cssi/SciSciGPT-SciSciNet huggingface dataset:
Submesh Allocation in Mesh Multicomputers Using Busy-List

A new approach is proposed for dynamic submesh allocation in mesh-connected multicomputer system, which supports a multiuser environment. The proposed strategy effectively prunes the search space by searching for free submeshes on the corners of allocated (busy) submeshes along with the four corners of the mesh system. A submesh is selected with the potential of causing the least amount of fragmentation in the system. The proposed strategy possesses complete submesh recognition capability; it is a best-fit strategy, as well. Existing strategies do not provide this combination of capabilities. The deallocation time and memory overhead are shown to be constant in that they do not grow with the size of the mesh. To demonstrate effectiveness, the performance of the proposed strategy is compared against all existing schemes. Simulation results indicate that the proposed strategy outperforms existing ones in terms of parameters such as average delay in honoring a request, standard deviation of delay, average allocation time, average deallocation time, and amount of memory required. The proposed scheme achieves a 20 to 30% improvement in the average waiting delay over the best performing existing algorithm to date. Our scheme is shown to be applicable to torus-connected multicomputers as well, with only minor modifications. The scheme can also be used for submesh allocation with failures.
Poly(A) Tail Recognition by a Viral RNA Element Through Assembly of a Triple Helix

Kaposi's sarcoma-associated herpesvirus produces a highly abundant, nuclear noncoding RNA, polyadenylated nuclear (PAN) RNA, which contains an element that prevents its decay. The 79-nucleotide expression and nuclear retention element (ENE) was proposed to adopt a secondary structure like that of a box H/ACA small nucleolar RNA (snoRNA), with a U-rich internal loop that hybridizes to and protects the PAN RNA poly(A) tail. The crystal structure of a complex between the 40-nucleotide ENE core and oligo(A)(9) RNA at 2.5 angstrom resolution reveals that unlike snoRNAs, the U-rich loop of the ENE engages its target through formation of a major-groove triple helix. A-minor interactions extend the binding interface. Deadenylation assays confirm the functional importance of the triple helix. Thus, the ENE acts as an intramolecular RNA clamp, sequestering the PAN poly(A) tail and preventing the initiation of RNA decay.
Damage at negative triaxiality

Abstract The damage process under compressive hydrostatic stress in ductile metals has been observed in many experiments. However, no damage theory explains the physical mechanism of damage due to compressive hydrostatic stress in ductile metals. Recently, one possible physical mechanism of shear damage at low and negative stress triaxiality (The stress triaxiality is defined as ( ( 1 / τ eqv ) ( τ k k / 3 ) ) where τ eqv = ( 2 / 3 ) τ ′ : τ ′ , τ is the Kirchhoff stress tensor. Triaxiality in this paper refers to the stress triaxiality defined above.) was shown to be the development of tensile hydrostatic stress due to grain-to-grain interaction (Kweon, S., Beaudoin, A.J., McDonald, R.J., 2010. Experimental characterization of damage processes in aluminum AA2024-O. Journal of Engineering Materials and Technology 132.) Kweon (2009. Edge cracking in rolling of an aluminum alloy AA2024-O. Mechanical Science and Engineering, University of Illinois, Urbana.) proposed a mesoscale theoretical framework that can be used to quantitatively investigate the amount of shear damage at all triaxiality levels, incorporating the physical mechanism of shear damage. This theoretical framework is based on crystal plasticity and the theory of void growth due to hydrostatic stress. The damage process at negative triaxiality is particularly important since many industrial processes for metals involve a compressive hydrostatic stress state such as rolling. Using the mesoscale theoretical framework, damage at negative triaxiality is theoretically quantified. It is shown that damage does exist at small negative triaxiality, and that the shear deformation component drives damage in the small negative triaxiality regime.
Significance of radiographic abnormalities in patients with tibial stress injuries: correlation with magnetic resonance imaging

The objective was to correlate radiographic findings with magnetic resonance imaging (MRI) findings in patients with suspected tibial stress injuries in order to determine the significance of radiographic signs of stress injury in these individuals. The study group consisted of 80 patients with suspected tibial stress injuries who underwent a radiographic and MR examination of the tibia. Nineteen patients had bilateral involvement. Thus, a total of 99 tibias were evaluated. All radiographs and MR examinations were retrospectively reviewed, 1 month apart, in consensus by two musculoskeletal radiologists. The radiographs were reviewed without knowledge of the site of the clinical symptoms. Fisher’s exact tests were used to determine the association between a positive radiograph and the presence of various MRI signs of a high-grade stress injury. There was a strong association between the presence of periosteal reaction on radiographs at the site of the clinical symptoms and a Fredericson grade 4 stress injury on MRI. The presence of periosteal reaction on radiographs at the site of clinical symptoms is predictive of a high-grade stress injury by MRI criteria.
Abstract A38: DDB2 suppresses tumorigenicity of ovarian cancer cells through reducing the subpopulation of cancer stem cells

Ovarian cancer is an extremely aggressive disease associated with a high percentage of recurrence and chemotherapy resistance. Damaged DNA binding protein 2 (DDB2) is a 48-kDa protein originally identified as a component of the damage-specific DNA-binding heterodimeric complex DDB. Besides the known ability of DDB2 protein to bind ultraviolet (UV)-damaged DNA and serving as the initial damage recognition factor during nucleotide excision repair (NER). DDB2 was also reported to be involved in the promotion of apoptosis to reduce cisplatin resistance of ovarian cancer cells, control of cell migration, invasiveness and breast tumor progression, as well as suppression of metastasis of colon cancer through a transcriptional regulatory mechanism. Here we show that DDB2 overexpression in human ovarian cancer cell line CP70 suppressed its capability to recapitulate tumors in athymic nude mice, as well as the growth of these cells cultured in semisolid media. Flow cytometry analyses indicate that DDB2 overexpression in CP70 cells reduced the abundance of CD117 + cells and ALDH + cells, which are believed to be markers of cancer stem cells (CSCs) in ovarian cancer. In contrast, downregulation of DDB2 in ovarian cancer cell line A2780 increased the percentage of ALDH + cells. In addition, we analyzed the expression level of DDB2 in the putative CSCs isolated from various ovarian cancer cell lines, and demonstrated that DDB2 expression is decreased in the CSCs in comparison with their parental bulk tumor cells. Overexpression of DDB2 in the ovarian CSCs reduced the expression of CSC markers, e.g., Sox2 and Nanog. In addition, overexpression of DDB2 in CSCs isolated from ovarian cancer cell line SKOV-3 also decreased the tumorigenicity of these cells in NOD/SCID mice. In summary, our data suggest that DDB2 suppresses tumorigenicity of ovarian cancer cells through reducing the CSCs pool in cancer cells. Thus, increasing the expression of DDB2 may provide a molecular strategy to inhibit the recurrence of ovarian cancer. (Supported by NIH R01 grant CA151248 to QEW) Citation Format: Chunhua Han, Ran Zhao, John Kroger, Xingluo Liu, Qi-En Wang. DDB2 suppresses tumorigenicity of ovarian cancer cells through reducing the subpopulation of cancer stem cells. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr A38.
Some Experiments With a Supersonic Axial Compressor Stage

Between 1970 and 1974, ten variants of a supersonic axial compressor stage were designed and tested. These included two rotor configurations, three rotor tip clearances, addition of boundary-layer control consisting of vortex generators on both the outer casing and the rotor, and the introduction of slots in the stator vanes. Design performance objectives were a stage total pressure ratio of 3.0 with an isentropic efficiency of 0.82 at a tip speed of 1600 ft/s (488 m/s). The first configuration passed only 70 percent of design flow at design speed, achieving a stage pressure ratio of 2.25 at a peak stage isentropic efficiency of 0.61. The rotor was grossly separated. The tenth variant passed 91.4 percent of design flow at design speed, producing a stage pressure ratio of 3.03 with an isentropic efficiency of 0.75. The rotor achieved a pressure ratio of 3.59 at an efficiency of 0.87 under the same conditions. Major conclusions were that design tools available today would undoubtedly permit the original goals to be met or exceeded. However, the application for such a design is currently questionable because efficiency goals considered acceptable for most current programs have risen considerably from the level considered acceptable at the inception of this effort. Splitter vanes placed in the rotor permitted very high diffusion levels to be achieved without stalling. However, viscous effects causing three-dimensional flows violating the assumption of flow confined to concentric stream tubes were so strong that a geometry optimization does not appear practical without a three-dimensional, viscous analysis. Passive boundary-layer control in the form of vortex generators and slots does appear to offer some benefit under certain circumstances.
The interacting boson model and the structure of 182Hg

Abstract It is demonstrated that the interacting boson model is completely consistent with newly observed energy levels in 182 Hg. This is accomplished by making a slight change in only one of the parameter values previously used.
Differential use of Fas ligand and perforin cytotoxic pathways by donor T cells in graft-versus-host disease and graft-versus-leukemia effect

In allogeneic bone marrow transplantation (BMT) donor T cells are primarily responsible for antihost activity, resulting in graft-versus-host disease (GVHD), and for antileukemia activity, resulting in the graft-versus-leukemia (GVL) effect. The relative contributions of the Fas ligand (FasL) and perforin cytotoxic pathways in GVHD and GVL activity were studied by using FasL-defective or perforin-deficient donor T cells in murine parent --> F1 models for allogeneic bone marrow transplantation. It was found that FasL-defective B6.gld donor T cells display diminished GVHD activity but have intact GVL activity. In contrast, perforin-deficient B6.pfp(-/-) donor T cells have intact GVHD activity but display diminished GVL activity. Splenic T cells from recipients of B6.gld or B6.pfp(-/-) T cells had identical proliferative and cytokine responses to host antigens; however, splenic T cells from recipients of B6.pfp(-/-) T cells had no cytolytic activity against leukemia cells in a cytotoxicity assay. In experiments with selected CD4(+) or CD8(+) donor T cells, the FasL pathway was important for GVHD activity by both CD4(+) and CD8(+) T cells, whereas the perforin pathway was required for CD8-mediated GVL activity. These data demonstrate in a murine model for allogeneic bone marrow transplantation that donor T cells mediate GVHD activity primarily through the FasL effector pathway and GVL activity through the perforin pathway. This suggests that donor T cells make differential use of cytolytic pathways and that the specific blockade of one cytotoxic pathway may be used to prevent GVHD without interfering with GVL activity.
Understanding drug resistance for monotherapy treatment of HIV infection

The purpose of this study was to investigate strategies in the monotherapy treatment of HIV infection in the presence of drug-resistant (mutant) strains. A mathematical system is developed to model resistance in HIV chemotherapy. It includes the key players in the immune response to HIV infection: virus and both uninfected CD4+ and infected CD4+ T-cell populations. We model the latent and progressive stages of the disease, and then introduce monotherapy treatment. The model is a system of differential equations describing the interaction of two distinct classes of HIV—drug-sensitive (wild type) and drug-resistant (mutant)—with lymphocytes in the peripheral blood. We then introduce chemotherapy effects. In the absence of treatment, the model produces the three types of qualitative clinical behavior—anuninfected steady state, andinfected steady state (latency), andprogression to AIDS. Simulation of treatment is provided for monotherapy, during theprogression to AIDS state, in the consideration of resistance effects. Treatment benefit is based on an increase or retention in CD4+ T-cell counts together with a low viral titer. We explore the following treatment approaches: an antiviral drug which reduces viral infectivity that is administered early—when the CD4+ T-cell count is ≥300/mm3, and late—when the CD4+ T-cell count is less than 300/mm3. We compare all results with data. When treatment is initiated during the progression to AIDS state, treatment prevents T-cell collapse, but gradually loses effectiveness due to drug resistance. We hypothesize that it is the careful balance of mutant and wild-type HIV strains which provides the greatest prolonged benefit from treatment. This is best achieved when treatment is initiated when the CD4+ T-cell counts are greater than 250/mm3, but less than 400/mm3 in this model (i.e. not too early, not too late). These results are supported by clinical data. The work is novel in that it is the first model to accurately simultate data before, during and after monotherapy treatment. Our model also provides insight into recent clinical results, as well as suggests plausible guidelines for clinical testing in the monotherapy of HIV infection.
Photosynthetic acclimation to elevated CO2 in a sunflower canopy

Sunflower canopies were grown in mesocosom gas exchange chambers at ambient and elevated CO 2 concentrations (360 and 700 ppm) and leaf photosynthetic capacities measured at several depths within each canopy. Elevated [CO 2 ] had little effect on whole-canopy photosynthetic capacity and total leaf area, but had marked effects on the distribution of photosynthetic capacity and leaf area within the canopy. Elevated [CO 2 ] did not significantly reduce the photosynthetic capacities per unit leaf area of young leaves at the top of the canopy, but it did reduce the photosynthetic capacities of older leaves by as much as 40%. This effect was not dependent on the canopy light environment since elevated [CO 2 ] also reduced the photosynthetic capacities of older leaves exposed to full sun on the south edge of the canopy. In addition to the effects on leaf photosynthetic capacity, elevated [CO 2 ] shifted the distribution of leaf area within the canopy so that more leaf area was concentrated near the top of the canopy. This change resulted in as much as a 50% reduction in photon flux density in the upper portions of the elevated [CO 2 ] canopy relative to the ambient [CO 2 ] canopy, even though there was no significant difference in the total canopy leaf area. This reduction in PFD appeared to account for leaf carbohydrate contents that were actually lower for many of the shaded leaves in the elevated as opposed to the ambient [CO 2 ] canopy. Photosynthetic capacities were not significantly correlated with any of the individual leaf carbohydrate contents. However, there was a strong negative correlation between photosynthetic capacity and the ratio of hexose sugars to sucrose, consistent with the hypothesis that sucrose cycling is a component of the biochemical signalling pathway controlling photosynthetic acclimation to elevated [CO 2 ].
A generalized shape descriptor from wire frame models on a CAD/CAM system

Abstract One of the goals of geometric modeling is to enable the construction of a central database for information storage, retrieval, and updating of three-dimensional mechanical components, assemblies, and systems. Because the information is intended for a wide variety of purposes, a geometric model must not only be complete but also be neutral. Therefore, the vital issue is how to best represent the fundamental geometric data. An algorithm is developed for the automated conversion of wire frame data to solid geometric which would give the combined advantages of easy data input and the enormous descriptive power of solid geometric form. How the translated data could be interpreted and coded for manufacturing applications is also explained. The concept of a generalized shape descriptor has been introduced in this context.
Relationship of hemolymph juvenile hormone-binding protein to lipophorin in Leucophaea maderae

Abstract Monoclonal antibodies (MAb) specific for the hemolymph 220 kD juvenile hormone-binding protein (JHBP) of the cockroach, Leucophaea maderae, were used to further characterize the JHBP. Spleen cells, from mice immunized with semipurified hemolymph JHBP, were fused with myeloma cells to produce hybridomas secreting antibodies specific for the hemolymph 220 kD JHBP. Positive clones were recloned and rescreened by the same methods, resulting in the establishment of five cell lines producing IgG2a anti-hemolymph JHBP antibodies. Using MAb against the 220 kD hemolymph JHBP, it was demonstrated by Western blot analysis that the 220 kD JHBPs present in both ovarian and egg case extracts have antigenic determinants similar to those of the hemolymph JHBP. In addition, both the 275 and 220 kD JHBPs, synthesized and secreted by fat body maintained in vitro, were detected by anti-hemolymph JHBP antibody, demonstrating that the two media proteins and the JHBP in the ovary share identical antigenic determinants. To determine if there is a relationship between hemolymph JHBP and lipophorin, hemolymph proteins were separated on potassium bromide gradients. Gradient analysis confirmed that the lipophorin complex bound JH and that the 220 kD JHBP is apolipophorin I (apolp I). The apolp I specific MAb did not cross-react with apoliphorin II (apolp II).
Mathematics education in Turkey: at the crossroads of cultural, political and economic currents

In this opening introductory article to the issue of ZDM focused on mathematics education in Turkey, a short survey of the deep historical and cultural foundations of modern day Turkey is offered. This is followed by an outline of the development of researchers, as well as doctoral programs in mathematics education at universities in Turkey. The article also summarizes recently completed influential dissertations in Turkey and explains the aims and scope of this particular issue in relation to its conception and development.
Mixed convection in an isothermal horizontal tube: some recent theories

Abstract Comparison is made between an earlier analysis by the author and more recent theoretical investigations of mixed convection in an isothermal horizontal tube. It is again substantiated that the primary parameter for determining the bulk-temperature rise under buoyancy-dominated conditions is given by the fourth root of the Rayleigh number divided by the Graetz number. The theory is shown to correlate existing data with an RMS deviation of ≅ 8% for water and 15% for ethyl alcohol and 80 20 glycerol water. Although derived for a large-Prandtl-number fluid, it is found that the theory can equally well describe available data in air.
Initiating cultures of Halesia and Malus: influence of flushing stage and benzyladenine

Shoot tips ofHalesia carolina L. andMalus domestica Borkh. ‘Golden Delicious’ collected at various times during the spring growth flush varied considerably in their ability to initiate shoot proliferating cultures. Shoot tips collected during, or at the end of, the period of most rapid shoot elongation exhibited weak shoot proliferation potential, while shoot tips collected before or after this period were capable of strong shoot proliferationin vitro. Benzyladenine concentrations in the culture media above 22.5 µM (Halesia) or 44.5 µM (Malus) were inhibitory during the period between bud break and rapid shoot elongation. Benzyladenine concentrations of 22.5 or 44.5 µM were useful in enhancing shoot proliferation potential in shoot tips collected after the period of rapid shoot elongation, but before the onset of summer dormancy. Benzyladenine concentration did not affect the shoot proliferation potential of shoot tips collected during the rapid shoot elongation phase of the spring growth flush.Halesia andMalus shoot tips behaved similarly in this study. For deciduous woody perennials, the time of explant collection for culture initiation could be refined on the basis of these results.
Effects of transection and reanastomosis on postprandial jejunal transit and contractile activity

Background. The purpose of this study was to determine how transection and reanastomosis of the intestinal wall influences postprandial motor activity and transit in the small intestine. Methods. Six dogs were each instrumented with 12 strain gauge transducers, two collection cannulas, and an infusion catheter defining a 100 cm study segment in the midjejunum. The animals underwent baseline measurements of postprandial motor activity and transit rate after 650 kcal solid and liquid meals. Postprandial motor activity was analyzed by computer methods that identify frequency, duration, amplitude, and propagation behavior of smooth muscle contractions. After the baseline measurements were performed, each animal underwent transection and reanastomosis of the intestinal wall at sites marked during the initial laparotomy. Measurements of postprandial motor activity and transit were repeated and compared with control values. Results. Transection decreased frequency, amplitude, and percent propagation for postprandial contractions. Total propagating area per minute significantly decreased from 382±20 gram-seconds/minute to 190±66 gram-seconds/minute after transection (p Conclusions. Transection and reanastomosis of the intestinal wall changes the temporal and spatial organization of contractions distal to the transection site. The net result is fewer distally propagating contractions and slower intestinal transit.
Perceptions of Drought in the Ogallala Aquifer Region

Farmers of the Ogallala Aquifer region of the Great Plains in the western United States were interviewed concerning their perceptions of drought, weather and climate changes, aquifer conditions, and the adaptive strategies used to cope with these. The results of these surveys parallel and refine the results reported by Saarinen in 1966: Farmers recall classic droughts and the most recent years as drought; intermediate years and droughts are lost from memory. A pattern of perception is suggested by these results wherein experience influences both definition and memory, which in turn affect expectations of the particular environmental event. People's perceptions, expectations, and adaptive responses to recurrent environmental stimulae, such as drought, are related to their direct experiences. When one's experience restricts his or her view of the potential variance in meteorological or other environmental events, however, that restriction may lead to inappropriate or insufficient response to environmental h...
A Genetic Algorithm Approach to Price-Based Unit Commitment

Deregulation creates competition amongst generator companies. The generator company objectives are to maximize their profit and to place proper bids in the market. In order to do this they need to determine the schedule and operating points based on the load and price forecasts. The traditional unit commitment problem aims at minimizing the cost of operation subject to fulfillment of demand. However in a deregulated environment the traditional unit commitment objective needs to be changed to maximization of profit with relaxation of the demand fulfillment constraint. This paper applies a genetic algorithm technique to price based unit commitment (PBUC) for GENCO with 3 generators and compares the solution with that obtained by dynamic programming. Proposed algorithm can be extended to 'n' number of generators.
Oral Corticosteroid Use Is Effective for Cutaneous Hemangiomas: An Evidence-Based Evaluation

Objectives To determine the efficacy of systemic corticosteroid therapy in treating enlarging, problematic cutaneous hemangiomas and to assess the relationship of dose to response and adverse effects. Design A quantitative systematic literature review was performed and inclusion and exclusion criteria were applied. Setting Patients were treated in primary care, referral centers, and institutional practices. Most patients were ambulatory, although some required hospitalization. Patients Inclusion criteria were original case series with a minimum of 5 patients with enlarging, problematic cutaneous hemangiomas treated with systemic corticosteroids. Exclusion criteria were being older than 2 years, receiving simultaneous other treatments, being lost to follow-up, or having insufficient information. Twenty-four original case series met inclusion criteria; 10 case series remained (184 patients) after exclusion criteria were applied. Intervention Patients were given a mean prednisone equivalent daily dose of 2.9 mg/kg (95% confidence interval [CI], 2.7-3.1 mg/kg) for a mean of 1.8 months (95% CI, 1.5-2.2 months). Main Outcome Measures Response and rebound rates and dose-response and adverse effects–response relationships in responders vs nonresponders. Results Response was 84% (95% CI, 78%-89%; range, 60%-100%) and rebound was 36% (95% CI, 29%-44%; range, 0%-65%). A significant difference was found between the mean dose administered to responders vs nonresponders ( P P = .3). Conclusion Systemic corticosteroid treatment seems to be effective for problematic cutaneous hemangiomas of infancy.
Laser Spark Ignition of a Blended Hydrogen-Natural Gas Fueled Single Cylinder Engine

Charge dilution, due to the reduced combustion temperatures that it brings about, has long been proven as effective means of reducing Nitrogen Oxides (NOx ) emissions in reciprocating engines. The extent of this dilution is practically bounded on the lean side of stoichiometric conditions by engine misfire or the point at which the combustion process is no longer sufficiently reliable to sustain engine operation within some specified limit. Extending this misfire limit of an engine becomes a worth while goal as it brings about further reductions in NOx emissions. Much work has been dedicated to reaching this end and several techniques have proven viable in natural gas fueled engines. This work explores potential synergies between two proven techniques for NOx reductions in lean-burn natural gas fueled engines, hydrogen enrichment of the natural gas fuel and application of laser spark ignition. Independently both techniques have been shown to provide significant NOx emissions reductions through lean limit extension in spark ignited gaseous fueled reciprocating engines [1–11, 13–15]. Here hydrogen is blended with natural gas at five different levels ranging from 0% to 40% by volume in a single cylinder engine. The mixtures are fired using a conventional spark plug based ignition system and then again with an open beam path laser induced breakdown spark ignition system. NOx emissions measurements were made at different levels including misfire conditions for each level of hydrogen enrichment with both ignition systems. Data are presented and the emissions and engine performance of two configurations are compared to determine realizable benefits that arise from combining the two techniques.Copyright © 2006 by ASME
Water-Assisted Tetragonal-to-Monoclinic Phase Transformation of ZrO2 at Low Temperatures

In-situ Raman spectroscopy has been used to characterize the transformation of amorphous zirconium oxyhydroxide to tetragonal ZrO2 and then to monoclinic ZrO2 in both the absence and presence of water vapor. In the absence of H2O vapor, t-ZrO2 forms when zirconium oxyhydroxide is treated in air above 673 K and the tetragonal-to-monoclinic transformation occurs at temperatures above 950 K. Treatment at progressively higher temperatures is accompanied by loss of surface area. The tetragonal-to-monoclinic transformation occurs when the size of the zirconia particles is equal to or greater than a critical size determined from an analysis of the thermodynamic stability of small particles of t- and m-ZrO2. Exposure of t-ZrO2 to 3 kPa of H2O or immersion in liquid water at 298 K results in its extensive (∼80%) transformation to m-ZrO2 without a loss in surface area. This observation is attributed to a decrease in the difference between the surface free energy of m-ZrO2 and that of t-ZrO2 caused by the adsorption...
Platinum-Catalyzed Phenyl and Methyl Group Transfer from Tin to Iridium : Evidence for an Autocatalytic Reaction Pathway with an Unusual Preference for Methyl Transfer

Platinum complexes have been found to catalyze the transfer of σ-bound ligands to the Ir center in Cp*(PMe3)IrCl2 (Cp* = η5-C5Me5) from Bu3SnPh and PhxSnMe4-x (x = 0−3) complexes. Despite the presence of Sn−Ph bonds in the PhxSnMe4-x complexes, exclusive transfer of the Sn−Me group occurs, an unusual chemoselective process. Examination of the reaction mechanism supports an autocatalytic process.
Thermodynamic Mapping of the Inhibitor Site of the Aspartic Protease Endothiapepsin

The discovery that the protease from the human immunodeficiency virus (HIV) belongs to the aspartic protease family has generated renewed interest in this class of proteins. In this paper, the interactions of endothiapepsin, an aspartic proteinase from the fungus Endothia parasitica, with the inhibitor pepstatin A have been studied by high-sensitivity calorimetric techniques. These experiments have permitted a complete characterization of the temperature and pH-dependence of the binding energetics. The binding reaction is characterized by negative intrinsic binding enthalpy and negative heat capacity changes. The association constant is maximal at low pH (2 x 10(9) M-1 at pH 3) but decreases upon increasing pH (8.1 x 10(6) M-1 at pH 7). The binding of the inhibitor is coupled to the protonation of one of the aspartic moieties in the Asp dyad of the catalytic site of the protein. This phenomenon is responsible for the decrease in the apparent affinity of the inhibitor for the enzyme upon increasing pH. The experimental results presented here indicate that the binding of the inhibitor is favored both enthalpically and entropically. While the favorable enthalpic contribution is intuitively expected, the favorable entropic contribution is due to the large gain in solvent-related entropy associated with the burial of a large hydrophobic surface, that overcompensates the loss in conformational and translational/rotational degrees of freedom upon complex formation. The characteristics of the molecular recognition process have been evaluated by means of structure-based thermodynamic analysis. Three regions in the protein contribute significantly to the free energy of binding: the residues surrounding the Asp dyad (Asp32 in the N-terminal lobe and Asp215 in the C-terminal domain) and the flap region (Ile73 to Asp77). In addition, the rearrangement of residues that are not in immediate contact with the inhibitor provides close to 40% of the protease contribution to the binding free energy. On the other hand, the two statine residues provide more than half of the inhibitor contributions to the total free energy of binding. It is demonstrated that a previously developed empirical structural parametrization of the thermodynamic parameters that define the Gibbs energy, accurately accounts for the binding energetics and its temperature and pH-dependence.
Relationship between the amount and equivocality of information processed and receptivity to change in information systems

Abstract Although a great deal has been written regarding various aspects of change in different contexts, the concept of relating the information requirements for task performance to individual receptiveness to change in the system that processes and provides the task-related information has not been addressed. This paper reports the results of a field study into these relationships. Individuals perceiving themselves as being required to process information with relatively greater equivocality were found to have more positive intentions regarding behaviours supportive of new computerized information systems. Also, a positive relationships was found between the amount of information processed and behavioural intentions regarding the system change.
HUMAN PAPILLOMAVIRUS E7 ONCOPROTEINS BIND A SINGLE FORM OF CYCLIN E IN A COMPLEX WITH CDK2 AND P107

Abstract The E6 and E7 proteins of the high-risk human papillomaviruses (HPVs) act coordinately to immortalize human keratinocytes. These viral oncoproteins function by binding and altering the activity of cellular proteins which regulate cell cycle progression. Among the proteins bound by E7 are the retinoblastoma protein, Rb, as well as the related p107 and p130 proteins. In addition, E7 binds cyclin A, which regulates transit through the S and G2/M phases of the cell cycle. In this study, we demonstrate that HPV 18 E7 also associates with cyclin E which controls the G1/S transition. E7/cyclin E complexes were immunoprecipitated from E7-expressing cells as well as from cell extracts using GST–E7 fusion proteins. E7 was found to complex with a single form of cyclin E, and the binding was mediated through p107. Both E7/cyclin E and E7/cyclin A complexes exhibit kinase activity through associated cdk2 proteins which can contribute to phosphorylation of p107. The association of E7 with proteins which regulate transit through the cell cycle may provide an additional mechanism by which infection with human papillomaviruses results in cellular hyperproliferation.
An emerging market credit scoring system for corporate bonds

Abstract In this article we introduce a scoring system (EMS Model) for Emerging Corporate Bonds. The scoring system provides an empirically based tool for the investor to use in making relative value determinations. The EMS Model is an enhanced version of the statistically proven Z-Score model. Unlike the original Z-Score model, our approach can be applied to nonmanufacturing companies, and manufacturers, and is relevant for privately held and publicly owned firms.The adjusted EMS Model incorporates the particular credit characteristics of emerging markets companies, and is best suited for assessing relative value among emerging markets credits. The model combines fundamental credit analysis and rigorous benchmarks together with analyst-enhanced assessments to reach a modified rating, which can then be compared to agency ratings (if any) and market levels. We have included a summary of Mexican companies for which we have applied the EMS Model. We have included in this a description of Mexican company credits, first from prior to the Mexican crisis (1994) then followed, in some cases, to a more recent date.
Comparative 35S‐sulfate and 3H‐proline metabolism within the interdental septal bone and adjacent periodontal ligament

Tooth movements require rapid remodeling of the periodontal ligament (PDL) and adjacent alveolar bone. Our objective was to compare the regional metabolism of sulfated-glycosaminoglycans (sGAG) within the PDL and adjacent alveolar bone and compare it to the metabolism of collagenous proteins using radioautographic techniques. Rats were injected with either 3H-proline or 35S-sulfate and maxillae were removed at 1, 6, and 12 hr 1–7 days later. Silver grains were counted over the PDL and adjacent alveolar bone and the incorporation and removal rates for each radioisotope were determined. In general, net collagenous protein incorporation and removal were greatest within the distal and net sGAG incorporation and removal were greatest within the mesial compartments of the periodontium. The rate of removal of 3H-proline was significantly greater within the distal alveolar bone surface than the adjacent PDL at all levels (P < 0.001). In contrast, the rate of removal of 35S-sulfate was significantly greater in the PDL than within the adjacent mesial surface of the interdental septum at all levels (P < 0.001). The mesial surfaces of the interdental septum had a slower rate of removal of both isotopes than distal surfaces at all levels (P < 0.001). Our data suggest significant regional differences in the metabolism of 35S-sulfate and 3H-proline within the PDL and alveolar bone, which likely result from the characteristics of the forces produced by the adjacent teeth and may be a factor in the remodeling of the alveolar wall coincident to tooth movement. Anat Rec Part A, 288A:817–826, 2006. © 2006 Wiley-Liss, Inc.
Measurement of the Hanle Effect for the OH Radical

We have used the coincidence of the Zn I 3072.06 \AA{} line with the ${R}_{12}(1)$ line of the (0, 0) band in the OH $A^{2}\ensuremath{\Sigma}^{+}\ensuremath{-}X^{2}\ensuremath{\Pi}$ ultraviolet system to perform a measurement of the molecular Hanle effect on the ${K}^{\ensuremath{'}}=2$, ${J}^{\ensuremath{'}}=\frac{3}{2}$ rotational level of the excited state. The OH was formed by the reaction H + N${\mathrm{O}}_{2}$ \ensuremath{\rightarrow} OH + NO, and the Hanle linewidth is extrapolated to zero pressure of ${\mathrm{H}}_{2}$ and N${\mathrm{O}}_{2}$. The half-width is found to be 258 \ifmmode\pm\else\textpm\fi{} 36 mG and the pressure broadening of the linewidth corresponds to 13 \ifmmode\pm\else\textpm\fi{} 7 mG/m Torr of N${\mathrm{O}}_{2}$ pressure and 5.2 \ifmmode\pm\else\textpm\fi{} 0.8 mG/m Torr of ${\mathrm{H}}_{2}$ pressure. This linewidth gives a value of $g\ensuremath{\tau}=(2.20\ifmmode\pm\else\textpm\fi{}0.27)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}$ sec for this excited state of the OH molecule.
Analysis of protonated and alkali metal cationized aminoglycoside antibiotics by collision-activated dissociation and infrared multi-photon dissociation in the quadrupole ion trap.

Nine aminoglycoside antibiotics were analyzed in two quadrupole ion trap mass spectrometers using electrospray ionization. Structural information was obtained via collision-activated dissociation (CAD) and infrared multi-photon dissociation (IRMPD) of the protonated species. Several of the compounds, having multiple basic sites, preferred the doubly protonated form while some existed in the singly charged state or were distributed between single and doubly protonated species, allowing comparison of the fragmentation patterns of the two charge states. In general, IRMPD is as efficient as CAD, produces more low-mass fragment ions, and is more universally applied owing to its low dependence on trapping, pressure and tuning conditions. Alkali metal complexation using Li+ and Na+ was probed as a means of producing different fragmentation patterns, but in most cases the resulting fragmentation patterns were simplified versions of those obtained for the protonated analogs. Copyright © 2000 John Wiley & Sons, Ltd.
Association of Short-Strand DNA Oligomers with Guanidinium-Linked Nucleosides. A Kinetic and Thermodynamic Study

Complementary short-strand DNA homooligomers and guanidinium-linked homonucleosides associate and form triplexes in solution. The melting temperatures, Tm, the association and dissociation kinetic and thermodynamic parameters, and activation energies were determined by UV thermal analysis for the triplexes of short strand DNA homooligomers {d(pA)5-d(pA)12-18} and poly(dA) with the guanidinium-linked nucleoside d(Tg)4-T-azido {DNG5}. The melting and cooling curves exhibit hysteresis behavior in the temperature range of 5−95 °C at 0.2 deg/min thermal rate. From these curves the rate constants and the energies of activation for association (kon, Eon) and dissociation (koff, Eoff) processes were obtained. The Tm decreases with the ionic strength and increases slightly with increase in concentration of the monomers. A greater increase in the Tm results from an increase in the length of the DNA strand d(pA)x. In the case of d(pA)5 and d(pA)6, triplexes are formed, with Tm = 34 and 39 °C, respectively, only abov...
Tidal Constraints on the Masses of Extrasolar Planets

Tidal theory predicts that the orbits of close extrasolar giant planets will circularize on timescales that can be comparable to the ages of those systems. Additionally, planets that are close enough and massive enough can spin up their central stars. Since the eccentricities of extrasolar planet orbits are determined by the radial velocity technique and since stellar rotation rates are observed, or at least derived, limits on the masses of close extrasolar planets can be placed. We find upper limits on the masses of eight extrasolar planets, including limiting the masses of υ And b, HD 75289b, HD 187123b, and 51 Peg b to less than 1.48, 1.21, 0.59, and 0.51 Jupiter masses, respectively. There is a contradiction in the constrained mass of HD 217107b, in that its eccentricity is apparently too high. This anomalously high eccentricity could be real and caused by other planets in that system; or it could be an artifact of fitting a one-orbit solution to multiplanet data. The tidal limits placed on all these extrasolar planets are only as good as the knowledge of the stellar parameters (age, rotation period), which in some cases is not very good; better detailed knowledge of stars hosting planets will be necessary.
The Relations of Stuttering to Word Length and Word Frequency

Twenty stutterers recorded nine 10-word lists in the presence of a single listener. The word lists were composed of combinations of three levels of word length and three levels of word frequency. A...
Effect of Tranquillizing Drugs during Pregnancy on Activity of Offspring

INJECTION of certain tranquillizing drugs during pregnancy produces defects in maze learning1, defects in both the acquisition and extinction of a conditioned avoidance response2, and lower weight1,2 in the offspring of the injected animals. These effects vary according to the period of administration, as well as the drug involved3. All the tranquillizing drugs which were used had some adverse effect, but this was not uniform. In this communication we describe attempts to extend the scope of previous work on the effects of these drugs on activity, emotionality and reaction to stress (ulceration).
Physical Properties of Sand as Affected by Clinoptilolite Zeolite Particle Size and Quantity

Little is known about how the particle size of amendments influences the physical properties of amendment-sand mixtures. In two laboratory experiments, the amendment clinoptilolite zeolite (CZ) was used to amend sand at two sand:CZ ratios of 5 and 10 (w/w) and six CZ particle sizes, including: >1 mm, 1 to 0.5 mm, 0.5 to 0.25 mm, 0.25 to 0.105 mm, 0.105 to 0.047 mm and <0.047 mm. Saturated hydraulic conductivity (SHC) ranged from 3 to 48 cm hr¯¹, decreased with the decreasing CZ particle size which was most noticeable at the finest CZ particle size. The water content of CZ-sand mixtures at soil matric potentials from -3 kPa to - 10 kPa increased with decreasing CZ particle size. Bulk density of the CZ-sand mixtures (except for CZ-mixtures < 0.047 mm) ranged from 1.37 to 1.42 g cm¯³, which were significantly (p = 0.01) lowered than the unamended sand (1.48 g cm¯³) . Sand amended with 10% of the finest CZ particle size had the lowest total porosity (41.5 g Kg¯²). Aeration porosity (at -3 kPa soil matric pote...
Understanding Production Systems through Human Simulation: Experiencing JIC (Just‐in‐case) JIT (Just‐in‐time) and OPT (Optimised‐Production‐Technology) Production Systems

Teaching students basic differences among various production systems, such as the American JIC (Just‐in‐case) system, the Japanese JIT (Just‐in‐time) system and the latest OPT (Optimised‐Production‐Technology) system, is not a simple task. Students can be taught basic principles, but whether they truly understand and appreciate what makes one technique superior to another is questionable. After considerable experience in teaching JIC, JIT and OPT, and because of the above concerns, this author has designed a human simulation, called the Production Walk Games. Through these production walks, students not only learn, but also experience, three production methods. The production techniques are briefly discussed and how they are simulated for the students through their production walk games is explained. Two sets of results of these walks are presented and briefly analysed.
Unmarried Boomers Confront Old Age: A National Portrait

Purpose of the Study: Our study provides a national portrait of the Baby Boom generation, paying particular attention to the heterogeneity among unmarried Boomers and whether it operates similarly among women versus men. Design and Methods: We used the 1980, 1990, and 2000 Census 5% samples and the 2009 American Community Survey (ACS) to document the trends in the share and marital status composition of the unmarried population during midlife. Using the 2009 ACS, we developed a sociodemographic portrait of Baby Boomers according to marital status. Results: One in three Baby Boomers was unmarried. The vast majority of these unmarried Boomers were either divorced or nevermarried; just 10% were widowed. Unmarried Boomers faced greater economic, health, and social vulnerabilities compared to married Boomers. Divorced Boomers had more economic resources and better health than widowed and never-married Boomers. Widows appeared to be the most disadvantaged among Boomer women, whereas nevermarrieds were the least advantaged among Boomer men. Implications: The rise in unmarrieds at midlife leaves Baby Boomers vulnerable to the vagaries of aging. Health care and social service providers as well as policy makers must recognize the various risk profiles of different unmarried Boomers to ensure
SARDSRN: A Neural Network Shift-Reduce Parser

Simple Recurrent Networks (SRNs) have been widely used in natural language tasks. SARDSRN extends the SRN by explicitly representing the input sequence in a SARDNET self-organizing map. The distributed SRN component leads to good generalization and robust cognitive properties, whereas the SARDNET map provides exact representations of the sentence constituents. This combination allows SARDSRN to learn to parse sentences with more complicated structure than can the SRN alone, and suggests that the approach could scale up to realistic natural language.
International players from Asia: an analysis of text themes in news coverage.

This study examined current trends in news topics and text themes of news coverage in the USA and Taiwan about international players from Asia. Content analysis was used to evaluate news coverage for this study. Ninety-five sampling articles were chosen from the database in the USA while 272 articles were chosen from Taiwan. The results indicated that the media in the USA covered more news stories about international sport marketing than did Taiwan. The results of this study show a win-win situation for the teams in the US and a player's native country. Names of stadiums, league, teams, players and players from Asia are frequently covered in the news articles, which increases readers' and fans' knowledge and name recognition of teams.