cssi/SciSciGPT-SciSciNet huggingface dataset:
One-step fabrication of three-dimensional polydimethylsiloxane peel-off microwell array for cell trapping

A three-dimensional polydimethylsiloxane (PDMS)-based microarray was one-step fabricated by releasing from an SU-8 mold for cell trapping. A human embryonic kidney-293 cell line was cultured on the PDMS microarray. By taking advantage of the chemical nature difference between PDMS surface released from oxidized silicon and released from SU-8 substrate, cells can only grow and be attached inside the PDMS microarray after 2 days of cell culture. To investigate the substantial nature of the cell adhesion and repellency on the PDMS substrate, atomic force microscopy, contact angle, and x-ray photoelectron spectroscopy methods have been carried out to analyze the physical and chemical properties of the PDMS material surfaces under different surface treatment circumstances.
Toward Simple Learning Design 2.0

In 2003, based on the work done by the OUNL on Educational Modeling Language, IMS-LD was released and brought to the research community a new era in the design of learning activities. Six years later, IMS-LD is no longer evolving while facing an increasing number of critiques. The specification is still not implemented by any leading brands in the e-learning industry. The current development of new IMS specifications offers a window of opportunity to rethink IMS-LD. After discussing IMS-LD, trying to understand the existing critiques and analyzing the new technical context, this paper proposes the guidelines for the creation of this new learning design specification. This specification would be split in two specifications satisfying both the instructional designers and the learning platform developers and vendors. The specification optimized to learning platform vendors, called Simple Learning Design 2.0 will be designed to ease the deployment of the learning design concepts in the existing Learning Management Systems. SLD 2.0 is currently developed in the context of the SynergiC3 project.
Extraction of Hydrophobic Species into a Water-Soluble Synthetic Receptor

A deep, water-soluble cavitand extracts a variety of neutral hydrophobic species into its cavity. Flexible species such as n-alkanes tumble rapidly on the NMR time scale inside the cavity, but this motion is slowed for bulkier guests. Long, rigid guests such as p-substituted aromatics are either static or only tumble at elevated temperatures via flexing motions of the cavitand. Strong selectivity in recognition of long rigid guests is seen. The binding of neutral guests occurs via the classical hydrophobic effect; the process is entropically favored, as shown by isothermal titration calorimetry measurements. Binding affinities are generally on the order of 104−105 M-1. The extent of the hydrophobic stabilization is shown by the binding of long trimethylammonium salts, which bind the alkyl chain in the cavity, rather than the NMe3+ group. Dynamic NMR studies show that self-exchange of neutral guests is independent of guest concentration, and most likely occurs via rate-determining unfolding of the cavitand...
Polarized extinction properties of plates with large aspect ratios

Abstract The extinction matrices for both infinite-radius plates and finite-size particles are derived by assuming the far-field scattered waves to be either plane waves or spherical waves, and the connection between the two formalisms is discussed. In both cases, the elements of the extinction matrix are compared numerically for various incident angles and size parameters. Agreement is found between the results for the infinite-radius plates and plates with large aspect ratios and small incident angles. The differences between the two treatments provide insight into the understanding of the extinction properties of non-spherical particles illuminated by polarized incident light.
Chromosomal abnormalities in indolent lymphoma

Cytogenetic studies were performed on lymph node biopsies from 60 patients with indolent (low grade) non-Hodgkin's lymphoma. Thirty-two of the 39 successfully cultured biopsies had abnormal clones. The 32 abnormal clones represented the following histologies: seven small lymphocytic lymphoma (SL), eight follicular small cleaved cell lymphoma (FSC), 14 follicular mixed, small cleaved, and large cell lymphoma (FM), and three composite lymphomas. One of the composite lymphomas had FSC/DSC (diffuse small cleaved cell) and the other two FM/DM (diffuse mixed, small cleaved and large cell). Twenty-seven of the 32 biopsies were immunologically typed, and all were B cell. The clones all exhibited more structural than numerical abnormalities, and there was no difference in the modal chromosome number of the abnormal clones found in each histology. Biopsies with no normal cells were more frequently found in the SL histology (71%) than in the two follicular lymphoma groups (54%-55%). A translocation of the 14q32 segment was the most common abnormality found in all three histologies. In the follicular lymphomas a t(14;18)(q32;q21) was seen in 52% (13 of 25) of these patients, this translocation was not observed in the SL patients. Overall 84% (21 of 25) of the follicular lymphoma patients had abnormalities of 14q32 and/or 18q21. Other specific abnormalities included anomalies of chromosome #3 in FM, an abnormal 10q in FSC and FM lymphoma, and a high incidence of +18 and chromosome #1 abnormalities in patients with t(14;18). The presence of specific chromosome abnormalities in the indolent lymphoma patients suggests a relationship between certain karyotypic features and histology.
Involvement of nitric oxide in the deregulation of cytosolic calcium in cerebellar neurons during combined glucose-oxygen deprivation

Nitric oxide (NO) has been proposed as a neuronal messenger molecule in hypoxic/ischemic cell injury (Nowicki et al., 1991; Trifiletti, 1992). We conducted studies in a model of combined glucose-oxygen deprivation using cultured rat cerebellar granule cells. Experiments were designed to test the hypothesis that sustained elevation of cytosolic calcium ([Ca2+]i) and NO generation act in concert to trigger neuronal injury after anoxic insult. A hypoxic state was achieved by perfusing the cells with medium pre-equilibrated with argon gas. [Ca2+]i was monitored using digital-imaging fluorescence microscopy in cells loaded with fura-2 AM. Under short-term hypoxic conditions, cells displayed a progressive and sustained, moderate increase of [Ca2+]i, which returned to near basal levels on restoration of O2-containing medium. Prolonged hypoxic conditions (>60 min) caused irreversible elevation of [Ca2+]i followed by disruption of cell membrane integrity, as indicated by severe swelling, loss of regular cell shape and processes, leakage of dye fura-2, and propidium iodide uptake (“point of no return”). Pretreatment withNG-nitro-l-arginine methyl ester (l-NAME, 100 μM), a specific NO synthase inhibitor, markedly delayed the onset of intensity of the rise of [Ca2+]i. The hypoxia-induced elevation of [Ca2+]i was also greatly attenuated ifl-NAME (100 μM) was added to the argon-perfused medium before the cells demonstrated signs of irreversible injury. Prolonged or repeated hypoxic conditions, however, caused a rapid and intense increase of [Ca2+]i, which could not be blocked by inhibition of NO synthase (NOS). In addition, reoxygenation after the “point of no return”, as characterized above, greatly potentiated [Ca2+]i overload and facilitated the process of cell injury. The potentiation and facilitation of cell damage, as demonstrated by rapid massive increase of [Ca2+]i and subsequent cell death, was not blocked by NOS inhibitor,l-NAME.
Photosensitization with benzochlorin iminium salts

The photobiology of a group of iminium salts was examined. The nonfluorescent copper derivative (CDS1) had an almost undetectable triplet yield, but could catalyze phototoxic effects in cell culture and experimental animal tumors, apparently without the involvement of singlet oxygen. The Zn analog and the metal-free iminium salt both exhibited fluorescence, and were somewhat more efficacious that CDS1, perhaps because both type I and type II processes were available. The nonfluorescent Ni analog was inactive as a photosensitizer. Fluorescent probes indicated that CDS1 and its zinc analog catalyzed photodamage at mitochondrial loci, the metal-free derivative at membrane loci. Because of its very low fluorescence yield, the metal-free iminium salt showed only faint intracellular fluorescence, but the Zn analog was unusual in this regard, with irradiation leading to a photoproduct with very intense intracellular fluorescence which was not readily photobleached.
Delamination of filler-incorporated automotive epoxy adhesives from different steel substrates upon exposure to distilled water and NaCl solutions under applied bending stresses

Delamination of four filler-incorporated automotive epoxy adhesives from five different steel substrates was studied using a three-point bending device. The bent specimens were exposed to distilled water and NaCl solutions with different concentrations from 1–5 weeks. It was found that the degree of adhesive delamination increased with the concentration of the NaCl solution, and with the magnitude of the applied bending stresses. The harder the adhesives, or the higher the content of the fillers in the adhesives, the lower was the degree of the adhesive delamination. In addition, the rank of the steel substrates in terms of their bonding resistance against adhesive delamination was determined. It is believed that the adhesion between the adhesives and the steel substrates is governed by the surface roughness of the steel substrates.
Radiotracer‐based method for determining water solubility of highly insoluble compounds

Ascertaining the aqueous solubility of compounds is important in the selection of drug candidates. We describe a radiotracer method for estimating water solubility of compounds that are soluble in dimethyl sulfoxide (DMSO). Various volumes of DMSO, saturated with 127I-labeled compound and spiked with the corresponding 125I-labeled derivative, are mixed in de-ionized water and the tubes centrifuged to remove insoluble material. Since (i) the iodine-127 and iodine-125 compounds have the same solubilities and are equally distributed in the DMSO–water solution, and (ii) the nonradioactive compound is accurately weighed, dissolved in a known volume of DMSO, and then further diluted as required, the concentration of compound in solution can be calculated and plotted as a function of the DMSO-to-water ratio. Water solubility of the compound is then determined by extrapolation of the linear fit of data points to zero DMSO. As proof of the methodology, 5-iodo-2′-deoxyuridine (IUdR) and 2-iodo-8-methyl-8H-quino[4,3,2-kl]acridine (IMAc), water-soluble compounds, were assessed using 125IUdR and 125IMAc, respectively. The solubility values obtained by the radiotracer method were similar to those acquired by spectrophotometry. Values calculated for several water-insoluble compounds indicate that the radiotracer method can accurately quantify the solubility of low-molecular-weight compounds (1000–2000 Da) in the pg–ng/ml range. Copyright © 2006 John Wiley & Sons, Ltd.
The shape of the Neandertal femur is primarily the consequence of a hyperpolar body form

Neandertal femora are distinct from contemporaneous near-modern human femora. Traditionally, these contrasts in femoral shape have been explained as the result of the elevated activity levels and limited cultural abilities of Neandertals. More recently, however, researchers have realized that many of these femoral differences may be explained by the cold-adapted bodies of Neandertals vs. the warm-adapted bodies of near-modern humans. This study explicitly tests this proposed link between climate-induced body proportions and femoral shape by considering the entire hip as a unit by using geometric morphometric methods adapted to deal with articulated structures. Based on recent human patterns of variation, most contrasts in shape between the femora of Neandertals and near-modern humans seem to be secondary consequences of differences in climate-induced body proportions. These results, considered in light of hip mechanics during growth, highlight the importance of developmental and functional integration in determining skeletal form.
Elevated Peripheral Neutrophils and Matrix Metalloproteinase 9 as Biomarkers of Functional Outcome Following Subarachnoid Hemorrhage

There is growing evidence supporting the role of inflammation in early brain injury and cerebral vasospasm following subarachnoid hemorrhage (SAH). Matrix metalloproteinases (MMPs) are released by inflammatory cells and can mediate early brain injury via disruption of the extracellular matrix and mediate vasospasm by cleaving endothelin-1 into vasoactive fragments. We hypothesize that inflammation marked by neutrophil elevation and MMP-9 release in human SAH is associated with vasospasm and with poor clinical outcome. We enrolled consecutive SAH subjects (N = 55), banked serial blood and cerebrospinal fluid (CSF) samples, and evaluated their 3-month modified Rankin scores (mRS). Vasospasm was defined as >50% vessel caliber reduction on angiography 6–8 days post-SAH. A poor outcome was defined as mRS > 2. We compared blood leukocyte and neutrophil counts during post-SAH days 0–14 with respect to vasospasm and 3-month outcome. In a subset of SAH subjects (N = 35), we compared blood and CSF MMP-9 by enzyme-linked immunosorbent assay (ELISA) on post-SAH days 0–1, 2–3, 4–5, 6–8, and 10–14 with respect to vasospasm and to 3-month outcome. Persistent elevation of blood leukocyte (p = 0.0003) and neutrophil (p = 0.0002) counts during post-SAH days 0–14 are independently associated with vasospasm after adjustment for major confounders. In the same time period, blood neutrophil count (post-SAH days 2–3, p = 0.018), blood MMP-9 (post-SAH days 4–5, p = 0.045), and CSF MMP-9 (post-SAH days 2–3, p = 0.05) are associated with poor 3-month SAH clinical outcome. Neutrophil count correlates with blood MMP-9 (post-SAH days 6–8, R = 0.39; p = 0.055; post-SAH days 10–14, R = 0.79; p < 0.0001), and blood MMP-9 correlates with CSF MMP-9 (post-SAH days 4–5, R = 0.72; p = 0.0002). Elevation of CSF MMP-9 during post-SAH days 0–14 is associated with poor 3-month outcome (p = 0.0078). Neither CSF nor blood MMP-9 correlates with vasospasm. Early rise in blood neutrophil count and blood and CSF MMP-9 are associated with poor 3-month SAH clinical outcome. In blood, neutrophil count correlates with MMP-9 levels, suggesting that neutrophils may be an important source of blood MMP-9 early in SAH. Similarly, CSF and blood MMP-9 correlate positively early in the course of SAH, suggesting that blood may be an important source of CSF MMP-9. Blood and CSF MMP-9 are associated with clinical outcome but not with vasospasm, suggesting that MMP-9 may mediate brain injury independent of vasospasm in SAH. Future in vitro studies are needed to investigate the role of MMP-9 in SAH-related brain injury. Larger clinical studies are needed to validate blood and CSF MMP-9 as potential biomarkers for SAH outcome.
New estimates of silicate weathering rates and their uncertainties in global rivers

Abstract This study estimated the catchment- and global-scale weathering rates of silicate rocks from global rivers using global compilation datasets from the GEMS/Water and HYBAM. These datasets include both time-series of chemical concentrations of major elements and synchronous discharge. Using these datasets, we first examined the sources of uncertainties in catchment and global silicate weathering rates. Then, we proposed future sampling strategies and geochemical analyses to estimate accurate silicate weathering rates in global rivers and to reduce uncertainties in their estimates. For catchment silicate weathering rates, we considered uncertainties due to sampling frequency and variability in river discharge, concentration, and attribution of weathering to different chemical sources. Our results showed that uncertainties in catchment-scale silicate weathering rates were due mostly to the variations in discharge and cation fractions from silicate substrates. To calculate unbiased silicate weathering rates accounting for the variations from discharge and concentrations, we suggest that at least 10 and preferably ∼40 temporal chemical data points with synchronous discharge from each river are necessary. For the global silicate weathering rate, we examined uncertainties from infrequent sampling within an individual river, the extrapolation from limited rivers to a global flux, and the inverse model selections for source differentiation. For this weathering rate, we found that the main uncertainty came from the extrapolation to the global flux and the model configurations of source differentiation methods. This suggests that to reduce the uncertainties in the global silicate weathering rates, coverage of synchronous datasets of river chemistry and discharge to rivers from tectonically active regions and volcanic provinces must be extended, and catchment-specific silicate end-members for those rivers must be characterized. With current available synchronous datasets, we suggest that the global silicate weathering rate (Ca + Mg silicate weathering flux) was ∼2.17 (2 σ range of 1.59–2.75) × 10 12 mol/yr, and the global CO 2 consumption rates from silicate weathering was ∼7.85 (5.78–9.93) × 10 12 mol/yr. Since current synchronous datasets are not available for some rivers in tectonically active regions and highly active volcanic rocks, our estimate should be considered as lower limit of estimates. Including the estimates from volcanic provinces from Dessert et al. (2003) , the global CO 2 consumption rates from silicates can be estimated as 11.93 (9.86–14.01) × 10 12 mol/yr, which is similar to the previous estimates of Gaillardet et al. (1999) .
Schemas determining the incentive value of sales promotions

There are three types of schemas for evaluating sales promotions: schemas using cognitive algebra, schemas analogous to perceptual processes, and simple nonalgebraic heuristics. Each type of schema requires different information to evaluate a promotion. The schema a consumer uses to evaluate a promotion may therefore determine whether or not the promotion is seen as valuable. The effects of salespeople, product type, and the consumer's situation on the schemas used to evauate promotions are discussed.
Reassignment of sense codons in vivo

The genetic code maps one or more of the 61 sense codons onto a set of 20 canonical amino acids. Reassignment of sense codons to non-canonical amino acids in model organisms such as Escherichia coli has been achieved through manipulation of the cellular protein synthesis machinery. Specifically, control of amino acid pools, coupled with engineering of the aminoacyl-tRNA synthetase activity of the host, has enabled assignment of sense codons to a wide variety of non-canonical amino acids under conditions routinely used for expression of recombinant proteins. Codon reassignment is leading to important advances in protein engineering and bioorganic chemistry. Here we summarize some of those advances, and provide detailed protocols for codon reassignment.
Scene Coordinate Regression Forests for Camera Relocalization in RGB-D Images

We address the problem of inferring the pose of an RGB-D camera relative to a known 3D scene, given only a single acquired image. Our approach employs a regression forest that is capable of inferring an estimate of each pixel's correspondence to 3D points in the scene's world coordinate frame. The forest uses only simple depth and RGB pixel comparison features, and does not require the computation of feature descriptors. The forest is trained to be capable of predicting correspondences at any pixel, so no interest point detectors are required. The camera pose is inferred using a robust optimization scheme. This starts with an initial set of hypothesized camera poses, constructed by applying the forest at a small fraction of image pixels. Preemptive RANSAC then iterates sampling more pixels at which to evaluate the forest, counting inliers, and refining the hypothesized poses. We evaluate on several varied scenes captured with an RGB-D camera and observe that the proposed technique achieves highly accurate relocalization and substantially out-performs two state of the art baselines.
The disclosure of incidental genomic findings: an “ethically important moment” in pediatric research and practice

Although there are numerous position papers on the issues and challenges surrounding disclosure of incidental genomic findings involving children, there is very little research. To fill this gap, the purpose of this study was to explore the perspectives of multiple professional (N = 103) and public (N = 63) stakeholders using both interviews and focus groups. Using qualitative analysis, we identified one overarching theme, “It's hard for us; it's hard for them,” and three subthemes/questions: “What to disclose?,” “Who gets the information?,” and “What happens later?” Perspectives differed between professional (Institutional Review Board chairs, clinicians, and researchers) and public stakeholders. While professionals focused on the complexities of what to disclose, the lay public stated that parents should have all information laid out for them. Professionals pondered multiple parent and child situations, while the public identified parents as informational gatekeepers who know their children best. Professionals described the potential requirement for follow-up over time as a logistical “nightmare,” while the public believed that parents have the responsibility for managing their children's health information over time. However, the parent role as gatekeeper was seen as time limited and in need of professional support and backup. Our findings present a case for needed dialogue around what we propose as an “ethically important moment,” with the goal of protecting and respecting the viewpoints of all stakeholders when policies regarding children are developed.
Interannual and Month-to-Month Variations of Wind Speed

Abstract Spatial cross correlations and interannual and month-to-month variations of monthly mean wind speed were studied at 40 sites throughout the United States. Sites were selected on the basis of availability of 10 or more years of data from a fixed anemometer location and height and a climatological mean speed of 5 m s−1 (11 mph) or higher. Spatial cross correlations of monthly deviations from climatic means were found to be about 0.5 for sites separated less than 200 km, with annual mean wind deviations from the climatic mean correlated with coefficient value 0.32 for similarly separated sites. Applications for using nearby “climatological” site wind speed data to adjust short-term “candidate” site data are examined with several methods. The best results show only minimal improvement in estimating the long-term annual mean over that obtained from one year of on-site data. These results indicate that, for candidate wind energy site evaluation, on-site data must be relied on more than originally consi...
Trailblazing with Roadrunner

The authors look at the changes occurring in computer system design, the rise of heterogeneous computing, and the effects these changes have on high-performance computing.
Transport coefficients of dense matter in the liquid metal regime

Calcul des conductivites thermiques et electriques et de la viscosite de cisaillement de la matiere dense lorsque les ions forment un liquide
Eunuchs in Historical Perspective

This article examines the meaning of the terms ‘eunuch’ and ‘castration’ and situates these terms in an historical context. It divides castrated eunuchs into two groups, those who castrate themselves voluntarily for religious reasons and those who are castrated by others either as a punishment or in order to create an individual who is significantly different from a whole man. This second group is further divided based on the tasks for which the eunuch is prepared. These may be sexual or lie in the area of personal service. Three major court cultures are compared, Islam, Byzantium, and China, and several religious cults that encourage self-castration are also discussed.
Scaphoid fractures in children

A fracture of the scaphoid in the wrist of a 6-year-old girl and eight new cases of scaphoid fractures in children are reported.
Response facilitation and response inhibition produced by intracranial injections of brain extracts from trained donor goldfish

Three experiments are reported which bear on the issue of whether brain extracts from trained donor animals generally facilitate learning or performance or, rather, modify recipient behavior in a specific way. In Experiment I, extracts facilitated an approach response in the absence of training (learning) of the naive recipient goldfish. In Experiments II and III, extracts from brains of inhibition-trained donor fish resulted in a significantly lower level of responding than that found in recipients of brain extracts from untrained control donor fish. Four hypotheses are described (“general learning facilitation, ” “generalized performance facilitation, ” “weak specificity, ” and “strong specificity” hypotheses) in which biochemical transfer results might be considered. It is shown that the present results rule out the two general-effect hypotheses and are at the same time supportive of the weak specificity hypothesis. It is shown further that, when other published findings are considered, only the strong specificity hypothesis survives as a useful description of biochemical transfer findings.
Adhesion of Lymphoid Cells to CD44-Specific Substrata: The Consequences of Attachment Depend on the Ligand

Interactions between cell-surface adhesion receptors and immobilized specific substrata can exert profound effects on cell morphology. Using phase-contrast microscopy, we show that CD44-expressing mouse lymphoid cells display a spread morphology when adhering to CD44-specific monoclonal antibody (mAb) immobilized on plastic. This spread morphology is different from that of these same cells when adhering to immobilized hyaluronan, the natural ligand of CD44. Morphometric measurements, in combination with intracellular actin staining and fluorescence microscopy, revealed that the adhesion of lymphoid cells to hyaluronan required essentially no cytoskeletal reorganization and resulted in no fundamental change in morphology. On the other hand, cells adhering to immobilized CD44-specific mAb rearranged their actin structure and established multiple membrane contact sites (spread). Cell spreading on antibody, but not attachment to hyaluronan, was inhibited by cytoskeleton-disrupting agents. Transfection of CD44-negative lymphoid cells with full-length and tailless CD44 enabled these cells to bind to both immobilized hyaluronan and mAb. However, the transfectant lacking the cytoplasmic tail of CD44 spread only transiently on the antibody-coated surface. Our results suggest that CD44 may mediate lymphocyte attachment to its carbohydrate ligand hyaluronan by mechanisms broadly similar to those used by selectins. When immobilized CD44-specific antibody is the ligand, however, CD44 may regulate the activity of the cytoskeleton by mechanisms broadly similar to those used by integrins. In the latter case, the cytoplasmic domain of CD44 contributes to cell spreading.
Immunophenotypic transformation from acute undifferentiated leukemia to burkitt's-like acute lymphoblastic leukemia

Progression of more differentiated to less differentiated malignant phenotypes has been described infrequently during the natural evolution or at relapse of treated hematopoietic malignancies. This report describes an unusual instance of immunophenotypic transformation from an immunologically undifferentiated acute leukemia to a leukemia that at relapse possessed morphologic and immunologic markers characteristic of a Burkitt's-like acute lymphoblastic leukemia. A 26-year-old man initially presented with pancytopenia and a bone marrow diffusely replaced with blast cells morphologically most consistent with a French-American-British L2 subclassification. The surface immunophenotype of the blasts at diagnosis showed HLA-DR surface antigen but no myeloid, lymphoid, or immunoglobulin determinants. Despite successful induction and ongoing consolidation chemotherapy, the patient had a relapse five months after diagnosis; blast cells at relapse demonstrated marked cytoplasmic vacuolation consistent with a Burkitt's-like L3 acute lymphoblastic transformation. Immunophenotypic analysis revealed the presence of restricted immunoglobulin determinants (mu heavy chain and kappa light chain), as well as two separate B lineage surface determinants (BA-1 and B-1). Immunophenotypic transformations may reflect the presence of either a multiclonal or multipotent leukemic population; documentation of the frequency of such transformations and genomic analysis of the transformed subpopulations may be helpful in furthering the understanding of molecular mechanisms involved in leukemogenesis.
The Role of the Buried Aspartate of Escherichia coliThioredoxin in the Activation of the Mixed Disulfide Intermediate

Abstract The structurally homologous protein disulfide isomerases and thioredoxins exhibit a 105 variation of redox equilibria. It is demonstrated that the kinetic distinction among these protein family members lies primarily in the rate of breakdown of the mixed disulfide intermediate. The conserved buried acid group serves as a proton transfer catalyst for the buried active site cysteine in the formation and breakdown of the mixed disulfide. The reduction rate of Escherichia coli thioredoxin by dithiothreitol is directly proportional to the fraction of Asp-26 in the protonated form over the pH range of 6–9. The kinetic role of Asp-26 is further probed via differential solvent kinetic isotope effect measurements versus a D26N variant. The differential solvent isotope effect of 0.6 is consistent with a direct proton donation to the thiolate leaving group (Cys-35) via an enforced general acid catalysis by trapping mechanism. Such a donation necessitates a structural rearrangement as these two buried side chains are separated by 6 A in both the oxidized and reduced forms of the protein.
Nuclear magnetic resonance determination of the isotope effect in titanium tritide

Abstract Nuclear magnetic resonance methods have been used to observe an isotope effect for hydrogen diffusion in TiH 1.5 . The observed mass dependence of the atomic jump frequency and activation energy is consistent with the analysis of LaClaire.
Linear dynamic mechanical properties of an SBS block copolymer

Dynamic viscosity and elastic modulus for a low molecular weight styrene-butadiene-styrene (SBS) block copolymer ate measured as a function of temperature (80-170°C) and frequency using the eccentric rotating disc geometry. These linear properties are superimposed to yield master curves each of which exhibits two branches below different (critical) reduced frequencies. At lower temperatures, the non-Newtonian behavior characteristic of SBS block copolymers is observed. In contrast, Newtonian response occurs at higher temperatures. As a consequence, plots of the viscoelastic properties vs temperature exhibit discontinuities below the critical frequencies, reflecting a narrow transition at about 142°C. Above this temperature, it is inferred, consistent with the equality of dynamic and steady state viscosities, that the polystyrene (S) blocks, existent in dispersed domains at low temperatures, exceed a critical degree of compatibility with the continuous polybutadiene phase. The activation energies indicate that the S blocks affect the temperature dependence of the dynamic properties in proportion to their presence in an interphase which is assumed to continuously grow in size as temperature is raised to the transition temperature. Below the critical reduced frequencies, it is inferred that S domain disruption may increasingly occur in conjunction with the observed property enhancement due to these domains, relative to the miscible blocks, as reduced frequency is lowered. However, above these frequencies, the presence of frequency-temperature superposition implies that the S domains and the miscible blocks are equivalent in their effects on properties. At still higher reduced frequencies, the domains present at the low temperatures studied are assumed to remain intact, but plateau behavior similar to the response characteristic of homopolymers is observed.
In situ water motion and nutrient uptake by the giant kelp Macrocystis pyrifera

Rates of NO 3 - uptake by individual blades of Macrocystis pyrifera (L.) C. Agardh were measured at different flow rates in the laboratory. Dissolution rates of hemispherical, plaster buttons attached to the blade surface provided a relative measure of flow rates over blades used in uptake experiments and also over intact blades of adult kelp plants in situ (Laguna Beach, California, USA; 1981). Laboratory results indicated that uptake was saturated at a flow rate equivalent to 2.5 cm s-1 current velocity. Flow rates over intact blades in situ always exceeded this uptake saturation level. Wave surge and movement of plant surfaces relative to the surrounding water provided sufficient flow to saturate uptake, even in a dense kelp canopy during low-current and calm sea-state conditions.
Hydrobiogeochemical Controls on Riparian Nutrient and Greenhouse Gas Dynamics: 10 Years Post-Restoration†

Little is known about the impact of agricultural legacy on subsurface biogeochemical processes in the years following restoration of riparian wetlands (WLs). More knowledge is also needed on the relative importance of seasons, precipitation events, and inputs of water and nutrients driving nitrogen (N), phosphorus (P), sulfur (S), and greenhouse gas (GHG) (N2O, CO2, CH4) dynamics in these systems. This investigation of a riparian zone comprising a restored WL area and a nonrestored well-drained alluvium (AL) area in the United States Midwest revealed that despite successful hydrological restoration a decade earlier, biogeochemical conditions in the WL area remained less anoxic than in natural WLs, and not significantly different from those in the AL area. No significant differences in N, P, S, and C compound concentrations or fluxes were observed between the AL and WL areas. Over the duration of the study, nitrate (NO3−) and soluble reactive phosphorus appeared to be primarily driven by hillslope contributions. Ammonium (NH4+), sulfate (SO42−), and CO2 responded strongly to seasonal changes in biogeochemical conditions in the riparian zone, while N2O and CH4 fluxes were most influenced by large rewetting events. Overall, our results challenge overly simplistic assumptions derived from direct interpretation of redox thermodynamics, and show complex patterns of solutes and GHGs at the riparian zone scale.
A roadmap for the immunomics of category A-C pathogens.

Summary The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), recently awarded 14 contracts to fund the Large-Scale Antibody and T Cell Epitope Discovery Program. This initiative is designed to identify immune epitopes from selected infectious agents utilizing complementary methods for epitope discovery. NIAID will make information on each newly identified epitope freely available to scientists worldwide through the Immune Epitope Database and Analysis Resource (IEDB), currently under development. On October 12–14, 2004, representatives of NIAID met in San Diego, California, with a group of investigators from various research institutions to discuss progress and plans for the large-scale epitope discovery projects and for the establishment of the IEDB. It is anticipated that these initiatives will establish detailed maps of immune reactions toward several important complex pathogens, which in turn will foster development of new diagnostic, immune-based therapeutic, and vaccine programs. Herein is an account of the meeting and its results.
Building a partnership for computer science education

The University of California San Diego (UCSD) piloted a new undergraduate introduction to computer science (CS) principles in fall 2010. The course was contextual, conceptual, and constructivist in its approach to programming; building interest and enthusiasm for the "magic" of computing; and designed to become a new high school AP Computer Science Principles course (to precede AP CS A)[2].This paper describes a set of activities that set the stage to introduce the new CS Principles course into San Diego area high schools -- a region with many districts and a highly diverse student population -- truly a significant challenge. This exploratory project conducted by the San Diego Supercomputer Center (SDSC) at UCSD identified essential decision makers and stakeholders, and built and/or strengthened the strategic collaborative networks necessary to support sustainable change in the region's K-12 computer science education programs.SDSC identified core leadership partners from UCSD, from San Diego State University (with the largest teacher preparation program in the region), the San Diego County Office of Education, and the San Diego Computer Science Teachers Association.With guidance and introductions from these core leadership partners, project PIs met with district administrators, technology specialists, and high school teachers who shared the project goals. In turn, these contacts provided introductions and opportunities for project PIs to present the case for the course to elected officials and key district decision-makers. Guided by input from these meetings, the core leadership partnership developed and achieved an agenda of objectives to build the collaborative networks needed for sustainable regional implementation of the course. Those strategic objectives included:• Identify protocols, processes, and decision criteria in each school and district; outline strategies for their effective use;• Gain endorsements needed for district-wide implementation;• Identify leaders within each district (teachers, professional development specialists, technology specialists, and administrators) willing to become advocates/ambassadors for the new (and not-yet AP) CS Principles course; and• Recruit and train a Teacher Leadership Team to pilot test the "Computer Science Principles" course content and pedagogy in their own high school classrooms, and provide formative feedback to guide wider professional development and course implementation.
Long-term immunosuppression, without maintenance prednisone, after kidney transplantation.

Successful clinical allotransplants only became possible with the development of immunosuppression. Initially, 6-mercaptopurine, or its derivative azathioprine (AZA), was used.1–3 Shortly thereafter, Starzl et al4 reported improved graft survival when AZA was combined with prednisone. Since that time, transplant clinical research has focused on improving short- and long-term graft survival while simultaneously minimizing immunosuppression-related complications. Prednisone has a well-defined side effect profile, which includes hypertension, osteoporosis (and fractures), avascular necrosis, cataracts, mood alterations, posttransplant diabetes, easy bruisability, and skin changes. Some of these side effects are related to the cumulative steroid dose.5 Others develop rapidly posttransplant6 and can occur early, even with use of relatively low-dose steroids.7–9 Consequently, even early in the history of transplantation, attempts were made to minimize the daily prednisone dose.10 In general, however, kidney transplant recipients who began prednisone at the time of their transplant tended to have better long-term graft survival than those who did not take prednisone. Throughout the 1980s and 1990s, many transplant centers studied whether selected, clinically well, immunologically low-risk kidney transplant recipients, without a previous acute rejection episode, could undergo prednisone withdrawal. Those studies showed that, even in carefully selected recipients, prednisone withdrawal was associated with an increased risk of acute rejection11,12 and of graft loss.12 Of particular concern was a Canadian multicenter, prospective, randomized study in which recipients on cyclosporine (CSA) and prednisone, without active rejection, were randomized at 90 days posttransplant to continue on CSA and either low-dose prednisone or placebo. The Canadian study found no difference in graft survival for the first 3 years posttransplant, but thereafter the steroid-free group had significantly worse graft survival (P = 0.03 versus the low-dose prednisone group).13 More recently, with the introduction of new, more potent immunosuppressive agents, interest in steroid-sparing protocols has resurged. Two prospective randomized studies of steroid withdrawal in recipients on CSA, mycophenolate mofetil (MMF), and prednisone showed an increased incidence of acute rejection episodes in the steroid withdrawal arm.14,15 In contrast, numerous other studies have now shown a low acute rejection rate when steroids are completely avoided or discontinued in the first week after kidney or simultaneous kidney-pancreas transplants.16–24 Outcome at 1 year posttransplant has been excellent with protocols incorporating prednisone avoidance or rapid discontinuation. Yet concern remains, fueled by the results of the Canadian study, that long-term outcome will be worse in prednisone-free recipients. We herein report 4-year outcome in a cohort of kidney transplant recipients who discontinued their prednisone in the first posttransplant week.
"Single suture" for exposure of the heart in left ventricular assist device placement.

Using the "single suture" technique described for exposure of the heart during off-pump coronary surgery, all surfaces of the heart may be exposed with little hemodynamic compromise. Using this technique, the apex of the heart is easily elevated for left ventricular assist device (LVAD) insertion in patients with either ischemic or dilated cardiomyopathy. This technique may provide the groundwork for routine placement of LVADs without the use of cardiopulmonary bypass.
Resistivity and oxygen content of indium tin oxide films deposited at room temperature by pulsed-laser ablation

Transparent, conductive indium tin oxide (ITO) films were fabricated by pulsed-laser deposition on substrates held at room temperature. We investigated the relationship between electrical/optical properties of the films and the material stoichiometry, measured by Rutherford backscattering. The lowest resistivity films (∼4×10−4 Ω cm) have excessive oxygen compared with the stoichiometric composition ITO. After annealing in argon at 400 °C for 1.5 h, the oxygen-to-(indium+tin) ratio approaches the stoichiometric composition of 1.5 and resistivities of annealed samples are ∼2.5×10−4 Ω cm. The room-temperature ITO resistivity dependence on chamber gas pressure is explained in terms of a gas-dynamic model and oxygen content of the film.
NKp30-dependent cytolysis of filovirus-infected human dendritic cells

Understanding how protective innate immune responses are generated is crucial to defeating highly lethal emerging pathogens. Accumulating evidence suggests that potent innate immune responses are tightly linked to control of Ebola and Marburg filoviral infections. Here, we report that unlike authentic or inactivated Ebola and Marburg, filovirus-derived virus-like particles directly activated human natural killer (NK) cells in vitro, evidenced by pro-inflammatory cytokine production and enhanced cytolysis of permissive target cells. Further, we observed perforin- and CD95L-mediated cytolysis of filovirus-infected human dendritic cells (DCs), primary targets of filovirus infection, by autologous NK cells. Gene expression knock-down studies directly linked NK cell lysis of infected DCs to upregulation of the natural cytotoxicity receptor, NKp30. These results are the first to propose a role for NK cells in the clearance of infected DCs and the potential involvement of NKp30-mediated cytolysis in control of viral infection in vivo. Further elucidation of the biology of NK cell activation, specifically natural cytotoxicity receptors like NKp30 and NKp46, promises to aid our understanding of microbial pathology.
Replacement of mitral valve posterior chordae tendineae with expanded polytetrafluoroethylene suture: a finite element study.

Background and aims Expanded polytetrafluoroethylene (ePTFE) suture has been used clinically for replacement of ruptured mitral valve chordae tendineae. The purpose of this study was to assess mitral valve function after posterior chordal replacement with ePTFE suture. Methods A three-dimensional finite element computer model of the mitral valve was used, which incorporated geometry, regional tissue thickness, collagen fiber orientation, and anisotropic material properties for the leaflets, interface, and chordae tendineae. To simulate chordal rupture, four marginal and four basal chordae were removed from the posterior leaflet. Chordal replacement was simulated using two elements with the physical and material properties of 2-0 ePTFE suture. Systolic loading pressures were applied. Results The chordal rupture model demonstrated posterior leaflet prolapse, abnormal stress concentrations, potential regurgitation, and elevated chordal stress. Conversely, the chordal replacement model corrected the prolapse and returned chordal stress to normal levels. However, stress concentrations were shown at suture attachment points. Conclusions This integrated mitral valve finite element model provides a tool to investigate the performance of the valve system. In this study, we have shown that 2-0 ePTFE suture replacement of ruptured posterior chordae tendineae returns the valve to a near normal state, in terms of leaflet stress and coaptation, and chordal stresses.
Physical and Social Conditions Affecting Recreation Site Preferences

Recreation managers have focused much of their efforts on the analysis of relationships between perceived user satisfaction, participation levels, and the manipulation of supply features whereas other managers have been concerned with unwanted social interactions that take place at recreation facilities. This study focuses upon an analysis both of the environmental preferences of recreators and of the social conditions present at facilities which affect visitor satisfaction and use. Preferences for five attributes of trail areas within Chicago forest preserves were examined so that a predictive model for visitor satisfaction could be derived and used to evaluate alternative management strategies for trail design. The number of changes in views contributed more to visitor satisfaction than the type of trail surface, trail length, and the type of terrain on the trail. Proximity to residence was more important than the combination of all other physical characteristics. In addition, a positive correlation was...
Islam and the Politics of Enchantment

The North American public sphere is suffused with claims and counter-claims about the relationship between Islam and violence. Schools and publishers have responded with training programmes for teachers and curriculum units for students introducing them to the Middle East and its dominant religious tradition. Such programmes are often accused by local parents and national intellectuals of pandering to Muslim sensitivities by whitewashing distasteful historical events and even proselytizing young people. Focusing on a 2002 lawsuit filed against California's Byron Union School District, by parents upset by a classroom role-playing exercise on Islam, this paper argues that political fears about terrorist infiltration into US society are building on powerful emotional and cultural concerns about the nature of ritual and the spiritual safety of children exposed to information about other religions. By encouraging public education as a response to political and cultural tensions, educators may in fact be heightening the public's concerns about Islam as a comprehensive threat.