cssi/SciSciGPT-SciSciNet huggingface dataset:
Observation of the shadows of the Moon and Sun using 100 TeV cosmic rays

The Chicago Air Shower Array has imaged the shadows of the Moon and Sun and measured the angular diameter of the Moon with cosmic rays having energies above about 100 TeV. The shadow of the Sun shows effects attributed to the curvature of cosmic rays by the solar magnetic field. This study verifies that our direction reconstruction has no serious systematic errors, and provides a measure of the angular resolution of the array.
SU-E-T-603: Influence of PTV Delineation at Air Cavity Interface on Tomotherapy Plan Quality.

Purpose: To determine if different ways in PTV delineation at an air cavity interface yield differences in overall plan quality and treatment efficiency Methods: Three different PTVs were used for treating a patient whose CTV surrounded a large air cavity created by a resected hard palate. The CTV lined the surface of the air cavity while PTV1 included the entire air cavity, PTV2 extended 4mm from the surface of the cavity into air, and PTV3 was reduced 4mm within the surface of the cavity. Tomotherapy plans were generated for all three PTVs. During each planning, all constraints to target and normal structures were kept constant along with the number of optimizations. Same planning process was repeated on a head and neck digital phantom with mock target, normal structures and cavity.Results: Three treatment planning approaches showed no significantly different target coverage in terms of minimum or maximum dose to their respective PTVs. All plans attained 95% coverage of the CTV and PTV by 100% of the prescription. The conformity index (CI) of the plans delivered to PTV1, PTV2, and PTV3 were 1.09, 1.11, and 1.18, respectively. The skin, optic nerves, brainstem and spinal cord all received similar maximum dose to their respective volumes for each plan within 1Gy. The monitor units required for each treatment plan were all within 6% of one another with PTV1 having the highest. For head and neck phantom, the CIs of three plans were 1.05, 1.21, and 1.18, respectively. The coverage of the phantom CTV and sparing of normal structures were nearly equivalent. The total treatment times were identical. Conclusions: Tomotherapy planning is able to deliver dose to a head and neck PTV containing a large air cavity without compromising target coverage, sparing of normal tissues, or delivery time.
The Reaction between Tetra-tert-butoxytin and Al(110)−OH in Ultrahigh Vacuum: Contrasting Behavior vs Its Zirconium Analogue

The organometallic chemical vapor deposition reaction between tetra-tert-butoxytin and hydroxylated Al(110) proceeds in ultrahigh vacuum to generate a surface-bound tin alkoxide product. The stoichiometry of the product, [Al]-[O] 3 -Sn(OBu t ), is different from that observed for zirconium alkoxide analogues. Facile ligand exchange oftert-butoxy for phenoxy can be accomplished for the surface-bound tin complex. Heating either surface tert-butoxytin or phenoxytin species ultimately gives the zerovalent metal. Deposition and thermal evolution reactions were followed by both reflection-absorption infrared and X-ray photoelectron spectroscopies.
Adrenoleukodystrophy and related disorders.

Keywords: adrenoleukodystrophy; X-linked; very long chain fatty acids; phytanic acid; peroxisomes
A modification of the Lowry procedure to simplify protein determination in membrane and lipoprotein samples

Abstract The original Lowry method of protein determination has been modified by the addition of sodium dodecyl sulfate in the alkali reagent and an increase in the amount of copper tartrate reagent. These alterations allowed the method to be used with membrane and lipoprotein preparations without prior solubilization or lipid extraction and with samples containing 200 m m sucrose or 2.5 m m EDTA.
The origin of threhalose and its significance during the formation of encysted dormant embryos of Artmia salina

1. 1. A study has been made of trehalose and other carbohydrates in Artemia salina embryos of two types: one which enters dormancy as a blastula and one which undergoes direct development. 2. 2. After 10 hr of development the presumptive dormant embryo contains at least eight times and amount of trehalose present in the non-dormant embryo. When the blastula enters dormanyc trehalose constitutes about 15 per cent of the dry weight, whereas non-dormant embryos of comparable age have essentially no trehalose. 3. 3. Analyses of female hemolymph and studies on presumptive dormant embryos in vitro show that trehalose is snythesized by the developing embryos. 4. 4. The glycogen levels of both types of embryos are similar after 10 hr of development. During subsequent development of the presumptive dormant embryo the glycogen content decreases markedly, but it remains at a high level in the non-dormant embryo. 5. 5. Presumptive dormant embryos contain about twice the amount of glycerol present in non-dormant embryos after 10 hr of development, and this relationship remains about the same with further development. 6. 6. The significance of trehalose accumulation in Artemia embryos is discussed.
Cyclopoid copepods associated with marine invertebrates in Mauritius

Three species of Sabelliphilidae and four species of Lichomolgidae are reported as associates of scleractinian corals, nudibranchs, polychaetes, asteroids, and holothurians in Mauritius. A sabelliphilid from the polychaete Sabellastarte magnifica represents a new genus and species. Two previously described lichomolgids are recorded from new hosts. Species ranges are extended from Madagascar and New Caledonia to Mauritius.
SOLVING A NONLINEAR BILEVEL PROGRAMMING MODEL OF THE EQUILIBRIUM NETWORK DESIGN PROBLEM FOR KOREA

A network design problem solves for link improvements or additions to an existing transportation network provided that a certain objective function such as social welfare is maximised. In addition, an equilibrium network design problem specifically requires each link to have user equilibrium flows.
Purine inhibition of [3H]-γ-aminobutyric acid receptor binding to rat brain membranes

Abstract Several purines, including inosine and hypoxanthine, inhibit the binding of [ 3H ]-γ-amino-butyric acid (GABA) and [ 3H ]diazepam to freeze-thawed and extensively washed rat brain membranes. While purines have been reported to inhibit diazepam binding competitively, their interactions with GABA receptors in both mitochondrial and mitochondrial plus microsomal fractions are noncompetitive. The possibility that purines may bind at one site and affect the GABA receptor-ionophore-benzodi-azepine complex is discussed.
Use of comparative proteomics to identify potential resistance mechanisms in cancer treatment

Drug resistance is a major problem in successful cancer chemotherapy. Many molecular mechanisms that are responsible for drug resistance are known whereas others have yet to be discovered. Determining the exact mechanism activated in a particular case (clinical or laboratory) is a difficult task. Recently, proteomics has been applied to investigate drug resistance mechanisms in model cancer cell lines. As a result, novel mechanisms of resistance have been discovered and known mechanisms of resistance confirmed. In this paper, we wish to review recent developments and progresses in the application of proteomic tools to identify known and novel drug resistance mechanisms in drug-selected model cancer cell lines. Our combined analyses of multiple proteomic studies of various drug resistant cancer cell lines revealed that many mechanisms of resistance likely exist in any given drug-selected cancer cell line and that common mechanisms of resistance may be selected in a spectrum of cancer cell lines. These observations suggest that combination therapies targeting multiple mechanisms to sensitize drug resistant cancers may be necessary to eradicate cancers in the future.
Suppression of Detrusor-Sphincter Dyssynergia by Immunoneutralization of Nerve Growth Factor in Lumbosacral Spinal Cord in Spinal Cord Injured Rats

ABSTRACTPurpose: We investigated the effects of intrathecal application of nerve growth factor (NGF) antibodies (NGF-Abs) and desensitization of C-fiber afferent pathways by capsaicin treatment on detrusor-sphincter dyssynergia (DSD) after spinal cord injury (SCI).Materials and Methods: In adult female rats SCI was induced by complete transection of the spinal cord at Th8 to 9. Ten days after spinalization vehicle or NGF-Ab (10 μg daily) was continuously administered at the level of the L6-S1 spinal cord through an implanted intrathecal catheter connected to an osmotic pump for 2 weeks. Another group of spinalized rats was treated with capsaicin (125 mg/kg subcutaneously) 3 weeks after spinalization and 5 days before experiments. Simultaneous recordings of intravesical pressure and urethral perfusion pressure were then performed. NGF levels in the L6 spinal cord were measured in vehicle or NGF-Ab treated spinalized rats using enzyme-linked immunosorbent assay.Results: DSD was observed in all vehicle treat...
Two-dimensional visualization of ignition kernels in an IC engine☆

Abstract Ignition kernels in a ported premixed-charge spark-ignition engine were examined using 2-dimensional visualization. A pulsed laser sheet was passed through the engine and the Mie scattering by the TiO 2 seeding particles was collected by a 100 × 100 pixel diode array with a field of view of 1 cm × 1 cm, and then digitized. The engine used a stoichiometric propaneair mixture and was operated at 300, 1200, and 3000 rpm. It is concluded that the turbulent flow field affected all the kernels examined, which included kernels as small as 2 mm and times after ignition as short as 100 μs. Increasing distortion and cycle-to-cycle variations in the ignition kernel with increasing engine speed were noted. Locally the flame front is often no thicker than the 200 μm resolution limit of the system. This implies that the turbulent flames are in the reaction sheet regime.
Inhibition of microglial P2X4 receptors attenuates morphine tolerance, Iba1, GFAP and μ opioid receptor protein expression while enhancing perivascular microglial ED2

Anti-nociceptive tolerance to opioids is a well-described phenomenon, which severely limits the clinical efficacy of opioids for the treatment of chronic pain syndromes. The mechanisms that drive anti-nociceptive tolerance, however, are less well understood. We have previously shown that glia have a central role in the development of morphine tolerance and that administration of a glial modulating agent attenuated tolerance formation. Recently, we have demonstrated that morphine enhances microglial Iba1 expression and P2X4 receptor-mediated microglial migration via direct mu opioid receptor signaling in in vitro microglial cultures. We hypothesize that P2X4 receptors drive morphine tolerance and modulate morphine-induced spinal glial reactivity. Additionally, we hypothesize that perivascular microglia play a role in morphine tolerance and that P2X4 receptor expression regulates perivascular microglia ED2 expression. To test these hypotheses, rats were implanted with osmotic minipumps releasing morphine or saline subcutaneously for seven days. Beginning three days prior to morphine treatment, P2X4 receptor antisense oligonucleotide (asODN) was injected intrathecally daily, to selectively inhibit P2X4 receptor expression. P2X4 receptor asODN treatment inhibited morphine-induced P2X4 receptor expression and blocked anti-nociceptive tolerance to systemically administered morphine. P2X4 receptor asODN treatment also attenuated the morphine-dependent increase of spinal ionized calcium binding protein (Iba1), glial fibrillary acidic protein (GFAP) and mu opioid receptor protein expression. Chronic morphine also decreased perivascular microglial ED2 expression, which was reversed by P2X4 receptor asODN. Together, these data suggest that the modulation of P2X4 receptor expression on microglia and perivascular microglia may prove an attractive target for adjuvant therapy to attenuate opioid-induced anti-nociceptive tolerance.
Reinforcing and phencyclidine-like stimulus properties of enantiomers of metazocine.

Abstract The positive reinforcing properties of the racemate and stereoisomers of the benzomorphan, metazocine, were tested in three rhesus monkeys trained to self-administer IV injections of cocaine. The (−)-isomer maintained responding above saline levels at the highest dose tested (30 μg/kg/injection) in two of the three monkeys. Likewise, (+)-metazocine maintained self-administration responding in two monkeys at a dose of 100 μg/kg/injection. Responding for (±)-metazocine was maintained in all three monkeys at doses of 10–100 μg/kg/injection. The discriminative stimulus properties of the three forms of metazocine were tested in rats trained to discriminate phencyclidine (PCP; 3.0 mg/kg) from saline on a two-lever food-reinforced operant task. When metazocine was tested in these animals, only the (+)-isomer produced dose-related increases in responding on the PCP-lever. Both (+)- and (−)-metazocine resulted in only saline-appropriate responding. Thus, the results of these two experiments demonstrate that both enantiomers of metazocine function as positive reinforcers in monkeys and further, the reinforcing properties of (+)-metazocine may be due to the PCP/sigma properties of this isomer.
Thioredoxin Reductase 1 Expression and Castration-recurrent Growth of Prostate Cancer

INTRODUCTION: Many genes are differentially expressed between androgen-dependent and androgen-independent prostate cancer (CaP). Differential expression analysis and subtractive hybridization previously identified nine genes expressed in intact mice bearing CWR22 tumors and castrated mice bearing recurrent CWR22 tumors but not in regressed tumors. The objectives of this study were to develop an immunostaining method to dual-label foci of proliferating tumor cells [the origin of castration-recurrent CaP (CR-CaP)], to determine which of the nine candidate proteins were differentially expressed in proliferating versus nonproliferating cells at the onset of growth after castration, and to test preclinical findings using clinical specimens of androgen-stimulated benign prostate (AS-BP) and CaP (AS-CaP) and CR-CaP. METHODS: Paraffin-embedded, bromodeoxyuridine-injected CWR22 tumors were hydrated, antigen-retrieved using high heat and high pressure, labeled for each of the nine antigens of interest, visualized using peroxidase, and counterstained with hematoxylin. Mean optical density was calculated for proliferating and nonproliferating areas using automated (nuclear staining) or manual (cytoplasmic staining) image analysis. Prostate tissue microarray sections were immunostained and visually scored. RESULTS: Immunohistochemistry revealed higher nuclear expression of thioredoxin reductase 1 (TrxR1) in proliferating cells than nonproliferating cells (P < .005). There were no statistical differences between cell types in the expression of other proteins. TrxR1 expression was higher (P < .01) in CR-CaP compared with AS-BP or AS-CaP. CONCLUSIONS: Increased TrxR1 expression in CR-CaP was consistent with increased TrxR1 and BrdU expression at the onset of growth in the CWR22 model. Thioredoxin reductase 1 should be targeted in an attempt to delay or prevent CaP recurrence after castration.
ON-AXIS COHERENT OPTICAL FEEDBACK SYSTEM FOR IMAGE PROCESSING

Coherent optical feedback systems always use a pair of tilted mirrors that physically separate the forward path and the feedback path, one of which is at an off-axis position. This paper introduces an on-axis configuration with two parallel mirrors. The application of the system to contrast enhancement and image restoration is presented.© (1976) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A resequence analysis of genomic loci on chromosomes 1q32.1, 5p15.33, and 13q22.1 associated with pancreatic cancer risk.

Objective The objective of this study was to fine-map common pancreatic cancer susceptibility regions. Methods We conducted targeted Roche-454 resequencing across 428 kb in 3 genomic regions identified in genome-wide association studies (GWAS) of pancreatic cancer, on chromosomes 1q32.1, 5p15.33, and 13q22.1. Results An analytical pipeline for calling genotypes was developed using HapMap samples sequenced on chr5p15.33. Concordance to 1000 Genomes data for chr5p15.33 was greater than 96%. The concordance for chr1q32.1 and chr13q22.1 with pancreatic cancer GWAS data was greater than 99%. Between 9.2% and 19.0% of variants detected were not present in 1000 Genomes for the respective continental population. The majority of completely novel single-nucleotide polymorphisms (SNPs) were less common (minor allele frequency [MAF], ≤5%) or rare (MAF, ≤2%), illustrating the value of enlarging test sets for discovery of less common variants. Using the data set, we examined haplotype blocks across each region using a tag SNP analysis (r2 > 0.8 for MAF of ≥5%) and determined that at least 196, 243, and 63 SNPs are required for fine-mapping chr1q32.1, chr5p15.33, and chr13q22.1, respectively, in European populations. Conclusions We have characterized germline variation in 3 regions associated with pancreatic cancer risk and show that targeted resequencing leads to the discovery of novel variants and improves the completeness of germline sequence variants for fine-mapping GWAS susceptibility loci.
Amelogenin dosage compensation in carcinoma of colon, lung, liver and kidney, is not a marker of clonality in males

Abstract The analysis of patterns of X-chromosome inactivation is becoming increasingly utilized as a marker of clonal composition of tissues from women. To date, however, no analogous system has been found for the study of clonality in tissue from men. In the current study, the methylation patterns for portions of the amelogenin genes are tested, which are encoded on both the X- and Y-chromosome (AMGX and AMGY). The polymerase chain reaction (PCR) was used to amplify portions of AMGX and AMGY from genomic DNA of carcinomas of the colon, lung, liver and kidney, as well as from matched normal somatic tissues. The amplification target includedAlu Imethylation sensitive restriction endonuclease sites as well as a 189 bp sequence which is present in AMGX but is absent in AMGY. Polymerase chain reaction amplification of AMGX and AMGY was successful using genomic DNA from both tumour and normal control tissue in 24 of the 26 cases. Pretreatment of genomic DNA withAlu Iblocked amplification of AMGX in all cases from both normal tissue and tumour. This indicates that AMGX and AMGY undergo a non-random pattern of methylation in both normal tissues and in tumours, precluding their use as a marker of clonality. Methylation ofAlu Isites in AMGY suggests that the amelogenin genes undergo dosage compensation, which raises the possibility that the expression of amelogenin is not restricted to the development of the tooth bud but may also play some other role in various tissues of the body.
Olivine friction at the base of oceanic seismogenic zones

[1] We investigate the strength and frictional behavior of olivine aggregates at temperatures and effective confining pressures similar to those at the base of the seismogenic zone on a typical ridge transform fault. Triaxial compression tests were conducted on dry olivine powder (grain size ≤60 μm) at effective confining pressures between 50 and 300 MPa (using Argon as a pore fluid), temperatures between 600°C and 1000°C, and axial displacement rates from 0.06 to 60 μm/s (axial strain rates from 3 × 10−6 to 3 × 10−3 s−1). Yielding shows a negative pressure dependence, consistent with predictions for shear enhanced compaction and with the observation that samples exhibit compaction during the initial stages of the experiments. A combination of mechanical data and microstructural observations demonstrate that deformation was accommodated by frictional processes. Sample strengths were pressure-dependent and nearly independent of temperature. Localized shear zones formed in initially homogeneous aggregates early in the experiments. The frictional response to changes in loading rate is well described by rate and state constitutive laws, with a transition from velocity-weakening to velocity-strengthening at 1000°C. Microstructural observations and physical models indicate that plastic yielding of asperities at high temperatures and low axial strain rates stabilizes frictional sliding. Extrapolation of our experimental data to geologic strain rates indicates that a transition from velocity weakening to velocity strengthening occurs at approximately 600°C, consistent with the focal depths of earthquakes in the oceanic lithosphere.
Comparing the Effectiveness of Online Learning Approaches on CS1 Learning Outcomes

People are increasingly turning to online resources to learn to code. However, despite their prevalence, it is still unclear how successful these resources are at teaching CS1 programming concepts. Using a pretest-posttest study design, we measured the performance of 60 novices before and after they used one of the following, randomly assigned learning activities: 1) complete a Python course on a website called Codecademy, 2) play through and finish a debugging game called Gidget, or 3) use Gidget's puzzle designer to write programs from scratch. The pre- and post-test exams consisted of 24 multiple choice questions that were selected and validated based on data from 1,494 crowdsourced respondents. All 60 of our novices across the three conditions did poorly on the exams overall in both the pre-tests and post-tests (e.g., the best median post-test score was 50% correct). However, those completing the Codecademy course and those playing through the Gidget game showed over a 100% increase in correct answers when comparing their post-test exam scores to their pre-test exam scores. Those playing Gidget, however, achieved these same learning gains in half the time. This was in contrast to novices that used the puzzle designer, who did not show any measurable learning gains. All participants performed similarly within their own conditions, regardless of gender, age, or education. These findings suggest that discretionary online educational technologies can successfully teach novices introductory programming concepts (to a degree) within a few hours when explicitly guided by a curriculum.
A change of variables formula for stratonovich integrals and existence of solutions for two-point stochastic boundary value problems

Existence results for a class of two point non-adaptive stochastic boundary value problems are derived by combining a (new) change of variables formula with optimal control techniques. The class of equations treated is significantly wider than that for which previously known existence results apply.
Extended structural balance theory for modeling trust in social networks

Modeling trust in very large social networks is a hard problem due to the highly noisy nature of these networks that span trust relationships from many different contexts, based on judgments of reliability, dependability and competence and the relationships vary in their level of strength. In this paper, we introduce a new extended balance theory as a foundational theory of trust in networks. Our theory preserves the distinctions between trust and distrust as suggested in the literature, but also incorporates the notion of relationship strength which can be expressed as either discrete categorical values, as pairwise comparisons or as metric distances. Our model is novel, has sound social and psychological basis, and captures the classical balance theory as a special case. We then propose a convergence model, describing how an imbalanced network evolves towards new balance and formulate the convergence problem of a social network as a Metric Multidimensional Scaling (MDS) optimization problem. Finally, we show how the convergence model can be used to predict edge signs in social networks, and justify our theory through experiments on real datasets.
ω-Agatoxin IVA identifies a single calcium channel subtype which contributes to the potassium-induced release of acetylcholine, 5-hydroxytryptamine, dopamine, γ-aminobutyric acid and glutamate from rat brain slices

The voltage-dependent calcium channels (VDCCs) involved in K+-induced transmitter release have been studied. A maximally effective concentration of the N-type VDCC inhibitor, ω-conotoxin GVIA (GVIA) blocked the release of 5-HT (30%), DA (30%) and ACh (60%) but not that of GABA or glutamate. The O, P and Q-type VDCC inhibitor, ω-agatoxin IVA (Aga IVA, 1 μM), blocked 100% of GABA and glutamate, 70% of DA and about 50% of 5-HT and ACh release. The slopes of the inhibition curves indicate that it acts on the same, single type of VDCC in all cases. ω-Conotoxin MVIIC (MVIIC) completely inhibited the release of all the transmitters. It is concluded that a single GVIA-insensitive type of VDCC is involved in the K+-induced release of all the transmitters and, in addition, N-type VDCCs, with a higher affinity for GVIA than MVIIC, are required for the release of 5-HT, DA and ACh. The non-N-type VDCC is not the O-type as it is not blocked by low (< 10 nM) concentrations of MVIIC. Further resolution of this VDCC into P or Q-type requires more selective antagonists.
Linear Programming Models for Production-Advertising Decisions

This paper studies the problem of simultaneously smoothing production and inventory and setting advertising levels. The models given are linear programming models, assuming a deterministic demand-advertising-price relationship. The formulations include both one period and multiperiod models. Advertising has a decreasing effect within each period with a saturation level of advertising included and advertising also has a decreasing effect through time, allowing a build up of a stock of goodwill. A decomposition approach is given which is very efficient computationally due to the simplicity of the subproblems. Other computational aids are discussed; the pricing problem is examined briefly; and a numerical example is given to indicate the possible effect of considering production and advertising and pricing decisions together.
Understanding semantic relationships

To develop sophisticated database management systems, there is a need to incorporate more understanding of the real world in the information that is stored in a database. Semantic data models have been developed to try to capture some of the meaning, as well as the structure, of data using abstractions such as inclusion, aggregation, and association. Besides these well-known relationships, a number of additional semantic relationships have been identified by researchers in other disciplines such as linguistics, logic, and cognitive psychology. This article explores some of the lesser-recognized semantic relationships and discusses both how they could be captured, either manually or by using an automated tool, and their impact on database design. To demonstrate the feasibility of this research, a prototype system for analyzing semantic relationships, called the Semantic Relationship Analyzer, is presented.
Magnetoresistance of One-Dimensional Subbands in Tunnel-Coupled Double Quantum Wires

We study the low-temperature in-plane magnetoresistance of tunnel-coupled quasi-one-dimensional quantum wires. The wires are defined by two pairs of mutually aligned split gates on opposite sides of a < 1 micron thick AlGaAs/GaAs double quantum well heterostructure, allowing independent control of their widths. In the ballistic regime, when both wires are defined and the field is perpendicular to the current, a large resistance peak at ~6 Tesla is observed with a strong gate voltage dependence. The data is consistent with a counting model whereby the number of subbands crossing the Fermi level changes with field due to the formation of an anticrossing in each pair of 1D subbands.
Nonuniform Codes for Correcting Asymmetric Errors in Data Storage

The construction of asymmetric error-correcting codes is a topic that was studied extensively, however; the existing approach for code construction assumes that every codeword should tolerate t asymmetric errors. Our main observation is that in contrast to symmetric errors, asymmetric errors are content dependent. For example, in Z-channels, the all-1 codeword is prone to have more errors than the all-0 codeword. This motivates us to develop nonuniform codes whose codewords can tolerate different numbers of asymmetric errors depending on their Hamming weights. The idea in a nonuniform codes' construction is to augment the redundancy in a content-dependent way and guarantee the worst case reliability while maximizing the code size. In this paper, we first study nonuniform codes for Z-channels, namely, they only suffer one type of errors, say 1→ 0. Specifically, we derive their upper bounds, analyze their asymptotic performances, and introduce two general constructions. Then, we extend the concept and results of nonuniform codes to general binary asymmetric channels, where the error probability for each bit from 0 to 1 is smaller than that from 1 to 0.
Biochemical properties of the Cdc42-associated tyrosine kinase ACK1: Substrate specificity, autophosphorylation, and interaction with Hck

ACK1 (activated Cdc42-associated kinase 1) is a nonreceptor tyrosine kinase and the only tyrosine kinase known to interact with Cdc42. To characterize the enzymatic properties of ACK, we have expressed and purified active ACK using the baculovirus/Sf9 cell system. This ACK1 construct contains (from N to C terminus) the kinase catalytic domain, SH3 domain, and Cdc42-binding Cdc42/Rac interactive binding (CRIB) domain. We characterized the substrate specificity of ACK1 using synthetic peptides, and we show that the specificity of the ACK1 catalytic domain most closely resembles that of Abl. Purified ACK1 undergoes autophosphorylation, and autophosphorylation enhances kinase activity. We identified Tyr284 in the activation loop of ACK1 as the primary autophosphorylation site using mass spectrometry. When expressed in COS-7 cells, the Y284F mutant ACK1 showed dramatically reduced levels of tyrosine phosphorylation. Although the SH3 and CRIB domains of purified ACK1 are able to bind ligands (a polyproline peptide and Cdc42, respectively), the addition of ligands did not stimulate tyrosine kinase activity. To characterize potential interacting partners for ACK1, we screened several SH2 and SH3 domains for their ability to bind to full-length ACK1 or to the catalytic-SH3-CRIB construct. ACK1 interacts most strongly with the SH3 domains of Src family kinases (Src or Hck) via its C-terminal proline-rich domain. Co-expression of Hck with kinase-inactive ACK1(K158R) in mammalian cells resulted in tyrosine phosphorylation of ACK1, suggesting that ACK1 is a substrate for Hck. Our data suggest that Hck is a novel binding partner for ACK1 that can regulate ACK1 activity by phosphorylation.
Microstructural Simulation of Asphalt Materials: Modeling and Experimental Studies

Asphalt concrete is a heterogeneous material composed of aggregates, binder cement, and air voids, and may be described as a cemented particulate system. The load carrying behavior of such a material is strongly related to the local load transfer between aggregate particles, and this is taken as the microstructural response. Simulation of this material behavior was accomplished using a finite element technique, which was constructed to simulate the micromechanical response of the aggregate/binder system. The model incor- porated a network of special frame elements with a stiffness matrix developed to predict the load transfer between cemented particles. The stiffness matrix was created from an approximate elasticity solution of the stress and displacement field in a cementation layer between particle pairs. A damage mechanics approach was then incorporated with this solution, and this lead to the construction of a softening model capable of predicting typical global inelastic behaviors found in asphalt materials. This theory was then implemented within the ABAQUS finite element analysis code to conduct simulations of particular laboratory specimens. Experimental verification of the elastic response has included tests on specially prepared cemented particulate systems, which allowed detailed measurement of aggregate displacements and rotations using video imaging and computer analysis. Model simulations compared favorably with these experimental results. Additional simulations including inelastic behavior of laboratory indirect tension tests have been conducted, and while preliminary in nature these results also compared well with experimental data.
John Davis and the meanings of licking.

This paper reviews the contribution of John Davis to understanding how meal size is organized and controlled in the rat. By measuring the rate and pattern of licking of various liquid diets during sham feeding and real feeding, Davis demonstrated that meal size is the result of the central integration of positive feedback from orosensory stimulation and negative feedback from postingestive stimulation of the stomach and small intestine. The potency of these feedbacks is modulated by a variety of factors including experience and deprivation. At the microstructural level, orosensory stimulation increases burst size or cluster size, while postingestive negative feedback decreases the number of bursts or clusters. His results remind us that behavior is the basic science of ingestion, important in itself, and essential for the investigation of the neural mechanisms that organize it.
Novel agents for colorectal cancer.

The compound 5-fluorouracil (5-FU) has been investigated for over four decades; research has focussed on examining various schedules and biochemical modulators in an attempt to improve its therapeutic activity in advanced colorectal cancer. Combination chemotherapy regimens have not been developed because of the lack of other active agents. Recently, several novel agents are under clinical development for advanced colorectal cancer, including irinotecan, oxaliplatin, oral fluoropyrimidines, raltitrexed, monoclonal antibody 17-1A and tumour vaccines. Both irinotecan and oxaliplatin have uniquely different mechanisms of action compared to 5-FU, and have demonstrated activity in patients whose disease has progressed with 5-FU treatment. Recent randomised trials comparing 5-FU plus leucovorin (5-FU/LV) to combinations of either irinotecan or oxaliplatin plus 5-FU/LV have demonstrated that the addition of these novel agents to 5-FU improve response rates (RRs) and time to progression (TTP). The role and accept...
A survey of internet worm detection and containment

Self-duplicating, self-propagating malicious codes known as computer worms spread themselves without any human interaction and launch the most destructive attacks against computer networks. At the same time, being fully automated makes their behavior repetitious and predictable. This article presents a survey and comparison of Internet worm detection and containment schemes. We first identify worm characteristics through their behavior, and then classify worm detection algorithms based on the parameters used in the algorithms. Furthermore, we analyze and compare different detection algorithms with reference to the worm characteristics by identifying the type of worms that can and cannot be detected by these schemes. After detecting the existence of worms, the next step is to contain them. This article explores the current methods used to slow down or stop the spread of worms. The locations to implement detection and containment, as well as the scope of each of these systems/methods, are also explored in depth. Finally, this article points out the remaining challenges of worm detection and future research directions.
An integrated test generation tool for enhanced coverage of simulink/stateflow models

Simulink/Stateflow (SL/SF) is the primary modeling notation for the development of control systems in automotive and aerospace industries. In model based testing, test cases derived from a design model are used to show model-code conformance. Safety standards such as ISO 26262 recommend model based testing to show the conformance of a software with the corresponding model. From our experiments with various test generation techniques, we have observed that their coverage capabilities are complementary in nature. With this observation in mind, we have developed a new tool called SmartTestGen which integrates different test generation techniques. In this paper, we discuss SmartTestGen and the different test generation techniques utilized -- random testing, constraint solving, model checking and heuristics. We experimented with 20 production-quality SL/SF models and compared the performance of our tool with that of two prominent commercial tools.
Antimicrobial Activity in Vitro of Cefaclor, A New Oral Cephalosporin

The antimicrobial activity of cefaclor, a new orally administered cephalosporin derivative, was studied in vitro against a variety of Gram-positive and Gram-negative clinical isolates. Both penicillin-resistant and penicillin-susceptible strains of Staphylococcus aureus were susceptible to cefaclor, with mean MICs of 1.44 and 0.93 microgram/ml, respectively. However, the MBC for penicillin-resistant S. aureus was higher than that for the penicillin-susceptible strains. All strains of Streptococcus pyogenes, Streptococcus viridans, and Streptococcus pneumoniae tested were highly susceptible to cefaclor; all strains of Streptococcus faecalis were highly resistant to cefaclor. Strains of Escherichia coli, Klebsiella sp., Proteus mirabilis, and Hemophilus influenzae were susceptible to cefaclor. Eighty per cent of strains of H. influenzae were inhibited by 5 micrograms/ml of cefaclor. Most strains of Enterobacter sp., indole-positive Proteus, Pseudomonas sp., and Serratia sp. were resistant to cefaclor.
Electrophysiological Effects of 4-Hydroxynonenal, an Aldehydic Product of Lipid Peroxidation, on Isolated Rat Ventricular Myocytes

Abstract Aldehydic products of lipid peroxidation, such as 4-hydroxynonenal (4-HNE), have been implicated in the etiology of pathological changes under oxidative stress. To identify the mechanism by which 4-HNE alters cellular excitability, its effects on isolated rat ventricular myocytes were studied. Superfusion with 100 to 880 μmol/L 4-HNE led to a time- and concentration-dependent rigor shortening of myocytes. A reduction in [Ca2+]o and inhibition of transsarcolemmal Ca2+ transport by 1 mmol/L La3+ did not affect either the magnitude or the time course of 4-HNE–induced myocyte rigor. Superfusion of myocytes with 400 μmol/L 4-HNE led to an increase in the action potential duration, progressive depolarization of the resting membrane potential, and an increase in the input resistance (Rin) of the myocyte (phase I), followed by a loss of electrical excitability. Continued superfusion with 4-HNE resulted in membrane hyperpolarization and a prominent decrease in the Rin (phase II). The decrease in Rin coinc...
Model-based technique for super resolution and enhanced target characterization using a step-frequency radar: a simulation study

In this investigation, the signal reflected by a target to the step-frequency radar is processed using both non-parametric and parametric approaches. An autoregressive moving average (ARMA) model of the reflected signal is first used to estimate the location of the targets. Then, an extended Prony's method is used to estimate the magnitude of the reflection coefficients of the targets. These model-based approaches are found to provide super resolution and improvement in target characterization as compared to a conventional non-parametric approach. Several simulations are made to compare the performances of these methods.
[60]Fullerene Complexes with Supramolecular Zinc Tetraphenylporphyrin Assemblies: Synthesis, Crystal Structures, and Optical Properties

Different mono-, bi-, and tetradentate N- and O-containing ligands (L) were used in the design of monomer, dimer, and pentamer zinc tetraphenylporphyrin (ZnTPP) assemblies, which then cocrystallized with fullerene C60. Those were pyrazine (1); 4,4‘-bipyridyl (2, 8, 9 (with CoTPP)); tetra(4-pyridyl)porphyrin (3); tetrahydrofuran (4); N,N,N‘,N‘-tetramethyldiaminomethane (5); N,N,N‘,N‘-tetramethyldiaminoethane (6); N,N,N‘,N‘-tetramethyldiaminobutene (7); and 1,4-bi-(4,4‘-pyridyl)ethylene (10). Molecular structures of new ZnTPP oligomers were described. ZnTPP units, concaved as a result of ligand coordination, effectively cocrystallized with nearly spherical fullerene molecules to produce a variety of packing motifs of fullerenes, namely, three-dimensional (3D) packing in 4, one-dimensional (1D) zigzag chains in 6, a pair arrangement in 1 and 3, and isolated packing in 2. The Zn···N(L) bonds were either arranged nearly parallel to the planes of the ligand or bent up to 33° relative to this plane. The characte...
Particle Motions and the Dynamics of Korteweg-de Vries Solitons

The particlelike behaviour of the soliton solutions of nonlinear evolution equations, raises the question as to whether there exists a representation, in terms of classical particles, which gives quantitative as well as qualitative information about the dynamics of these interacting solitary waveforms. In this paper we establish such a representation for Kortewcg·dc Vries (KdV) solitons by locating the particles at the poles of the n-soliton solutions when the latter are considered as functions over a complex domain. The representation is shown to be faithful and a detailed analysis is presented for the one- and two-soliton solutions. In these cases the pole motions accurately reflect the behaviour of the solitons; giving, respec­ tively, a uniform motion and a repulsive interaction. Furthermore, in the case of the two­ soliton solutions, the phase shifts calculated from the particle trajectories are the same as those obtained from an asymptotic analysis of the waveforms. Since the KdV is not Galilean invariant, in the strict sense, the mass-spectrum of the pole-particles is obtained from the waveforms using a phenomenologically defined mass density rather than the Hamiltonian density. This mass-spectrum is then used to compute the forces and potentials acting between two solitons and an interpretation of the manner in which this interaction takes place is also given. Finally, a brief discussion of related work on other solutions of the KdV is presented.
Causes and Electoral Consequences of Party Policy Shifts in Multiparty Elections: Theoretical Results and Empirical Evidence

The spatial model of elections identifies factors that motivate party elites to shift their policy positions, including changes in voters' policy preferences, rival parties' policy shifts, past election results, and changes in party elites' valence images with respect to dimensions of evaluation such as competence and integrity. I review empirical studies on multiparty elections, i.e., elections involving three or more major parties, that evaluate party elites' policy responses to these factors, along with empirical studies on the electoral consequences of parties' policy shifts. This review reveals a paradox: on the one hand, empirical studies conclude that parties systematically shift their policy positions in response to the factors that spatial modelers have identified. On the other hand, there is only weak and inconsistent empirical evidence that voters actually perceive parties' policy shifts, and/or that these shifts have significant electoral consequences. Thus the predictions of spatial theory ar...
An Idealized Over-All Error-Correcting Digital Computer Having Only an Error-Detecting Combinational Part

The block diagram of an idealized over-all error-correcting digital computer is presented. This computer has the property that during each unit time interval, it can correct the effects of a specific maxium number of transient-type component failures which might occur anywhere within it. Yet, all its combinational logic circuitry is only of the error-detecting type. The corresponding reduction in equipment that this design feature makes possible is achieved at the expense of the computer's having to sit idle during a large percentage of those time intervals in which component failures occur. In a sense, therefore, the computer utilizes a great deal of time-domain redundancy as well as equipment-domain redundancy. This paper discusses some of the design requirements that are involved in using this type of redundancy structure.
Success and failure of the sociology of culture? Bringing the arts back

This articles brings up the most recent, internal discussions among researchers in the field of the sociology of arts, more precisely the thiking of experts who participated in a forum of culture organized in 2001. In her writing, Vera Zolberg accentuates, overall, the need for sociology of art to retain both its humanistic and scientific roots. She reminds that sociology of culture has developed from the sociology of art in recent decades. Next, she summarizes the tendencies and interests of researchers in the forum, by showing the fluidity of its possibilities and creative capacities. She mentions the most recent production in the field, proving that aesthetic elements play a crucial part in the sociological studies about the arts. According to Vera Zolberg, it is time to bring the arts back.
Conivaptan: Evidence supporting its therapeutic use in hyponatremia.

Introduction: The available treatment options for euvolemic and hypervolemic hyponatremia are limited, and consist mainly of fluid restriction, diuresis, or hypertonic solutions. Most of these therapies are neither well tolerated nor totally effective, and many are associated with significant adverse effects. Vasopressin receptor antagonists, also known as vaptans, are a new class of agents that now offer an additional treatment option for hyponatremic patients. Conivaptan hydrochloride, a competitive antagonist of vasopressin V1a and V2 receptors, is the first agent in this class to be approved for treatment of euvolemic and hypervolemic hyponatremia in hospitalized patients.
Room-Temperature Heterodyne Detection up to 110 GHz With a Quantum-Well Infrared Photodetector

A measurement of the photoresponse of a quantum-well infrared photodetector is presented. The detector response was measured from 80 K to 300 K. At 300 K, the high-frequency photocurrent response was measured up to 110 GHz and demonstrated a 1/omega decay
Start-up and sensor/parameter error transients in field oriented induction machines

This paper presents a tutorial investigation of the dynamic behavior of AC induction machine (IM) indirect field orientation (IFO). Physically intuitive descriptions complimented with analyses and simulations are used to illustrate the dynamics of IM IFO. Specifically, the process of rotor flux build-up from zero under various conditions is investigated. Additionally, how IM IFO systems react to and recover from the effects of sensor errors and estimated machine parameter errors is investigated and illustrated. Complex vectors and their relationship to the controller and machine reference frames are used extensively for both mathematical rigor and intuitive illustrations. In particular, the relative orientation between the controller and actual machine reference frames is exploited for the purposes of tutorial exposition. Computer simulations and known steady state results are used to substantiate and verify the results. It is the goal of this paper to present physically insightful illustrations and explanations, tutorial in nature, of the dynamics associated with IM IFO.
Watermarking of hyperspectral data

Watermarking is drawing the interest of researchers in many areas due to developments in sharing resources. Watermarked data helps protect ownership rights and provides a means of detecting illegal use. In this paper, an adaptive watermarking method based on the Redundant Discrete Wavelet Transform (RDWT) is proposed and applied to hyperspectral signatures.