is validated for its generality to support workflows needed for all surveying goals required by the National Bridge Inventory (NBI) program, and for its extensibility to support workflows needed to support a variety of other surveying goals identified in the Architecture/Engineering/Construction domain.
α-Amino-3-hydroxy-5-methyl-4-isoxazole Propionate Receptor Subunit Composition and cAMP-response Element-binding Protein Regulate Oligodendrocyte Excitotoxicity

Developing oligodendrocytes (OLs) are highly vulnerable to glutamate excitotoxicity. Although OL excitotoxicity is mainly mediated by α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors (AMPARs) and is Ca2+-dependent, the molecular basis for AMPAR-mediated Ca2+ influx in OLs remains largely unclear. Ca2+ permeability of AMPARs is inversely correlated with the abundance of the AMPAR subunit glutamate receptor 2 (GluR2). Here we report that GluR2-containing and GluR2-lacking AMPARs are co-expressed in individual OLs and that a subset of AMPARs on each OL are Ca2+-permeable and mediate OL excitotoxicity. Virus-mediated overexpression of GluR2 reduces OL excitotoxicity, whereas expression of its unedited form GluR2(Q) enhances the excitotoxicity. These findings indicate that GluR2 critically controls OL excitotoxicity. During OL excitotoxicity, the transcriptional factor cAMP-response element-binding protein (CREB) is transiently phosphorylated and subsequently down-regulated. Virus-mediated expression of a constitutively active form of CREB, both in cultured OLs in vitro and in developing cerebral white matter in vivo, up-regulates GluR2, inhibits Ca2+ permeability, and protects OLs from excitotoxicity. Overall, these data suggest that targeting GluR2-lacking AMPARs or CREB may be a useful strategy for treating nervous system disorders associated with OL excitotoxicity.
Image-guided intervention in the human bile duct using scanning fiber endoscope system

Bile duct cancers are increasing in frequency while being difficult to diagnose. Currently available endoscopic imaging devices used in the biliary tree are low resolution with poor image quality, leading to inadequate evaluation of indeterminate biliary strictures. However, a new ultrathin and flexible cholangioscope system has been successfully demonstrated in a human subject. This mini-cholangioscope system uses a scanning fiber endoscope (SFE) as a forward-imaging guidewire, dimensions of 1.2-mm diameter and 3-m length. Full color video (500-line resolution at 30Hz) is the standard SFE imaging mode using spiral scanning of red, green, and blue laser light at low power. Image-guided operation of the biopsy forceps was demonstrated in healthy human bile ducts with and without saline flushing. The laser-based video imaging can be switched to various modes to enhance tissue markers of disease, such as widefield fluorescence and enhanced spectral imaging. In parallel work, biochemical discrimination of tissue health in pig bile duct has been accomplished using fiberoptic delivery of pulsed UV illumination and time-resolved autofluorescence spectroscopic measurements. Implementation of time-resolved fluorescence spectroscopy for biochemical assessment of the bile duct wall is being done through a secondary endoscopic channel. Preliminary results indicate that adequate SNR levels (> 30 dB) can be achieved through a 50 micron fiber, which could serve as an optical biopsy probe. The SFE is an ideal mini-cholangioscope for integration of both tissue and molecular specific image contrast in the future. This will provide the physician with unprecedented abilities to target biopsy locations and perform endoscopically-guided therapies.
The electrocardiogram and vectorcardiogram of the normal infant.

SUMMARY 1.Electrocardiograms and vectorcardiograms (both the cube and tetrahedron frames of reference) were recorded on 300 infants one to 30 days of age. These infants were restudied at intervals of one to three months during the first year and every six months thereafter. Many have now reached the age of two and one-half years. 2.Considerable variation was found in the electrocardiogram among individuals. Most commonly there was a gradual change in direction of the mean QRS axis toward the left during infancy, but right axis deviation (110° to 120°) sometimes persisted throughout infancy. The development of left axis deviation after three months of age was not rare. The large R wave in Leads V4r and V1 may remain throughout infancy, but more commonly, gradually become smaller. Notching of the R wave in these leads were not seen in newborns but was not infrequent later. Small Q waves in these leads were not rare. Extremely high voltage may be seen in the chest leads, especially V2 and V4. 3.Correlation exists between the standard electrocardiogram and vectorcardiogram. The frontal plane QRS loop of the tetrahedron contains virtually identical information as the standard Einthoven leads; the horizontal plane loop of this system was found to be valueless. The horizontal loop of the cube usually was inscribed clockwise in newborns, later it became a figure-of-eight, and finally an open loop inscribed in a counter-clockwise manner. Great individual variation was encountered: a counterclockwise loop may be seen in newborns and a clockwise loop in two year olds. The horizontal loop of the cube system could be predicted from the standard electrocardiogram fairly accurately. 4.The T waves of the limb leads do not differ among individuals as much as the QRS complexes nor do characteristic serial changes occur. During the first few days of life the T wave in Leads V4r and V1 is not infrequently upright, but this is uncommon at one month and was not seen by three months of age. 5.A theoretical analysis of the QRS loop of the infant, based on anatomical and physiological data, is presented. Theoretically the horizontal projection of the QRS loop would not be expected to be inscribed in a clockwise manner unless the right ventricle was thicker than the left. Since this is not true even during the first few months of life, it is believed that a distortion inherent in the cube system of vectorcardiography exaggerates the right ventricular effects to produce the clockwise inscribed loops seen in records made with this method.
Aluminum powder metallurgy processing

The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.
Research issues in active database systems: report from the closing panel at RIDE-ADS '94

The discussions during the panel stayed largely but not entirely focused on the question of active database research issues from the application perspective. There were nine panelists. Each panelist was asked to prepare brief answers to a set of questions. The sets of answers were discussed by all participants, and finally a number of more general issues were discussed.The questions asked of the panelists were: Name an application that will certainly be supported by active database systems in the not-too-distant future.Name an application that will certainly not be supported by active database systems in the near future.Name an area of active database systems in which you are not working but that is crucial to meet the needs of applications.Name an area of active database systems that is not on the critical path to supporting applications.Name an area of active database systems that should have been discussed in the course of the workshop but was not.
Unsupportive Social Interactions in the Weeks Immediately Following Breast Cancer Diagnosis

Unsupportive social interactions (USIs) experienced by people with cancer negatively affect psychological well-being. Forty-five interviews with 26 women were analyzed using directed content analysis to explore USIs experienced during the stressful pretreatment and early postsurgical periods after early-stage breast cancer diagnosis. Cognitive, emotional, and behavioral responses to USIs were also explored. Seventy incidents of USIs were identified within the interviews and grouped into four previously defined and five additional categories. Anxiety, avoiding future interactions, and nondisclosure of thoughts and feelings were typical responses to USIs. These responses hold implications for women's psychological well-being and need for future interventions and research.
Dual-polymer electrochromic film characterization using bipotentiostatic control

We report an analytical method which allows the systematic variation of color states of pairs of electrochromic conjugated conducting polymers with simultaneous spectroelectrochemical and colorimetric characterization of the resulting color summation. This method measures colors by transmitting light through two polymer films stacked together in electrolyte and under separate potentiostatic control. The polymers that were used in this work are poly(3,4-ethylenedioxythiophene) (PEDOT), poly(3,4-propylenedioxypyrrole) (PProDOP), and dihexyl-substituted poly(3,4-propylenedioxythiophene) (PProDOT-Hx2). These are all cathodically coloring polymers, PEDOT switching from a transmissive sky blue to a deep blue, PProDOP switching from a highly transmissive gray/blue to a brown and then to an orange, and PProDOT-Hx2 switching from a transmissive sky blue to a purple/magenta color upon reduction. Coupling these polymers logically by the dual-polymer electrochromic film characterization technique led us to obtain new...
Observations of PKKP Precursors Used to Estimate Small-Scale Topography on the Core-Mantle Boundary

Stacks of global seismic data reveal the time and distance dependence of high-frequency (1-hertz) precursors to the seismic phasePKKP. Synthetic seismogram modeling shows that scattering from random small-scale topography at the PKKPcore-mantle–boundary reflection point generates precursory arrivals similar to those seen in the data. Models with a root mean square core-mantle–boundary topography of 250 to 350 meters and correlation length of 7 to 10 kilometers explain the main features of the data. However, a systematic range-dependent misfit between observed and predicted precursor power suggests that inner core scattering may contribute to the precursors.
Clinical development of a failure detection-based online repositioning strategy for prostate IMRT—Experiments, simulation, and dosimetry study

Purpose: To implement and evaluate clinic-ready adaptive imaging protocols for online patient repositioning (motion tracking) during prostate IMRT using treatment beam imaging supplemented by minimal, as-needed use of on-board kV. Methods: The authors examine the two-step decision-making strategy: (1) Use cine-MV imaging and online-updated characterization of prostate motion to detect target motion that is potentially beyond a predefined threshold and (2) use paired MV-kV 3D localization to determine overthreshold displacement and, if needed, reposition the patient. Two levels of clinical implementation were evaluated: (1) Field-by-field based motion correction for present-day linacs and (2) instantaneous repositioning for new-generation linacs with capabilities of simultaneous MV-kV imaging and remote automatic couch control during treatment delivery. Experiments were performed on a Varian Trilogy linac in clinical mode using a 4D motion phantom programed with prostate motion trajectories taken from patient data. Dosimetric impact was examined using a 2D ion chamber array. Simulations were done for 536 trajectories from 17 patients. Results: Despite the loss of marker detection efficiency caused by the MLC leaves sometimes obscuring the field at the marker’s projected position on the MV imager, the field-by-field correction halved (from 23% to 10%) the mean percentage of time that target displacement exceeded a 3 mm threshold, as compared to no intervention. This was achieved at minimal cost in additional imaging (average of one MV-kV pair per two to three treatment fractions) and with a very small number of repositionings (once every four to five fractions). Also with low kV usage ( ∼ 2 / fraction ) , the instantaneous repositioning approach reduced overthreshold time by more than 75% (23% to 5%) even with severe MLC blockage as often encountered in current IMRT and could reduce the overthreshold time tenfold (to 2 % ) if the MLC blockage problem were relieved. The information acquired for repositioning using combined MV-kV images was found to have submillimeter accuracy. Conclusions: This work demonstrated with a current clinical setup that substantial reduction of adverse targeting effects of intrafraction prostate motion can be realized. The proposed adaptive imaging strategy incurs minimal imagingdose to the patient as compared to other stereoscopic imaging techniques.
The relative rates of the boudouard reaction and hydrogenation of CO over Fe and Co foils

Abstract The purpose of this investigation was to determine the primary reaction responsible for carbon deposition when Fe and Co foils were exposed to a five-gas mixture of H2, CO, CH4, CO2, and H2O at 900 K and 1 atm. Binary (CO-CO2, and CH4-H2) gas mixtures were used to study the relative rates of carbon deposition; however, the role of H2 as a facilitator with CO-CO2 gas mixtures is left unanswered. A ternary gas mixture of H2-CO-H2O can be used to investigate the role of H2; however, this gas mixture results in an infinite a c for carbon deposition via the Boudouard reaction. In order to simultaneously control the gas-phase carbon activity of both the Boudouard reaction and the hydrogenation of CO, it is necessary to use a four-gas mixture of H2, CO, CO2, and H2O. Reactions were carried out over Fe and Co foils at 900 K and 1 atm. The rate of carbon deposition was determined as a function of gas phase carbon activity ( a c ) of the Boudouard reaction and the hydrogenation of CO. By carefully choosing different four-gas mixtures, it is possible to simultaneously adjust the a c of each reaction such that the a c of CO hydrogenation is increasing, while the activity to form carbon deposits via the Boudouard reaction is decreasing, and vice versa. In this manner, the relative driving force for carbon deposition from each reaction can be controlled with H2 still present in the gas mixture, thus eliminating the question as to whether H2 enhances the Boudouard reaction. Results indicate that the hydrogenation of CO is the main reaction for carbon deposition at 900 K and 1 atm. Also, CO hydrogenation appears to govern carbide formation.
FORMATION OF EPITAXIAL (001) ORDERED FePd FILMS FROM MULTILAYER PRECURSORS

Epitaxial, (001) oriented Fe/Pd multilayers were deposited by DC magnetron sputtering onto single crystal (001) MgO. Annealing resulted in the formation of c-axis oriented ordered intermetallic compounds with the tetragonal L1o crystal structure and the orientation relationship (001)FePd || (001)MgO and [110]FePd || [110]MgO. Accompanying the formation of this phase was a switch from an in-plane to an out-of-plane magnetic easy axis with a perpendicular magnetic anisotropy of 6x106 erg/cm3. The magneto-optic Kerr rotation of ordered FePd is maximum near 1.6 eV and minimum near 2.9 eV, with values of 0.29 and 0.05°, respectively.