cssi/SciSciGPT-SciSciNet huggingface dataset:
The compass that steered robotics

Robotics researchers will be aware of Dexter Kozen's contributions to algebraic algorithms, which have enabled the widespread use of the theory of real closed fields and polynomial arithmetic for motion planning. However, Dexter has also made several important contributions to the theory of information invariants, and produced some of the most profound results in this field. These are first embodied in his 1978 paper On the Power of the Compass , with Manuel Blum. This work has had a wide impact in robotics and nanoscience. Starting with Dexter's insights, robotics researchers have explored the problem of determining the information requirements to perform robot tasks, using the concept of information invariants. This represents an attempt to characterize a family of complicated and subtle issues concerned with measuring robot task complexity. In this vein, several measures have been proposed [14] to measure the information complexity of a task: (a) How much internal state should the robot retain? (b) How many cooperating robots are required, and how much communication between them is necessary? (c) How can the robot change (side-effect) the environment in order to record state or sensory information to perform a task? (d) How much information is provided by sensors? and (e) How much computation is required by the robot? We have considered how one might develop a kind of "calculus" on (a) --- (e) in order to compare the power of sensor systems analytically. To this end, information invariants is a theory whereby one sensor can be "reduced" to another (much in the spirit of computation-theoretic reductions), by adding, deleting, and reallocating (a) --- (e) among collaborating autonomous robots. As we show below, this work steers using Dexter's compass.
Nested motion descriptors

A nested motion descriptor is a spatiotemporal representation of motion that is invariant to global camera translation, without requiring an explicit estimate of optical flow or camera stabilization. This descriptor is a natural spatiotemporal extension of the nested shape descriptor [2] to the representation of motion. We demonstrate that the quadrature steerable pyramid can be used to pool phase, and that pooling phase rather than magnitude provides an estimate of camera motion. This motion can be removed using the log-spiral normalization as introduced in the nested shape descriptor. Furthermore, this structure enables an elegant visualization of salient motion using the reconstruction properties of the steerable pyramid. We compare our descriptor to local motion descriptors, HOG-3D and HOG-HOF, and show improvements on three activity recognition datasets.
Discriminative stimulus properties of the serotonin agonist 1-(3-trifluoromethylphenyl)piperazine (TFMPP)

Abstract Using a standard two-lever drug discrimination procedure, twelve rats were trained to discriminate 1.0 mg/kg of the serotonin (5-HT) agonist TFMPP from saline. Once trained, the animals displayed a dose-related decrease in discriminative performance upon administration of lower doses of TFMPP. Tests of stimulus generalization were performed using the purported 5-HT agonist RU-24,969 and 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane (DOM). While TFMPP produced stimulus effects similar to those of RU-24,969, these effects seem to be dissimilar to those of DOM. The results of the present study suggest that the discriminative stimulus effects of TFMPP may involve a 5-HT 1 -related mechanism.
Magnetic heat capacity of an amorphous Gd-Al alloy

Abstract The magnetic specific heat of amorphous GdAl 2 shows a broad maximum near 17.5 K, the temperature of the spin-glass-like cusp in the magnetic susceptibility. At low temperatures it varies as T 3 2 , with a small negative intercept. This is interpreted in terms of ferromagnetic spin waves excited in regions some 35 A in size.
Cancer Therapeutics: Best Informed by Genes or Genomes?

Cancer is a heterogeneous disease, even when from the same tissue of origin. By examining the molecular profiles of 373 endometrial carcinomas, researchers from the Cancer Genome Atlas Research Network have indeed identified four molecularly defined disease subtypes that may inform treatment decisions––but based on characteristics of the cancer genomes rather than on specific gene mutations. The authors obtained 363 profiles of somatic copy number alteration, 248 exome sequencing profiles, 333 mRNA expression profiles, 293 protein expression profiles, 367 microRNA expression profiles, and 373 DNA methylation profiles. The genomic data (copy number alterations, somatic mutations, and microsatellite instability) defined four disease subtypes. Unsupervised clustering of the samples on the basis of mRNA expression and methylation profiles was consistent with the same four subtypes. Two of the subtypes––ultramutated and serous-like––were strongly associated with good and poor prognosis, respectively. The ultramutated group had high mutation frequencies and mutations of POLE , a gene that encodes an enzyme involved in DNA replication and repair. The serous-like group had low mutation rates but extensive copy number alterations; the poor prognosis of this group is in accord with findings that genomic instability (as reflected in abnormalities such as copy number alterations) correlate with poor prognosis in many other cancers. The authors also identified recurrently mutated genes, which corresponded to previously well-characterized cancer-related genes (with the notable exception of POLE ). However, the subclasses of endometrial cancer were more clearly discriminated by their coarse-grained genomic characteristics (frequency of mutation and copy number alterations) than by (combinations of) specific mutations or activated pathways (although POLE mutations caused high overall mutation rates). In the prevailing view of cancer therapy’s future, genomic data from an individual’s tumor will reveal mutational profiles that show a small number of driver events (gene gain/loss of function events that lead to pathway activation), which in turn will determine the appropriate targeted therapeutic regimen. In contrast to this view, the results in this paper suggest that general features of endometrial tumor genomes (mutation frequency and copy number variation) are sufficient to inform choices among conventional treatment alternatives (radiotherapy versus chemotherapy). In fact, categorizing these cancers into the new genomic subtype groups described by the authors would reclassify up to 25% of high-grade endometroid tumors as uterine serous-like carcinomas––therefore indicating a different adjuvant therapy for these patients: chemotherapy instead of radiotherapy. The Cancer Genome Atlas Research Network, Integrated genomic characterization of endometrial carcinoma. Nature 497 , 67–73 (2013). [[Full Text]][1] [1]: http://www.nature.com/nature/journal/v497/n7447/full/nature12113.html
Quasicrystal equilibrium state.

We obtain quasicrystalline structures in Monte Carlo simulations of a simple two-component Lennard-Jones system in two dimensions. The quasicrystal, which shows tenfold symmetry, appears to be an equilibrium state of the system. Although the structure corresponds to tiling of the plane with rhombuses, it is not a Penrose pattern.
Penultimate effect in ethylene-styrene copolymerization and the discovery of highly active ethylene-styrene catalysts with increased styrene reactivity.

For the first time commercially relevant catalysts for the copolymerization of ethylene and styrene have been identified. The catalysts maintain very high copolymer efficiencies at relatively high reactor temperatures without sacrificing styrene comonomer reactivity. The observations which led to this discovery are based upon the kinetic analysis of ethylene−styrene copolymerization using constrained geometry catalyst (η5-C5Me4)(SiMe2-N-t-Bu)TiMe2 (1). This analysis revealed a substantial styrene penultimate monomer effect. Inherent reactivity of 1 toward styrene is greatly improved when the penultimate monomer on the growing polymer chain is styrene rather than ethylene. The presence of a penultimate styrene effect led to the hypothesis that catalysts bearing aromatic moieties in close proximity to the active site could lead to enhancement of styrene reactivity for this catalyst family. This hypothesis was born out by two new constrained geometry catalysts, one having two phenyl substituents placed in th...
Perceptions of Parent-Child Attachment, Social Self-Efficacy, and Peer Relationships in Middle Childhood.

Relationships among attachment to each parent, children's social self-efficacy, and the quality of peer relations (attachment to peers and perceptions of victimization) were explored with 67 fifth and sixth graders (31 female) attending a rural elementary school. Results of hierarchical multiple regression analyses revealed main effects for gender and attachment to mother relative to the attachment to peers variable, with girls and more securely attached children reporting higher quality attachment to peers. Main effects were also detected for gender and attachment to father relative to social self-efficacy, with girls and more securely attached children exhibiting higher self-efficacy. No main effects were observed relative to the peer victimization variable. None of the interaction effects involving gender and attachment to each parent relative to attachment to peers, peer victimization, and social self-efficacy were significant. Finally, evidence for mediation of attachment to father on attachment to peers by children's social self-efficacy was revealed. Implications of the results are discussed and ideas for future research are provided. Copyright © 2003 John Wiley & Sons, Ltd.
TILLING by sequencing to identify induced mutations in stress resistance genes of peanut ( Arachis hypogaea )

Targeting Induced Local Lesions in Genomes (TILLING) is a powerful reverse genetics approach for functional genomics studies. We used high-throughput sequencing, combined with a two-dimensional pooling strategy, with either minimum read percentage with non-reference nucleotide or minimum variance multiplier as mutation prediction parameters, to detect genes related to abiotic and biotic stress resistances. In peanut, lipoxygenase genes were reported to be highly induced in mature seeds infected with Aspergillus spp., indicating their importance in plant-fungus interactions. Recent studies showed that phospholipase D (PLD) expression was elevated more quickly in drought sensitive lines than in drought tolerant lines of peanut. A newly discovered lipoxygenase (LOX) gene in peanut, along with two peanut PLD genes from previous publications were selected for TILLING. Additionally, two major allergen genes Ara h 1 and Ara h 2, and fatty acid desaturase AhFAD2, a gene which controls the ratio of oleic to linoleic acid in the seed, were also used in our study. The objectives of this research were to develop a suitable TILLING by sequencing method for this allotetraploid, and use this method to identify mutations induced in stress related genes. We screened a peanut root cDNA library and identified three candidate LOX genes. The gene AhLOX7 was selected for TILLING due to its high expression in seeds and roots. By screening 768 M2 lines from the TILLING population, four missense mutations were identified for AhLOX7, three missense mutations were identified for AhPLD, one missense and two silent mutations were identified for Ara h 1.01, three silent and five missense mutations were identified for Ara h 1.02, one missense mutation was identified for AhFAD2B, and one silent mutation was identified for Ara h 2.02. The overall mutation frequency was 1 SNP/1,066 kb. The SNP detection frequency for single copy genes was 1 SNP/344 kb and 1 SNP/3,028 kb for multiple copy genes. Our TILLING by sequencing approach is efficient to identify mutations in single and multi-copy genes. The mutations identified in our study can be used to further study gene function and have potential usefulness in breeding programs.
Energy and carbon accounting to compare bioenergy crops

To compare the utility of current and future biofuels and biofuel feedstocks in an objective manner can be extremely challenging. This challenge exists because agricultural data are inherently variable, experimental techniques are crop-dependent, and the literatures usually report relative, rather than absolute, values. Here, we discuss the ‘PETRO approach’, a systematic approach to evaluate new crops. This approach accounts for not only the capture of solar energy but also the capture of atmospheric carbon (as CO 2 ) to generate a final carbon-based liquid fuel product. The energy yield, per unit area, of biofuel crops grown in different climate zones can thus be benchmarked and quantitatively compared in terms of both carbon gain and solar energy conversion efficiency.
Probing structure and dynamics in liquid crystalline microdomains by infrared spectroscopy

Abstract While infrared spectroscopy is employed generally to characterize various physical phenomena, spectroscopic applications to macromolecular-liquid crystal (LC) composites have been limited to obtaining LC phase transitions and orientation information. We employ both Fourier transform infrared (FTIR) spectroscopy and FTIR spectroscopic imaging to delineate quantitatively the formation, microstructure and molecular dynamics within a flexible polymer-LC composite. Specifically, phase diagrams, molecular orientational and conformational order and transient molecular reorganizations of the LC upon application of an electric field are determined. The flexible and electrically unresponsive macromolecular component is found to be a dynamic entity during the nematic phase organization and reorientation processes demonstrating the necessity of including polymer segmental contributions to both phase separation and LC dynamics studies.
Problematic alcohol use and HIV risk among Black men who have sex with men in Massachusetts

Abstract This analysis was designed to explore the frequency of problem drinking and its role in potentiating HIV risk among a community-recruited sample of Black men who have sex with men (MSM) in Massachusetts. Black MSM (n=197) recruited via modified respondent-driven sampling between January and July 2008 completed an interviewer-administered survey, including HIV sexual behavior, the Center for Epidemiologic Studies Depression Scale (CES-D), and the CAGE alcohol screener. Bivariate and multivariable logistic regression procedures examined the association of behavioral HIV-risk factors and other psychosocial variables with problematic alcohol use (CAGE score 3 or 4). Overall, 29% of the sample was found to abuse alcohol. In a multivariable model adjusting for demographic and behavioral variables, factors associated with increased odds of problem drinking were: (1) depressive symptoms (CES-D 16+ ); (2) one or more episodes of serodiscordant unprotected anal sex during last sexual encounter with a casua...
Reduced-fat bologna manufactured with poultry skin connective tissue gel

Abstract The objectives of this study were to determine temperature (50, 60, 70, and 80 C) and time (0.5, 1.0, 1.5, and 2.0 h) effects on the water binding ability of chicken skin connective tissue (CCT) and its ability to form model gels; to develop and determine the functionality of added water (AW, 100, 200, and 300%) CCT gels; and to evaluate the attributes of reduced-fat bologna containing 10 to 30% addition of 100 to 300% AW CCT gels. Determination of water binding and holding capacities, and objective textural and color attributes provided data suggesting the practicality of developing and incorporating AW CCT gels as water binders in reduced-fat bologna. Processing qualities, and textural and sensory attributes were analyzed to assess the feasibility of manufacturing a reduced-fat processed poultry product containing a modified poultry by-product. Heating (60 C) CCT for 0.5 h allowed the formation of model CCT gels containing 100 to 300% AW. Added water decreased CCT gel fat, protein, collagen content, and hardness due to a protein (collagen) dilution. Hydration values were sufficient to allow CCT to bind up to 300% AW. Gel fragility and syneresis were observed in higher AW CCT gels due to protein dilution, a result of the high fat content of raw CCT (approximately 40%) and added water. Percentage gel addition and AW decreased (P
CEO compensation: The role of individual performance evaluation

Abstract We investigate use of individual performance evaluation in CEOs' annual incentive plans. In contrast with relatively objective accounting and stock-price-based measures, individual performance evaluation may involve discretion and subjectivity, as well as nonfinancial and financial performance criteria. Based on agency theory, we predict that individual performance evaluation increases with the importance of growth opportunities relative to assets in place, length of product development and product life cycles, and noise in traditional financial measures. Using proprietary compensation data, we find evidence that individual performance evaluation increases with growth opportunities and product time horizon.
Effects of Flame Lift-Off on the Differences Between the Diffusion Flames From Circular and Elliptic Burners

An experimental study conducted to determine the effects of lifting the flame base off the burner rim on the differences between the flame characteristics of diffusion flames from circular and elliptic burners is presented. The in-flame profiles of temperature, concentrations offuel and combustion product species, and the mean and fluctuating components of axial velocity are presented. This study has shown that the effects of burner geometry in turbulent lifted flames are considerable only in the near-burner region. In the midflame and far-burner regions, the effects traceable to burner geometry are much weaker, contrary to those observed in the attached flame configuration. The observations are attributed to the turbulence and additional air entrainment into the jet prior to the flame base accompanying the lift-off process, which mitigate the effects of burner geometry.
Genetic modifiers of neurological disease

Genetic modifiers make an important contribution to neurological disease phenotypes. Significant progress has been made by studying genetic modifiers in model organisms. The ability to study complex genetic interactions in model systems contributes to our understanding of the genetic factors that influence neurological disease. This will lead to the development of novel therapeutic strategies and personalized treatment based on genetic risk.
Using Feminist and Social Structural Analysis to Focus on the Health of Poor Women

Poverty results in both personal and structural deprivation for women. Health status and health care are intimately affected by this deprivation. As a result, the increasing rates of poverty among women have serious immediate and long-term consequences for their overall health status. Feminist and social structural analyses are crucial to a comprehensive understanding of poor women's health. Critical to these perspectives is the premise that the underlying structure of American society has produced a social stratification system that has grossly unequalized life chances for poor women. This inequity deleteriously affects poor women's health behaviors, health outcomes, and the health care delivery services that are accessible to them. An adequate understanding of poor women's health calls for an in-depth examination of health and behavior and the social contextual framework within which they occur, taking into account poor women's position in society, the communities in which they live, and the stressful life events they experience.
Reversibility of Effects of Very Hypotonic Fluids on in Vitro Frog Gastric Mucosa: A Functional and Morphological Study

Functional and morphological properties of the in vitro frog gastric mucosa were studied during and after exposure to very hypotonic (approximately 25 mOs M) solutions. Within 20 min the acid secretory rate decreased to zero, but it returned to normal levels after isotonic fluids had been restored. The potential difference (PD) dropped within the first minutes after the exposure to hypotonic solutions, and became inverted. Following the return of isotonic conditions the PD increased to levels higher than in the controls. The electrical resistance increased about 10-fold during the hypotonic period, but decreased to near normal values when isotonic conditions were restored. By light and electron microscopy the cells of the hypotonic mucosae appeared greatly swollen, and the alterations were assessed by morphometric methods. The gland lumina were almost obliterated, and the lamina propria was reduced to about 63% of its former volume. After the return to isotonic conditions normal morphology was restores. It is conceivable that the great increase in resistance duroing the hypotonic period was caused by the occlusion of the gland lumina. Quantitative analyses of the Na, K, and Cl tissue concentrations indicated a large loss of these ions during the hypotonic state. Presumably the epithelial cells in the hypotonic mucosae avoid bursting by rapidly letting large numbers of ions exit, which results in a celulular osmolarity close to that of the bathing fluids.
Evidence on the fit of the log-linear income model versus a general statistical specification

Abstract Using the March 1985 Current Population Survey, we predict the size distribution of family income as a function of various family characteristics. Pitting the ‘standard’ log-linear specification against a multinomial specification, we find the multinomial model reproduces more closely the actual distribution.
Bottomland hardwood forests of Southern Illinois-regeneration and succession.

. 1958. Principles concerned in the formation and classification of communities. Botan. Rev. 24: 65-125. Lodge, R. W. 1954. Effect of grazing on the soils and forage of mixed prairie in southwestern Saskatchewan. J. Range Mgmt. 7: 166-170. Looman, J., and J. B. Campbell. 1960. Adaptation of Sorenson's K (1948) for estimating unit affinities in prairie vegetation. Ecology 41: 409-416. Lynch, Brother Daniel, C.S.C. 1955. Ecology of the aspen groveland in Glacier County, Montana. Ecol. Monographs 4: 321-344. McIntosh, R. P. 1958. Plant communities. Science 128: 115-120.
Cooperation between JNK1 and JNK2 in activation of p53 apoptotic pathway

FDH (10-formyltetrahydrofolate dehydrogenase) is strongly downregulated in tumors while its elevation suppresses proliferation of cancer cells and induces p53-dependent apoptosis. We have previously shown that FDH induces phosphorylation of p53 at Ser6, which is a required step in the activation of apoptosis. In the present study, we report that FDH-induced p53 phosphorylation is carried out by JNK1 and JNK2 (c-Jun N-terminal kinases) working in concert. We have demonstrated that FDH induces phosphorylation of JNK1 and JNK2, while treatment of FDH-expressing cells with JNK inhibitor SP600125, as well as knockdown of JNK1 or JNK2 by siRNA, prevents phosphorylation of p53 at Ser6 and protects cells from apoptosis. Interestingly, the knockdown of JNK1 abolished phosphorylation of JNK2 in response to FDH, while knockdown of JNK2 did not prevent JNK1 phosphorylation. Pull-down assay with the p53-specific antibody has shown that JNK2, but not JNK1, is physically associated with p53. Our studies revealed a novel mechanism in which phosphorylation of JNK2 is mediated by JNK1 before phosphorylation of p53, and then p53 is directly phosphorylated by JNK2 at Ser6.
The Similarity of States: Using S to Compute Dyadic Interest Similarity

Several leading international relations theories argue that the degree of interest similarity is an important determinant of dyadic conflict and cooperation. Empirical scholars have long wrestled with operationalizing and measuring this central, yet elusive, concept. Signorino and Ritter's (1999) S algorithm, combined with multiple data sources, provides an attractive solution to this problem. To date, however, many scholars have failed to take full advantage of this solution. In this research note we examine the properties of S via simulation and with real data sources, highlighting its virtues and potential limitations. In particular, we stress the need to include multiple data sources in the computation and provide scholars with an easy-to-use tool to greatly simplify this task.
Diminished interaction of norepinephrine with climbing fiber inputs to cerebellar Purkinje neurons in aged Fischer 344 rats.

Abstract The ability of norepinphrine (NE) to modulate climibign fiber activation of complex site discharge in cerebellar Purkinje neurons was compared in young (3–6 months) and aged (18–20 months) Fischer 344 rats. In young rats, NE selectively inhibits spontaneous activity while climbing fiber evoked activity remains intact or increased. NE also increases the probability of observing 4 bursts of full-sized action potentials rather than partially inactivated action potentials in the complex spike. In older rats, both of these modulatory actions of NE on climbing fiber complex spike activation are markedly diminished. These data support the concept that age-related reductions in catecholamine modulation of synaptic inputs may contribute to CNS dysfunction found in senescence.
ADIABATIC SHEAR BANDS IN THE TAYLOR IMPACT TEST FOR A WHA ROD

We analyse the development of shear bands in axisymmetric, thermomechanical defor- mations of a circular tungsten heavy alloy (WHA) rod impacting at normal incidence a smooth rigid target. The rod's material is modeled either as a mixture of Fe-Ni-W particles interspread randomly among the W-particles or as a homogeneous alloy. For comparison purposes we also analyse deformations of a pure W and an Fe-Ni-W rod. It is found that shear bands, defined as narrow regions of rapid intense plastic deformation, form near the transition between the mush- roomed region and the relatively undeformed portion of the rod, when its material is either a mixture of Fe-Ni-W and W particles or a homogeneous alloy but no such bands form in rods made of either W or Fe-Ni-W only. This could be due to the diAerent initial softening rates of the materials. # 1998 Elsevier Science Ltd. All rights reserved
Protein Interactions and Transition Times that Influence the Pathogenesis of Protein Folding Diseases

Protein folding diseases occur when a specific protein fails to fold into its correct functional state as a consequence of mutation in the protein amino acid sequence. In this talk, I present a model of the folded and misfolded protein expression, processing and their interactions, which we have used to investigate how protein folding disease phenotypes develop from mutated genotypes. Modeling protein processing as a continuous flow reactor, we found that the pathogenesis of protein folding diseases can be modulated by a combination of the transition time of folded and misfolded proteins in the reactor, the ratio of folded and misfolded protein inflow rates in the reactor and a chemical interaction parameter between folded and misfolded proteins. Our analysis reveals therapeutic strategies targeting the modulation of protein folding diseases, which have been recently explored in cellular and animal models of Mutant INS-gene Induced Diabetes of Youth and Congenital Hypothyroidism with deficient thyroglobulin.
Widespread endocrine disruption and reproductive impairment in an estuarine fish population exposed to seasonal hypoxia

The long-term effects on marine fish populations of the recent increase worldwide in the incidence of coastal hypoxia are unknown. Here we show that chronic environmental exposure of Atlantic croaker (Micropogonias undulatus) to hypoxia in a Florida estuary caused marked suppression of ovarian and testicular growth which was accompanied by endocrine disruption. Laboratory hypoxia studies showed that the endocrine disruption was associated with impairment of reproductive neuroendocrine function and decreases in hypothalamic serotonin (5-HT) content and the activity of the 5-HT biosynthetic enzyme, tryptophan hydroxylase. Pharmacological restoration of hypothalamic 5-HT levels also restored neuroendocrine function, indicating that the stimulatory serotonergic neuroendocrine pathway is a major site of hypoxia-induced inhibition. Inhibition of tryptophan hydroxylase activity to downregulate reproductive activity could have evolved as an adaptive mechanism to survive periodic hypoxia, but in view of the recent increased incidence of coastal hypoxia could become maladaptive and potentially affect fish population abundance and threaten valuable fishery resources.
Vaporizing foil actuator: A tool for collision welding

Abstract A method for implementing collision welding at moderate to small length scales has been developed. The flyer, instead of being driven by chemical explosives (explosive welding) or magnetic forces (magnetic pulse welding), is launched toward the target by the pressure created from the electrically driven rapid vaporization of a thin metallic conductor. Mechanical impulse is developed from 0.0762 mm thick aluminum foils, which are vaporized using capacitor bank discharge with nominal charging voltage of 5.5 kV and peak current on the order of 100 kA delivered with rise times of about 12 μs. Welding couples of copper–titanium, copper–steel, aluminum–copper, aluminum–magnesium and titanium–steel have been successfully created with the same input parameters such as foil geometry, input energy and standoff distance. Instrumented peel tests, lap shear tests and optical and scanning electron microscopy reveal a wide spectrum of both strengths and interface structures. Copper–titanium and copper–steel welds are strong and have characteristic wavy interfaces with little intermetallics or void formation. The other combinations are seen to have brittle interfaces with intermetallics and defects, with the collision welding parameters used presently. For the titanium–steel system, a thin nickel interlayer is introduced and all the layers are welded in a single experiment. Peel strength of the weld was observed to be quadrupled. Peak velocities of up to 560 m/s were obtained for titanium flyer sheets.
Autoinhibition in polystyrene photo-oxidation

Abstract Oxygenated functional groups are produced in polystyrene (PS) film upon exposure to 254 nm UV in air. At UV dosages much above 10 −4 E/cm 2 , however, these functional groups accumulate in the film at a decreasing rate, as judged by infrared spectroscopy. Oxygen uptake experiments were performed to study PS photo-oxidation at high UV dosages. It was found that the buildup of functional groups in PS film stopped at UV dosages that caused autoinhibition according to the oxygen uptake method.
Length Scales in the Convective Boundary Layer

Abstract We calculated integral scales for horizontal and vertical velocity components, temperature, humidity and ozone concentration, as well as for their variances and covariances from aircraft measurements in the convective atmospheric boundary layer over both ocean and land surfaces. We found that the integral scales of the second-order moment quantities are 0.67± 0.09 that of the variables themselves. Consequently, only the second-order moment integral scales are presented here. These results are used to calculate the averaging lengths necessary to measure second-order moment quantities to a given accuracy. We found that a measurement length of 10 to 100 times the boundary-layer height is required to measure variances to 10% accuracy, while scalar fluxes require a measurement length of 102 to 104 and stress a measurement length of 103 to 105 times the boundary layer height. We also show that the ratio of the wavelength of the spectral peak to the integral scale can be used to estimate the sharpness o...
0.25μm CMOS Dual Feedback Wide-Band UHF Low Noise Amplifier

This paper presents a CMOS low noise amplifier (LNA) for UHF band applications. By using an inverter to enhance the overall transconductance, and a resistive shunt feedback topology with a source degenerated inductor, a wide bandwidth from 50 MHz to 560 MHz is achieved, with a peak power gain of 13.8 dB. A noise figure of 1.8 to 2.4 dB is obtained in the frequency range of 200 MHz and 1.5 GHz. At 450 MHz, this LNA exhibits IIP3 of 6.15 dBm, and input P1dB of -6 dBm. The LNA is biased at 2.4 V, drawing a current of 14 mA. Compared to other published wide-band LNAs, this amplifier achieves the best linearity for NF below 2.5 dB, with low circuit complexity.
Tensor representation of color images and fast 2D quaternion discrete Fourier transform

In this paper, a general, efficient, split algorithm to compute the two-dimensional quaternion discrete Fourier transform (2-D QDFT), by using the special partitioning in the frequency domain, is introduced. The partition determines an effective transformation, or color image representation in the form of 1-D quaternion signals which allow for splitting the N × M-point 2-D QDFT into a set of 1-D QDFTs. Comparative estimates revealing the efficiency of the proposed algorithms with respect to the known ones are given. In particular, a proposed method of calculating the 2r × 2r -point 2-D QDFT uses 18N2 less multiplications than the well-known column-row method and method of calculation based on the symplectic decomposition. The proposed algorithm is simple to apply and design, which makes it very practical in color image processing in the frequency domain.
Hepatocellular carcinoma in the very elderly: To treat or not to treat?

We report a case of a patient with hepatocellular carcinoma (HCC) who has two unusual features. The patient was 95 years old at the time of diagnosis and his excellent response to treatment. The authors briefly review the age distribution of HCC and the treatments used. We concluded that therapy should not be arbitrarily withheld based solely on chronological age. Older cancer patients deserve the right to be treated if they so wish.
A nonlinear, resistive boundary layer in rotating hydromagnetic flow

Abstract A new nonlinear boundary layer in rotating hydromagnetic flows is presented. The purpose of this layer is to provide a smooth transition between the magnetic field at a rigid, electrically insulating boundary and that far from the boundary. The boundary layer problem is solved in a cylindrical geometry, assuming that the variables obey the hydromagnetic analog of the von Karman similarity. The primary momentum balance within this boundary layer is between pressure, Coriolis and hydromagnetic forces; the viscous and nonlinear inertia forces are unimportant. Diffusion of the magnetic field is balanced by advection where the advecting fluid flow is induced by the action of the hydromagnetic body forces within the boundary layer. The structure of the layer depends upon a single parameter which measures the strength of the normal magnetic field. Steady solutions are presented and their uniqueness and temporal stability are analyzed. The relevance of this layer to the core of the Earth is discussed. It is estimated that this boundary layer would be at least as thick as one tenth of the core radius if it exists within the core.
A surface cleaning method for sputter deposition of pure titanium film onto TiNi shape memory alloy substrate

In order to establish the surface cleaning method for sputter deposition of pure titanium film onto TiNi shape memory alloy substrate, the effects of wiping the substrate surface with cotton gauze soaked with organic solvent on adhesion of the deposited film to the alloy substrate were investigated. The titanium film deposited by DC sputtering onto the alloy substrate surface wiped with the gauze followed by ultrasonic cleaning with organic solvent was adhesive to the substrate, durable and was not damaged by the tip of a pincette, while the one cleaned only by the ultrasonic cleaning without being wiped with the gauze separated from the substrate for the most part. Based on the results of AES analysis, it was found that the surface cleaned only by ultrasonic cleaning, and not by wiping with the gauze had a considerable amount of adherent residue such as the diamond paste and the lapping oil, not removed by the ultrasonic cleaning, which caused the separation of the film from the substrate. Therefore, wiping the surface of TiNi shape memory alloy substrate with cotton gauze soaked with organic solvent followed by ultrasonic cleaning with the organic solvent was found to be considerably effective in the removal of adherent residue thereby improving the adhesion of the deposited pure titanium film to the alloy substrate.
Phylogenetic systematics of the viviparous halfbeak genera Dermogenys and Nomorhamphus (Teleostei: Hemiramphidae: Zenarchopterinae)

Abstract Among the 13 genera and over 100 species of halfbeaks, three genera –Dermogenys,Nomorhamphus and Hemirhamphodon– are internally fertilized and viviparous. These genera belong to a more inclusive clade, the Zenarchopterinae, that also includes Zenarchopterus, inferred to be internally fertilized and to lay fertilized eggs, and the monotypic Tondanichthys, also inferred to be internally fertilized. Whereas the Hemiramphidae are distributed worldwide, internally fertilized halfbeaks are restricted to Southeast Asia. Recent data from histological surveys of the gonads of both males and females as well as embryonic modifications associated with viviparity have been combined here with osteological characters in a phylogenetic analysis. Results indicate overwhelming support for a sister-group relationship betweenHemirhamphodon and (Dermogenys+Nomorhamphus). Monophyly of theDermogenys +Nomorhamphus clade is also well supported. These results confirm earlier suggestions thatDermogenys , as previously defined, is paraphyletic. Within the Dermogenys+Nomorhamphus clade, two monophyletic clades are supported: one comprises ten species including four new species (Dermogenys bruneiensis,Dermogenys robertsi , Dermogenys palawanensis and Dermogenys collettei) and the other comprises 13 species including three undescribed species (Nomorhamphus rossi, Nomorhamphus pinnimaculata and Nomorhamphus manifesta). Diagnoses for the species of Dermogenys and Nomorhamphus, as well as a natural classification for the included species, are presented.
Lattice-Dynamical Calculation of the Surface Specific Heat of a Crystal at Low Temperatures

A lattice-dynamical calculation of the surface contribution to the low-temperature specific heat of a crystal is presented. The free boundary surfaces of a crystal are treated as a perturbation of an unperturbed crystal in which the atomic displacements satisfy the cyclic boundary condition. The general theory developed in this paper is illustrated by applying it to a nearest- and next-nearest-neighbor central-force model of a simple cubic crystal, whose force constants are chosen in such a way that it is elastically isotropic in the long-wavelength limit. The result for the low-temperature surface specific heat obtained here agrees with the results of earlier calculations by Dupuis, Mazo, and Onsager, and by Stratton, which were based on elasticity theory.
Mitigating Thermal Effects on Clock Skew with Dynamically Adaptive Drivers

On-chip temperature gradient emerged as a major design concern for high performance integrated circuits for the current and future technology nodes. Clock skew is an undesirable phenomenon for synchronous digital circuits that is exacerbated by the temperature difference between various parts of the clock tree. We investigate the effect of on-chip temperature gradient on the clock skew for a number of temperature profiles. As an effective way of mitigating the clock skew, we present an adaptive circuit technique that senses the temperature of different parts of the clock tree and adjusts the driving strengths of the corresponding clock buffers dynamically to reduce the clock skew. Simulation results demonstrate that with minimal area overhead our adaptive technique is capable of reducing the skew by 72.4%, on the average, leading to much improved clock synchronization and design performance
Combined intraepithelial squamous neoplasia and atypical fibroxanthoma of the cornea and limbus

Abstract PURPOSE: To investigate a case of an unusual neoplasm of the cornea and limbus. METHODS: A 59-year-old man presented with a highly vascularized, nodular mass involving the left cornea and limbus. An excisional biopsy and, subsequently, a superficial lamellar keratectomy and multiple conjunctival biopsies were performed. At the 6-month follow-up examination, repeat conjunctival biopsies were performed. RESULTS: Histopathologic examination of the corneal specimen showed a high-grade intraepithelial squamous neoplasia (in situ carcinoma) overlying an atypical fibroxanthoma. CONCLUSION: We report the clinical and histologic appearance of a corneal/limbal neoplasm consisting of an intraepithelial squamous neoplasia and an atypical fibroxanthoma.
Precision machining and polishing of scintillating crystals for large calorimeters and hodoscopes

New machining and polishing techniques have been developed for large barium fluoride scintillating crystals that provide crystalline surfaces without sub-surface damage or deformation as verified by Atomic Force Microscopy (AFM) and Rutherford Back-scattering (RBS) analyses. Surface roughness of about 10--20 angstroms and sub-micron mechanical tolerances have been demonstrated on large crystal samples. Mass production techniques have also been developed for machining and polishing up to five 50 cm long crystals at one time. We present this technology along with surface studies of barium fluoride crystals polished with this technique. This technology is applicable for a number of new crystal detectors proposed at Colliders including the Barium Fluoride Electromagnetic Calorimeter at SSC, the Crystal Clear Collaboration`s cerium fluoride calorimeter at LHC, and the KTeV and PHENIX scintillating hodoscopes at Fermilab, and RHIC, respectively. Lawrence Livermore National Laboratory (LLNL) has an active program of study on barium fluoride scintillating crystals for the Barium Fluoride Electromagnetic Calorimeter Collaboration and cerium fluoride and lead fluoride for the Crystal Clear Collaboration. This program has resulted in a number of significant improvements in the mechanical processing, polishing and coating of fluoride crystals. Techniques have been developed using diamond-loaded pitch lapping that can produce 15 angstrom RMSmore » surface finishes over large areas. Also, special polishing fixtures have been designed based on mounting technology developed for the 1.1 m diameter optics used in LLNL`s Nova Laser. These fixtures allow as many as five 25--50 cm long crystals to be polished and lapped at the same time with tolerances satisfying the stringent requirements of crystal calorimeters. We also discuss results on coating barium fluoride with UV reflective layers of magnesium fluoride and aluminum.« less
Benefits and Risks of Social Networking Sites: Should they also be Used to Harness Communication in a College or University Setting

One of the challenges facing university and college professors is the use of effective and efficient communication with their students. One solution could be the use of social networking sites to engage students and the U.S. 2010 Digital Year in Review (2011), social networking continues to grow as one of the webâ€™s top activities with 9 out of every 10 U.S. Internet users accessing break down communication barriers, according to a social networking site every month. The study includes an in-depth review of the uses, benefits and risks of social networking sites as well as how they might be utilized in a college or university setting. The researcher in this study surveyed university business students at a private, four-year, Hispanic-serving institution in Texas about their use of social networking sites and how professors might integrate these sites into the curriculum.
Modulation of PPAR activity via phosphorylation.

Abstract Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily of transcription factors that respond to specific ligands by altering gene expression in a cell-, developmental- and sex-specific manner. Three subtypes of this receptor have been discovered (PPARα, β and γ), each apparently evolving to fulfill different biological niches. PPARs control a variety of target genes involved in lipid homeostasis, diabetes and cancer. Similar to other nuclear receptors, the PPARs are phosphoproteins and their transcriptional activity is affected by cross-talk with kinases and phosphatases. Phosphorylation by the mitogen-activated protein kinases (ERK- and p38-MAPK), Protein Kinase A and C (PKA, PKC), AMP Kinase (AMPK) and glycogen synthase kinase-3 (GSK3) affect their activity in a ligand-dependent or -independent manner. The effects of phosphorylation depend on the cellular context, receptor subtype and residue metabolized which can be manifested at several steps in the PPAR activation sequence including ligand affinity, DNA binding, coactivator recruitment and proteasomal degradation. The review will summarize the known PPAR kinases that directly act on these receptors, the sites affected and the result of this modification on receptor activity.
A simple fibril and lectin model for cyst walls of Entamoeba and perhaps Giardia

Cyst walls of Entamoeba and Giardia protect them from environmental insults, stomach acids, and intestinal proteases. Each cyst wall contains a sugar homopolymer: chitin in Entamoeba and a unique N-acetylgalactosamine (GalNAc) homopolymer in Giardia. Entamoeba cyst wall proteins include Jacob lectins (carbohydrate-binding proteins) that crosslink chitin, chitinases that degrade chitin, and Jessie lectins that make walls impermeable. Giardia cyst wall proteins are also lectins that bind fibrils of the GalNAc homopolymer. Although many of the details remain to be determined for the cyst wall of Giardia, current data suggest a relatively simple fibril and lectin model for the Entamoeba cyst wall.
Initial stages of sperm penetration into the egg of Fundulus heteroclitus

Very little information is available about the morphological details of sperm-egg fusion in teleosts. The acrosomeless teleost sperm gains access to the egg cytoplasm through a small opening (the micropyle) in the egg envelope (the chorion). Identification of the micropyle, therefore, permits one to localize the sperm entry site and to use the electron microscope to study the details of sperm-egg fusion under normal monospermic conditions. In this study freshly stripped eggs of Fundulus heteroclitus were inseminated with sperm of the same species and exposed to fixative at intervals varying from 1 second to 15 minutes after insemination. The scanning electron microscope was used to observe morphological aspects of the initial stages of fertilization.
A Karnaugh mapping technique for the modeling of single phase multi string multi level inverter

The main objective of this paper is to study a seven level multi string converter topology for distributed energy resources based DC-AC conversion system. This paper proposes the Karnaugh mapping technique (which was rarely used in power electronic converters) for modeling the multi string seven level converter. The proposed method can also be extended to `n' level converter. This paper also proposes the double Fourier series analysis to determine the expressions for modulation signals with particular reference to seven level design. This paper also compares the switching losses between cascaded and multi string multi-level inverters. The studied multi string inverter topology offers strong advantages such as less switching losses, improved output voltage waveforms, lower EMI and lower THD.