cssi/SciSciGPT-SciSciNet huggingface dataset:
Efficient PDM sorting algorithms

In this paper we present efficient algorithms for sorting onthe The Parallel Disks Model (PDM). Numerous asymptotically optimalalgorithms have been proposed in the literature. However many of themhave large underlying constants in the time bounds. We present practicaland optimal algorithms in this paper. We have implemented thesealgorithms and evaluated their performance. Experimental data are verypromising.
Mitochondrial gene expression in diabetes mellitus: effect of nutrition.

Diabetes mellitus is a collection of genetic diseases that share a common phenotype: glucose intolerance. The genetic origins of this disease are being widely investigated. An estimated 0.1–9% of the population with diabetes has the disorder owing to one or more mutations in the mitochondrial genome. Diet can affect the expression of the genome as well as the function of its gene products. The antioxidant nutrients serve to protect this very vulnerable genome from oxidative damage. These nutrients may affect mitochondrial DNA transcription and nutrients that affect membrane fluidity affect the function of the gene products.
Corridors of power

Science under Control: The French Academy of Sciences 1795–1914. By Maurice Crosland. Cambridge University Press: 1992. Pp. 454. £60, $120.
The zero - bias - anomaly in doped M - O - M tunnel junctions: Effect of impurity interaction

Abstract A study of the magnetic field dependence of the zero-bias conductance peak as a function of impurity concentration in Fe-doped Al-Al 2 O 3 -Al tunnel junctions has been made. The role of impurity-impurity interactions is discussed.
Introduction to the reviews on neuropeptide Y

Neuropeptide Y (NPY) was first reported as an abundant peptide in brain tissue in 1982. Shortly thereafter, NPY was found to be a member of a peptide family consisting of the endocrine peptides pancreatic polypeptide (PP) and peptide YY (PYY). These peptides exert most of their biological effects through five G-protein coupled receptors termed Y1, Y2, Y4, Y5 and y6 that mediate either inhibition adenylate cyclase or increases in intracellular calcium. Since the discovery of NPY, a robust a body of literature has developed around the potential functions of this peptide. While initial findings identified NPY is an important contributor to the regulation of feeding, body weight and blood pressure, more recent work as revealed more subtle functions of this peptide and its potential role in affective disorders, bone formation and cravings. The accompanying twelve reviews detail important developments in our understanding of the functional role of NPY.
A Growing Digital Divide: Internet Freedom and the Negative Impact of Command-and-Control Networking

There is a growing consensus that communications is a fundamental right. However, achieving digital equality in the broadband age has become considerably more complex than just universal access. This article offers a more nuanced perspective on the widening digital divide that's centered on a user's utility of a broadband connection and outlines networking technologies that place control in users' hands.
Vascular problems of the pelvis

Vascular tumors of the pelvis are a rare, diverse group of neoplasms. These benign or malignant tumors can arise from the endothelium, smooth muscle cells, or pericytes of the arterial venous or lymphatic walls. They are rarely diagnosed by physical examination but more commonly seen with imaging studies such as computed tomography, magnetic resonance imaging, or angiography. Benign and malignant tumors can be differentiated pathologically by the two major anatomic characteristics of vascular channel formation and the regularity of endothelial cell proliferation. This review will focus on the clinical presentation, diagnosis, treatment, outcomes, and surgical approaches to benign and malignant vascular tumors of the pelvis.
On pebble automata

Abstract We look at two simple variations of space-bounded Turing machines (TM's): An off-line S(n) -space bounded TM where S(n) is below log n , which can use a pebble on the input tape, and a TM with two (or three) pebbles and no workspace. We show that in the former case, a pebble increases the recognition power of the device. The latter model(s) can accept large families of languages. For example, 2-pebble automata can accept languages accepted by deterministic checking stack automata, and 3-pebble automata can accept languages accepted by ‘stack-resetting’ two-way deterministic pushdown automata. Moreover, the pebble automata are halting (i.e., halt on all inputs).
The Molecular Mechanism and Evolution of the GA–GID1–DELLA Signaling Module in Plants

Bioactive gibberellins (GAs) are diterpene phytohormones that modulate growth and development throughout the whole life cycle of the flowering plant. Impressive advances have been made in elucidating the GA pathway with the cloning and characterization of genes encoding most GA biosynthesis and catabolism enzymes, GA receptors (GIBBERELLIN INSENSITIVE DWARF1, GID1) and early GA signaling components. Recent biochemical, genetic and structural analyses demonstrate that GA de-represses its signaling pathway by GID1-induced degradation of DELLA proteins, which are master growth repressors, via a ubiquitin–proteasome pathway. Multiple endogenous signals and environmental cues also interact with the GA–GID1–DELLA regulatory module by affecting the expression of GA metabolism genes, and hence GA content and DELLA levels. Importantly, DELLA integrates different signaling activities by direct protein–protein interaction with multiple key regulatory proteins from other pathways. Comparative studies suggest that the functional GA–GID1–DELLA module is highly conserved among vascular plants, but not in the bryophytes. Interestingly, differentiation of the moss Physcomitrella patens is regulated by as yet unidentified ent -kaurene-derived diterpenes, which are distinct from the common active GAs in vascular plants.
The Clinical Relevance of Cellular Drug Resistance Testing in Childhood Acute Myeloid Leukemia (AML)

The Clinical Relevance of Cellular Drug Resistance Testing in Childhood Acute Myeloid Leukemia (AML)
Modulation of pulmonary leukotriene formation and perfusion pressure by bestatin, an inhibitor of leukotriene A4 hydrolase.

We investigated the effects of bestatin, a prototype leukotriene A4 (LTA4 hydrolase inhibitor, on leukotriene (LT) formation and pulmonary artery perfusion pressure (Ppa) in isolated, perfused rat lungs. In lung parenchymal strips stimulated with a 10 μM concentration of the Ca2+ ionophore A23187, bestatin inhibited LTB4 formation with an IC50 = 10.4 ± 3.0 μM (mean ± SD, N = 4). It did not alter cysteinyl LT formation, confirming that it inhibited LTA4 hydrolase selectively, without inhibiting phospholipase, 5-lipoxygenase, or LTC4 synthase. In isolated, perfused lungs stimulated with 10 μM A23187, 300 μM bestatin inhibited LTB4 release by 72.2 ± 10.6% (mean ± SEM, N = 6, P 0.5). In these perfused lungs, bestatin did not alter the change in Ppa following stimulation with A23187. This effect is consistent with the insubstantial re-direction of LTA4 toward formation of vasospactic cysteinyl LTs. Separate experiments used lungs from rats treated with lipopolysaccharide endotoxin in vivo, prior to isolation, perfusion, and stimulation with 5 μm formyl-methionyl-leucyl-phenylalanine, in vitro. In these inflamed lungs, 750 μM bestatin inhibited LTB4 formation (P < 0.05) and increased LTE4 formation (P < 0.05), compatible with selective inhibition of LTA4 hydrolase. The re-direction of LTA4 metabolism toward formation of cysteinyl LTs by inflamed, perfused lungs did not cause an increase in Ppa.
Three-dimensional structure of the Martian nightside ionosphere: Predicted rates of impact ionization from Mars Global Surveyor magnetometer and electron reflectometer measurements of precipitating electrons

[1] The nightside ionosphere of Mars is known to be highly variable: electron densities are below detection thresholds in certain regions and are almost comparable to the photoionization-produced dayside ionosphere in others. The factors controlling its structure include thermospheric densities, temperatures and winds, day-night plasma transport, plasma temperatures, current systems, meteoroid ablation, solar and galactic energetic particle events, and magnetic field geometry-topology and electron precipitation, none of which are adequately understood at present. Using a kinetic approach called Mars Monte Carlo Electron Transport, we model the dynamics of precipitating electrons on the nightside of Mars to study the impact of these last two listed factors (magnetic fields and electron precipitation) on ionospheric structure. As input, we use precipitating electron energy spectra and pitch angle distributions from the Mars Global Surveyor Magnetometer and Electron Reflectometer. We thus calculate ionization rate in three dimensions, both for specific observations and average cases. The very highest average rates are equivalent to photoionization rates on the dayside at high solar zenith angle. We predict complex geometrical patterns in the ionization and huge variability (∼4 orders of magnitude) in peak ionization rates, both on single orbits and between the averages for different geographic regions, and find a bimodal distribution of predicted ionization rates where the highest rates correlate with the most vertical magnetic fields. This model can be used as input to electrodynamic models of the Mars ionosphere, which can be compared with, and informed by, data from the upcoming 2013 Mars Atmosphere and Volatile Evolution Mission.
The Antioxidant Response Element and Oxidative Stress Modifiers in Airway Diseases

Redox balance is particularly important in the airways because they are the first points of contact with environmental pollutants such as ozone, particles, and cigarette smoke, as well as pathogens such as bacteria and viruses. However, an imbalance between toxicant-induced reactive oxygen (ROS) and nitrogen (RNS) species and the antioxidant defense system leads to oxidative stress, which has been implicated in the development and/or perpetuation of airway diseases, including malignancy. Various antioxidant enzymes and proteins are critical to maintaining the reducing environment of the cell and preventing the damage to various biomolecules that is elicited by ROS/RNS. Emerging evidence indicates that transcriptional activation of the antioxidant response element (ARE) plays a crucial role in modulating oxidative stress and providing cytoprotection against prooxidant stimuli. This review focuses on the regulation and functional roles of key effectors that bind to the ARE and differentially (up- or down-) regulate gene expression in lung tissue/cell types in response to respiratory toxicants. It also provides a perspective on whether boosting ARE-mediated gene expression with dietary plants and synthetic plant products will offer a better therapeutic strategy for mitigating oxidative stress and respiratory pathogenesis.
NUCLEAR MAGNETIC RESONANCE STUDIES OF LIVING MUSCLE.

Measurements of nuclear magnetic relaxation times for protons of water in living skeletal frog muscle show the transverse relaxation time, T 2 , increases when a muscle contracts isometrically. This result and other experimental data suggest that a fraction of the intracellular water molecules have restricted rotational freedom and that this fraction decreases when contraction occurs.
A CSF-1 Receptor Phosphotyrosine 559 Signaling Pathway Regulates Receptor Ubiquitination and Tyrosine Phosphorylation

Receptor tyrosine kinase (RTK) activation involves ligand-induced receptor dimerization and transphosphorylation on tyrosine residues. Colony-stimulating factor-1 (CSF-1)-induced CSF-1 receptor (CSF-1R) tyrosine phosphorylation and ubiquitination were studied in mouse macrophages. Phosphorylation of CSF-1R Tyr-559, required for the binding of Src family kinases (SFKs), was both necessary and sufficient for these responses and for c-Cbl tyrosine phosphorylation and all three responses were inhibited by SFK inhibitors. In c-Cbl-deficient macrophages, CSF-1R ubiquitination and tyrosine phosphorylation were substantially inhibited. Reconstitution with wild-type, but not ubiquitin ligase-defective C381A c-Cbl rescued these responses, while expression of C381A c-Cbl in wild-type macrophages suppressed them. Analysis of site-directed mutations in the CSF-1R further suggests that activated c-Cbl-mediated CSF-1R ubiquitination is required for a conformational change in the major kinase domain that allows amplification of receptor tyrosine phosphorylation and full receptor activation. Thus the results indicate that CSF-1-mediated receptor dimerization leads to a Tyr-559/SFK/c-Cbl pathway resulting in receptor ubiquitination that permits full receptor tyrosine phosphorylation of this class III RTK in macrophages.
Thermal Unfolding of Gelatin in Solids as Affected by the Glass Transition

The thermal unfolding or denaturation of solid-state proteins during processing can affect their functionality. This project explored the relation between the glass transition temperature (T g ) and thermal unfolding temperature (T m ) using gelatin as a model system. Freeze-dried gelatin was prepared containing various polyol types at several concentrations. Using differential scanning calorimetry, T m and T g were determined. Moisture and polyols (that is, glycerol, xylitol, sorbitol, sucrose, and trehalose) promoted a lowering of both T and T m , the extent of which depended upon the plasticizer type and concentration. For all the data, T m > T g , and a pfot of T m against T g indicated a linear relationship (R 2 = 0.95). These results suggest that formulations must be in the rubbery state to have the necessary mobility for hydrogen bond disruption that leads to protein unfolding. Glass transition data should be considered when developing processing parameters for proteinaceous systems.
Electrical Resistivity, Pulse Velocity, and Compressive Properties of Carbon Fiber-Reinforced Cement Mortar

The electrical resistivity and mechanical properties of carbon fiber-reinforced cement mortar (CFRCM) were investigated. Both cylindrical and prism specimens were used in this investigation to determine the effects of size and shape of specimen on the physical and mechanical properties of the CFRCM systems. Carbon fiber loading was varied up to 6% (w/w), and water-to-cement ratios (w/c) of 0.5 and 1 were used. The specific electrical resistivity of the plain mortar with w/c ratio of 1 (>66,000 Ohm m) was reduced to 3,750 and 0.23 Ohm m upon increasing the carbon fiber content to 1 and 6% (w/w), respectively. The percolation theory was used to represent the variation of the electrical specific resistivity with fiber content in the cement mortar. Increasing the w/c ratio decreased the strength and toughness of the CFRCM composites. Increasing the fiber content increased the peak strain and toughness, but decreased the Young's modulus and electrical resistivity of cement mortar composites. Pulse velocity tests showed that the specimen shape also affected the dynamic Young's modulus, dynamic shear modulus, and the dynamic Poisson's ratio. The compression strength of the CFRCM was influenced by the w/c ratio and the fiber content. A model was used to predict the compressive stress-strain behavior of different CFRCM systems, and relations between static and dynamic properties have been developed. Empirical relations were developed to relate the specific electrical resistivity to unit weight, Young's modulus, and pulse velocity.
New bend insensitive fiber products enabled deep penetration in MDU and FTTP inside wiring

The emergent of True-Bend-Insensitive-Fiber product is a major triumph for the fiber optics industry. By defining the requirements and understanding the trade-offs in optical performance, large-scale manufacturing compatibility, standards compliance, mechanical performance, compatibility with field equipments and installation procedures will be critical to identify the most cost effective alternative.
Mixed Protein Blends Composed of Gelatin and Bombyx mori Silk Fibroin: Effects of Solvent-Induced Crystallization and Composition

Novel protein blends have been prepared by mixing gelatin (G) with Bombyx mori silk fibroin (SF) and using aqueous methanol (MeOH) to post-induce SF crystallization. When co-cast from solution, amorphous blends of these polymers appear homogeneous, as discerned from visual observation, microscopy, and Fourier-transform infrared (FTIR) spectroscopy. Upon subsequent exposure to aqueous MeOH, SF undergoes a conformational change from random coil to β sheet. This transformation occurs in pure SF, as well as in each of the G/SF blends, according to X-ray diffractometry and thermal calorimetry. The influence of MeOH-induced SF crystallization on structure and property development has been ascertained in terms of preparation history and blend composition. Thermal gravimetric analysis reveals that the presence of β sheets in SF and G/SF blends improves thermal stability, while extensional rheometry confirms that SF crystallization enhances the tensile properties of the blends. By preserving a support scaffold abo...
Memory B cells from older people express normal levels of cyclooxygenase-2 and produce higher levels of IL-6 and IL-10 upon in vitro activation.

Worldwide the elderly population is increasing. The elderly show deficiencies in immune function. B lymphocytes are essential elements of the immune system responsible for antibody production. This laboratory previously showed that activated human B cells isolated from young adults express cyclooxygenase-2 (Cox-2) and that Cox-2 is essential for optimal antibody responses. Recent data suggests that Cox-2 expression decreases with age in mouse bone tissue. There is no information regarding Cox-2 expression in B cells from older human subjects. We investigated the expression and activity of Cox-2 in naive and memory B cells from older people. We show that B cells from older subjects show similar Cox-2 protein expression and activity, antibody production and proliferation compared to younger people. However, we found that activated memory B cells from older people produce higher levels of IL-6 and IL-10 compared to young adults. Therefore, the dysregulated cytokine production could contribute to immune senescence in the elderly.
Adsorption and desorption studies of 4He on Nuclepore by capacitance techniques.

Measurements of the adsorption and desorption of $^{4}\mathrm{He}$ on the porous polycarbonate substrate Nuclepore are reported for nominal pore diameters of 30, 50, 80, and 200 nm. The isotherms are measured directly by a newly developed capacitance technique. The theory of Saam and Cole, relevant to capillary condensation in cylindrical pores, is examined and confirmed by the data. Pore distributions for the several Nuclepore samples are determined by two techniques.
Embeddings of 2-dimensional cell complexes in S3 determined by their 1-skeletons

Abstract We prove the following theorem: A polyhedral embedding of a 2-dimensional cell complex in S 3 is determined up to ambient isotopy rel the 1-skeleton by the embedding of the 1-skeleton, provided the cell complex is ‘proper’ and ‘fine enough’. Applications of the theorem are given in distinguishing certain graphs in S 3 from their mirror images. (This is of interest to chemists studying stereoisomerism.) Examples are given to illustrate that the theorem can fail without either hypothesis ‘proper’ or ‘fine enough’. The main theorem may be generalized by replacing S 3 by an irreducible 3-manifold with nonempty boundary.
Separation of non-proliferating from proliferating thymic lymphocytes based on light scatter analysis.

Two populations of thymic lymphocytes from eight-week-old mice were separated based on the light scatter intensity they generated while passing through a flow cell analyser. The two populations were subsequently studied morphologically and analysed for the relative amount of DNA present in each cell. Cells having a low light scatter intensity had a high nuclear: cytoplasmic ratio, a heterochromatic nucleus, and a proliferative index (S + G2 + M) of only 23%. Cells with a high light scatter intensity had a low nuclear: cytoplasmic ratio, dispersed chromatin, frequently a uropod with budding microvilli and a proliferative index of 71%. The low light scatter cells resemble small cortical thymocytes or lymphocytes from the thoracic duct described by others. The highest light scatter cells resemble medium lymphocytes shown by others to be proliferative.
Corrosion Inhibition of Stress Corrosion Cracking and Localized Corrosion of Turbo-Expander and Steam/Gas Turbines Materials

Stress corrosion cracking of 7050 aluminum alloys and ASTM A470 steel in the turbo expander and steam/gas turbine industry can cause expensive catastrophic failures, especially for turbo machinery systems performing in hostile, corrosive environments. Commercially available inhibitors were investigated for their effectiveness in reducing and controlling the corrosion susceptibility. Inhibitor effectiveness was confirmed with electrochemical corrosion techniques in different solutions. Polarization resistance increased with concentration of corrosion inhibitor due to film formation and displacement of water molecules. Cyclic polarization behavior for samples in the 1.0% and 5.0% inhibitors showed a shift in the passive film breakdown potential. The substantial increase in the passive range has positive consequences for neutralizing pitting and crevice corrosion cell chemistry. The strain to failure and tensile strength obtained from the slow strain rate studies for both alloys showed pronounced improvement due to corrosion inhibitor ability to mitigate SCC; the fractographic analysis showed a changed morphology with ductile overload as the primary failure mode instead of transgranular or intergranular cracking.
Energy Dependence of the Parameter C NN in pp Elastic Scattering between 2 and 6 GeV/ c

We have measured the spin--spin correlation parameter C/sub NN/ at 2, 3, 4, and 6 GeV/c over the abs. value t range of 0.1 to 2.0 (GeV/c)$sup 2$ and have observed a striking energy and abs. value t dependence in C/sub NN/. Polarization data were simultaneously collected and are compared to previous results. (AIP)
Systemic IGF-I treatment inhibits cell death in diabetic rat retina

Diabetic retinopathy can result in apoptotic cell death of retinal neurons, as well as significant visual loss. It is further known that insulin-like growth factor (IGF) levels are reduced in diabetes and that IGF-I can prevent cell death in many cell types. In this study, we tested the hypothesis that systemic treatment with IGF-I could inhibit death of neuroretinal cells in diabetic rats by examining the expression of proapoptotic markers. In diabetic rat retina, the number of TUNEL-immunoreactive cells increased approximately sixfold in the photoreceptor layer (P<.001) and eightfold in the inner nuclear layer (INL; P<.001); phospho-Akt (p-Akt; Thr 308) immunoreactivity increased eightfold in the ganglion cell layer (GCL; P<.001) and threefold in the INL (P<.01). Subcutaneous IGF-I treatment significantly reduced the number of TUNEL (P<.001) and p-Akt immunoreactive retinal cells (P<.05) in diabetic rats approximately to the level of the nondiabetic group. Qualitative results showed that caspase-3 and BAD immunoreactivities were also elevated in diabetes and reduced in IGF-I-treated animals. Elevated TUNEL and p-Akt immunoreactivities were localized to distinct cell layers in the retina of diabetic rats. Early intervention with systemic IGF-I reduced the presence of proapoptotic markers indicative of neuroretinal cell death, despite ongoing hyperglycemia and weight loss. The eye is a special sensory organ, and these data show that cell loss in the nervous system, even in uncontrolled diabetes, can be prevented by IGF-I administration.
Genetics and imaging to assess oocyte and preimplantation embryo health

Two major criteria are currently used in human assisted reproductive technologies (ART) to evaluate oocyte and preimplantation embryo health: (1) rate of preimplantation embryonic development; and (2) overall morphology. A major gene that regulates the rate of preimplantation development is the preimplantation embryo development (Ped ) gene, discovered in our laboratory. In mice, presence of the Ped gene product, Qa-2 protein, results in a fast rate of preimplantation embryonic development, compared with a slow rate of preimplantation embryonic development for embryos that are lacking Qa-2 protein. Moreover, mice that express Qa-2 protein have an overall reproductive advantage that extends beyond the preimplantation period, including higher survival to birth, higher birthweight, and higher survival to weaning. Data are presented that suggest that Qa-2 increases the rate of development of early embryos by acting as a cell-signalling molecule and that phosphatidylinositol-3 � kinase is involved in the cell-signalling pathway. The most likely human homologue of Qa-2 has recently been identified as human leukocyte antigen (HLA)-G. Data are presented which show that HLA-G, like Qa-2, is located in lipid rafts, implying that HLA-G also acts as a signalling molecule. In order to better evaluate the second criterion used in ART (i.e. overall morphology), a unique and innovative imaging microscope has been constructed, the Keck 3-D fusion microscope (Keck 3DFM). The Keck 3DFM combines five different microscopic modes into a single platform, allowing multi-modal imaging of the specimen. One of the modes, the quadrature tomographic microscope (QTM), creates digital images of non-stained transparent cells by measuring changes in the index of refraction. Quadrature tomographic microscope images of oocytes and preimplantation mouse embryos are presented for the first time. The digital information from the QTM images should allow the number of cells in a preimplantation embryo to be counted non-invasively. The Keck 3DFM is also being used to assess mitochondrial distribution in mouse oocytes and embryos by using the k-means clustering algorithm. Both the number of cells in preimplantation embryos and mitochondrial distribution are related to oocyte and embryo health. New imaging data obtained from the Keck 3DFM, combined with genetic and biochemical approaches, have the promise of being able to distinguish healthy from unhealthy oocytes and embryos in a non-invasive manner. The goal is to apply the information from our mouse model system to the clinic in order to identify one and only one healthy embryo for transfer back to the mother undergoing an ART procedure. This approach has the potential to increase the success rate of ART and to decrease the high, and undesirable, multiple birth rate presently associated with ART.
Shockwave Acceleration and Attenuation in Glow Discharge Argon Plasma

Experimental investigations of the shockwave propagation in the direction parallel to the electric field in low-pressure longitudinal glow discharge argon plasmas are performed by the simultaneous multipoint laser deflection technique. In the newly developed shock tube at Troy University, Mach 1.5-2.2 shockwaves are produced by a fast capacitor discharge (quarter period tau1/4 = 1.4 mus ). In this paper, the shock propagation measurements are extended to the low pressure limit down to 3.6 torr while confirming the earlier measurements performed at gas pressures 15 torr and above. The shockwaves are launched through a plasma medium inside the shock tube, where the deflections of the laser beams are recorded on a fast oscilloscope. An average shockwave velocity in the plasma is determined from the time history of the laser deflection signals. The shockwave speed and the broadening of the laser deflection signals in the plasma are found to be dependent on the plasma discharge current. Shockwave speeds increase by 18% for the plasma at 3.6 torr over a range of plasma discharge current I = 0-150 mA and by 46% for the plasma at 15 torr over I = 7-150 mA. In addition, shockwave amplitudes are attenuated in the plasma and show linear dependence on the shockwave speed or Mach number.
Relationships between perceived features and similarity of images: A test of Tversky's contrast model

The rapid growth of the numbers of images and their users as a result of the reduction in cost and increase in efficiency of the creation, storage, manipulation, and transmission of images poses challenges to those who organize and provide access to images. One of these challenges is similarity matching, a key component of current content-based image retrieval systems. Similarity matching often is implemented through similarity measures based on geometric models of similarity whose metric axioms are not satisfied by human similarity judgment data. This study is significant in that it is among the first known to test Tversky's contrast model, which equates the degree of similarity of two stimuli to a linear combination of their common and distinctive features, in the context of image representation and retrieval. Data were collected from 150 participants who performed an image description and a similarity judgment task. Structural equation modeling, correlation, and regression analyses confirmed the relationships between perceived features and similarity of objects hypothesized by Tversky. The results hold implications for future research that will attempt to further test the contrast model and assist designers of image organization and retrieval systems by pointing toward alternative document representations and similarity measures that more closely match human similarity judgments. © 2007 Wiley Periodicals, Inc.
Observer-based estimation of selective catalytic reduction catalyst ammonia storage:

AbstractThis paper presents two non-linear observer designs with different robustness to estimate engine selective catalytic reduction (SCR) ammonia coverage ratio. The observers estimate the SCR catalyst ammonia storage (or coverage ratio) based on the available measurements of NOx, NH3, and temperature. An extended Kalman filter is proposed to eliminate the NOx sensor cross-sensitivity to ammonia. A sliding mode observer technique was employed for the design. The robustness of the observers with respect to sensor measurement uncertainties was theoretically analysed. FTP75 test cycle simulation results show the robustness and estimation accuracies of the different observers in the presence of different measurement errors/uncertainties.
Influence of moisture and food supply on the movement dynamics of a nonbreeding migratory bird (Parkesia noveboracensis) in a seasonal landscape

ABSTRACT. We radiotracked Northern Waterthrushes (Parkesia noveboracensis) in four habitats in Puerto Rico during two winters (i.e., January–April) in 2003 and 2004 to determine the ecological determinants of diurnal space use and overwinter sitepersistence in this species. The majority of birds (69%) were sedentary and used a contiguous area within a single habitat over the winter period. A smaller percentage (31%) initially used a contiguous area within a single habitat but then permanently moved from that area to another disjunct location (mean = 418 m). Most of these movements were out of the two habitats (dry forest and Black Mangrove) that became the driest from January to mid-March and into wetter mangrove areas. The primary determinants of movement probability were moisture and food availability on each bird's home range. Foraging areas of birds that eventually moved were drier and had lower food availability than areas used by site-persistent individuals. The sites that these itinerant birds move...
Second Hugoniot relationship for solids

The term second Hugoniot is used to describe a locus of states directly attainable by shock compression beginning with an initial state that has itself been achieved by shock compression. For many materials the principal Hugoniot is linear in the shock velocity-particle velocity [Us — up] representation. A second Hugoniot for such materials is not linear in this representation, but the nonlinear effects can often be neglected if the compressions are not too great. These results are based on the Mie-Gruneisen equation of state and are more or less independent of the explicit functional dependence of the Gruneisen parameter. A criterion to evaluate the magnitude of nonlinear effects is posed and Mg and Pb are treated as examples. Calculated second Hugoniots are compared with experimental results for regular reflection in Mg, Pb and U. For these materials nonlinear effects are not important from a practical standpoint for final volumetric compressions to roughly two-thirds of the initial volume. Some future experimental work is also suggested.
Designing networks for selfish users is hard

We consider a directed network in which every edge possesses a latency function specifying the time needed to traverse the edge given its congestion. Selfish, noncooperative agents constitute the network traffic and wish to travel from a source s to a sink t as quickly as possible. Since the route chosen by one network user affects the congestion (and hence the latency) experienced by others, we model the problem as a noncooperative game. Assuming each agent controls only a negligible portion of the overall traffic, Nash equilibria in this noncooperative game correspond to s-t flows in which all flow paths have equal latency. We give optimal inapproximability results and approximation algorithms for several network design problems of this type. For example, we prove that for networks with n nodes and continuous, nondecreasing latency functions, there is no approximation algorithm for this problem with approximation ratio less than n/2 (unless P = NP). We also prove this hardness result to be best possible by exhibiting an n/2-approximation algorithm. For networks in which the latency of each edge is a linear function of the congestion, we prove that there is no (4/3 - /spl epsi/)-approximation algorithm for the problem (for any /spl epsi/ > 0, unless P = NP); the existence of a 4/3-approximation algorithm follows easily from existing work, proving this hardness result sharp.
Clar theory for molecular benzenoids.

Eric Clar’s ideas concerning “aromatic sextets” are extended to a quantitative format in terms of a polynomial called the “Clar 2-nomial”, along with related derivative quantities. The quantification is successfully tested to make correlations with a selection of numerical data, including resonance energies, bond lengths, and NICS ring-aromaticity values.
Intellectual Property in Medical Imaging and Informatics: The Independent Inventor’s Perspective

While innovation and new product development is traditionally thought of as the exclusive domain of industry and academia, a large number of innovations in medicine and information technology have come from independent inventors, which account for almost 30% of new patents issued in the U.S. today. A large number of economic, political, and legal challenges exist within the current marketplace that serves as relative impediments to independent invention. This article explores the existing challenges facing the independent inventor and offers a number of recommendations and resources to facilitate independent inventors in their quest for innovation and entrepreneurship. The concept of “outsourcing innovation” is discussed as an alternative to the existing model of industry sponsored research and development (R&D), with the goal of combining the unique attributes and strengths of independent inventors and industry sponsors.
Computer analysis and observation of streamer growth at a dielectric interface

A simulation study of streamer growth within a dielectric liquid at a solid interface was undertaken. Using the finite element method with computer graphics, the shape of the growing streamer was determined and plotted. In addition, the changing voltage and electric field values within the dielectric were calculated, and simulated images of these parameters produced. The behavior of the streamer is based on the formation of a localized gas phase discharge and the growth of the resulting plasma within the liquid. The model determines an inception site and predicts a growth path that depends on the electric field immediately surrounding the streamer tip. Two liquids, n-hexane and water, both with an interface, were investigated using the simulation model. The effect of the choice of the liquid and the solid dielectric, in addition to the geometry, was explored. For mixed solid and liquid insulation, the results show that streamer growth depends on the permittivity mismatch between the two materials. Experimental findings are presented that show streamer growth for different interfacial conditions. A good correlation is observed between the theoretical and experimental work.
Recording and Analysis of AC Impedance Data for Corrosion Studies

Abstract Experimental approaches for recording ac impedance data are discussed in this paper. Considerations of the high frequency performance of potentiostats and reference electrodes are given an...
Expression of CD30 (Ber-H2) in nasopharyngeal carcinoma, undifferentiated type and lymphoepithelioma-like carcinoma. A comparison study with anaplastic large cell lymphoma

Aims : Undifferentiated nasopharyngeal non-keratinizing carcinoma (UNPC), formerly known as lymphoepithelioma, frequently metastasizes at an early stage to regional lymph nodes and, thus, may be difficult to distinguish from Hodgkin's lymphoma (HL) or anaplastic large cell lymphoma (ALCL). CD30 expression is a useful diagnostic stain in both HL and ALCL, but its expression in UNPC deserves clarification. The aim of this study was to evaluate CD30 expression in UNPC and lymphoepithelioma-like carcinoma (LELC) from other anatomic locations and compare it with ALCL and squamous cell carcinoma (SCC). Methods and results : CD30 immunoreactivity was examined in 38 cases of primary or metastatic UNPC, six cases of LELC, 10 cases of SCC and seven cases of ALCL. CD30 immunoreactivity was observed in four of 38 (10.5%) cases of UNPC. CD30 staining was absent in all cases of LELC (0/6) and SCC (0/10). All cases of ALCL (7/7) were strongly positive for CD30. Conclusions : The majority of cases of UNPC are immunohistochemically negative for CD30; however, a small subset of cases expresses CD30 antigen. These findings provide additional evidence that CD30 expression is not restricted to neoplasms of lymphoid origin. This should be taken into consideration when interpreting CD30 immunohistology and the possibility of UNPC.
Use of Sentinel Chickens to Evaluate the Effectiveness of Cleaning and Disinfection Procedures in Noncommercial Poultry Operations Infected with Exotic Newcastle Disease Virus

The use of sentinel chickens in establishing the negative status of commercial poultry flocks depopulated due to exotic Newcastle disease (END) is considered to be an economically beneficial process. However, the costs and benefits of using sentinel chickens in noncommercial operations are in question. The objective of this study was to use sentinel chickens to evaluate whether adequate cleaning and disinfection coupled with an appropriate time period without susceptible poultry species on the premises would eliminate END virus from a noncommercial poultry operation and preclude the need for placement of sentinels in previously infected operations before declaring them free of virus. Noncommercial poultry operations were selected from the 2002 to 2003 END outbreak database. Operations included in the study had one or more isolations of END virus (ENDV) from cloacal or oropharyngeal swabs of birds on the premises. A total of 546 birds were placed on 53 premises. All sentinel birds sampled after placements were negative by virus detection methods and serologic tests. Results of this study indicate that time and the application of appropriate cleaning and disinfection procedures will adequately mitigate the risk of viable virus persisting in noncommercial poultry operations. In the future, this information may eliminate the need for sentinel bird placement to ensure virus free status of premises before repopulation, thereby decreasing the costs of END eradication.
Force decay evaluation of thermoplastic and thermoset elastomeric chains: A mechanical design comparison

Objectives: To compare the following over a period of 8 weeks: (1) force decay between thermoplastic (TP) and thermoset (TS) elastomeric chains; (2) force decay between light (200-g) and heavy (350-g) initial forces; and (3) force decay between direct chains and chain loops (stretched from one pin around the second pin and back to the first pin). Materials and Methods: TP and TS chains were obtained from American Orthodontics TM (AOTP, AOTS) and ORMCO TM (OrTP, OrTS). Each of the four chain groups was subdivided into four subgroups with 10 specimens per subgroup: (1) direct chains light force, (2) direct chains heavy force, (3) chain loops light force, and (4) chain loops heavy force. The experiment was performed in artificial saliva (pH of 6.75) at 37uC. Results: A significant difference was found between TP and TS chains, with an average mean difference of around 20% more force decay found in the TP chains (P , .001, a 5 .05). There was no significant difference between direct chains and chain loops except in OrTP, in which direct chains showed more force decay. There was also no significant difference in force decay identified when using light vs heavy forces. Conclusions: TS chains decayed less than TP chains, and chain loop retraction was beneficial only when using OrTP chains. Contrary to the interchangeable use of TP and TS chains in the published literature and in clinical practice, this study demonstrates that they perform differently under stress and that a clear distinction should be made between the two. (Angle Orthod. 2014;84:1026–1033.)
Modeling Real-time Garbage Collection Cost

Given the major advantages of productivity and safety, the use of garbage collection (GC) in real-time systems has gained increasing attention. Guaranteeing garbage collection activities' worst-case execution time (WCET) is necessary for a real-time system to perform scheduling and schedulability analysis. This paper describes a detailed GC cost model for incremental mark-and-sweep GC exemplified by a modified Boehm-Demers-Weiser (BDW) collector. The GC cost model computes the WCET for garbage collection in terms of (1) the performance of collector operations and (2) the garbage collection load offered by a real-time task. Separating these aspects is a step along the road to an engineering approach to garbage collection in real-time systems, allowing prediction of system behavior from knowledge of component behavior and environmental specifications. The model incorporates the cost of write barriers that are needed to support incremental GC. To be useful for real-time systems, a model's predicted WCET must be no less than the actual WCET. However, unreasonably large overestimates are also problematic as they may lead to the incorrect conclusion that the application cannot be feasibly scheduled. A pessimism metric assesses the degree to which the model's predictions exceed the measured worst-case cost in particular instances.
International Relations Theory and the Case against Unilateralism

What are the general costs associated with a U.S. shift toward unilateralism? According to the overwhelming majority of international relations (IR) scholars, the costs are very high. We evaluate the key arguments that underlie this assessment, namely that increased U.S. unilateralism will: (1) spur the formation of a coalition to check U.S. power; (2) reduce efficiency gains through lost opportunities for institutionalized cooperation; and (3) undermine the legitimacy of the American-led international order. We conclude that the theoretical arguments that IR scholars advance do not show that a shift toward unilateralism necessarily has high costs. Our analysis reveals the need to, first, distinguish clearly between criticisms of unilateral policies based on procedure and those based on substance and, second, to recognize the weakness of current procedural arguments.Stephen G. Brooks is assistant professor (Stephen.G.Brooks@Dartmouth.edu), and William C. Wohlforth is professor (William.C.Wohlforth@Dartmouth.edu) in the Department of Government at Dartmouth. They are currently writing a book entitled The Challenge of American Primacy. The authors thank the three anonymous reviewers for Perspectives on Politics and, especially, Erik Voeten for detailed critical comments. They are also grateful to Mlada Bukovansky, Ian Hurd, Martha Finnemore, Ben Valentino, Nina Tannenwald, Alex Wendt, and participants at seminars at the Dickey Center at Dartmouth College, the Olin Institute at Harvard University, the Mershon Center at Ohio State University, and the Norwegian Institute of International Affairs. Thanks also to Dartmouth's Rockefeller and Dickey Centers for supporting research on which this article draws.
The reversion reactions of D-glucose during the hydrolysis of cellulose with dilute sulfuric acid

Abstract The reversion products formed during the acid hydrolysis of Avicel to d -glucose, under conditions envisaged for the industrial conversion of woody biomass into monomeric sugars, have been determined by using gas-liquid chromatography. Avicel was hydrolyzed in dilute sulfuric acid (0.26–1.27 wt.%) between 160 and 250° in small (3 mm, i.d.) glass tubes at a 3:1 liquid-to-solid ratio. The anhydro sugars, levoglucosan and 1,6-anhydro-β- d -glucofuranose, were produced in the ratio of 7:3 and ocnstituted > 50% of the total yield of reversion products. The yield of anhydro sugar followed equilibrium kinetics, and reached 6% at maximum yields (50%) of d -glucose. Isomaltose and gentiobiose were the most preponderant disaccharides found among the reversion products, constituting together ∼25% of the reversion products. The (1→2)- and (1→3)-linked α-disaccharides preponderated over their β counterparts. The total yields of reversion products approached 10% on the basis of the d -glucose theoretically available.
Drag Reduction Studies Using Active Flow Control

Active flow control (AFC) has gained a great deal of attention in recent flow control research and applications. Use of AFC has shown improvement in aircraft performance by reduction in drag and increase in lift. The objective of the present study is to understand the physical mechanisms behind drag reduction. Two configurations that are prime candidates for drag reduction through separation control have been studied. The first configuration is a NACA 0036 airfoil whose shape is similar to that of a helicopter rotor hub covered with a shroud. The second is a bluff body reminiscent of a backward facing step. Due to the bluff body shape, in both cases, separation occurs near the aft end of the body. These are thus suitable candidates for studying flow control and drag reduction. Active flow control at a fixed chord location has been studied and the flow field examined for underlying causes. Comparisons to experiments are given wherever possible. The effect of the jet on turbulent quantities has been analyzed. Based on this analysis, possible causes of drag reduction have been hypothesized.