cssi/SciSciGPT-SciSciNet huggingface dataset:
Assembly of Acanthamoeba Myosin-II Minifilaments. Definition of C-terminal Residues Required to Form Coiled-coils, Dimers, and Octamers

Acanthamoeba myosin-II forms bipolar octamers by three successive steps of dimerization of the C-terminal, coiled-coil tail. In this study, we generated N-terminal and C-terminal truncation constructs and point mutants of the Acanthamoeba myosin-II tail to delineate the structural requirements for assembly of bipolar mini-filaments. By the use of light-scattering, CD spectroscopy, analytical ultracentrifugation, and tryptophan fluorescence experiments, we determined that: (1) the C-terminal 14 heptad repeats plus most of the tailpiece (residues 1381–1509) are required to form antiparallel dimers of coiled-coils; (2) amino acid residues within heptads 23–32 (residues 1254–1325) are required to form tetramers; (3) the C-terminal 32 heptad repeats suffice to assemble octameric minifilaments; (4) A1378 is outside of the interaction interface; (5) the mutation L1475W inhibits dimerization; and (6) F1443 is involved in the dimerization interface but is exposed to the solvent. We propose that the tailpiece (residues 1483–1509) interacts with two heptads (13 and 14, residues 1381–1393), which are important for dimerization and coiled-coil formation. These results support a model in which hydrophobic as well as electrostatic interactions control the register between myosin-II coiled-coils and guide sequential steps of dimerization that generate stable, octameric mini-filaments.
SAR image construction from periodically gapped phase-history data

It is known that high-resolution synthetic aperture radar (SAR) imaging can be cast as a spectral analysis problem, and consequently a number of sophisticated spectral estimation methods have been applied to SAR imaging. These method include the classical Capon method and the closely related Amplitude and Phase Estimation (APES) algorithm. In this paper, we show how Capon and APES can be extended to deal with spectral analysis of periodically gapped (PG) data, i.e. data where samples are missing in a periodic fashion. This problem is highly relevant for SAR imaging with angular diversity since in that case the measured phase-history data matrix contains missing columns. Our extension of Capon and APES is based on a transform that maps a one-dimensional (1D) periodically gapped time-series into a uniformly sampled two-dimensional (2D) data set. We show that the stationarity properties of the 1D signal are left unchanged by the transformation, and as a result the conventional 2D Capon and APES methods can be applied to the transformed data. An associated inverse transform is used to extract the 1D spectral estimate from the 2D one. The new method is computationally and conceptually non-intricate and it does not involve any interpolation of the missing data. Despite its striking simplicity, numerical results indicate that the new method can be a promising tool for SAR imaging with angular diversity as well as for time-series analysis. In SAR applications, the new method may be particularly suitable for accurate imaging of a small region of interest.
Dehydroepiandrosterone sulfate improves memory in aging mice

Middle-aged (18 month old) and old (24 month old) mice showed poorer retention of footshock active avoidance training (FAAT) than young mice (2 month old). Immediate post-training subcutaneous injection of dehydroepiandrosterone sulfate (DHEAS) improved retention of FAAT in middle-aged and old mice to the high levels observed in young mice. DHEAS, a major naturally occurring adrenal steroid that decreases in blood serum with age, could be rate-limiting in achievement of retention of learning.
Peddling Pedagogies: The Winners and Losers of a Standardized Testing Economy

This review compares the ethnographic research of Jessica Zacher Pandya’s Overtested: How High-Stakes Accountability Fails English Language Learners with the programmatic prescriptions of Yvette Jackson’s Pedagogy of Confidence. Both texts are concerned with the impact of standardized testing on urban students, but the focus of each book is quite different in terms of public policy on education and the way teacher roles are construed.
Low-Btu gas mixtures—I. Methane oxidation rates for a wide range of equivalence ratios☆

Abstract We present estimates for the effective oxidation rates of methane over a wide range of equivalence ratios using Ar as primary diluent and CO or H 2 O as additives. The rate of disappearance of methane has been monitored in a fuel-rich CH 4 O 2 Ar mixture by direct measurements of the change in transmission for He-Ne laser radiation at 3.392 μ behind reflected shock waves. The rate of formation of water with time has been obtained in independent absolute i.r. emission measurements near 6.75 μ on stoichiometric CH 4 O 2 Ar mixtures with and without added water. We have found empirically that a number of data correlations may be used and that the overall rates of disappearance of CH 4 and of formation of H 2 O were the same during the post-induction period behind reflected shock waves. The rates of concentration changes with time to which we refer are average rates observed during the post-induction periods. The temperatures ( T max ) for which the oxygen-atom concentrations are a relative maximum were found to be close to the arithmetic means between the initial temperatures ( T 5 ) behind reflected shock fronts and the final equilibrium temperatures. The numerical values found for the correlation parameters as functions of the temperature during the post-induction oxidation are not sensitive to the prior admixture of CO or H 2 O but vary with mixture ratio. The overall methane conversion rates are directly useful in defining burner designs for the utilization of highly diluted mixtures (i.e. low-Btu gas systems) containing primarily CH 4 . Our results are not applicable to low-Btu gas mixtures containing such reactive species as H 2 or NH 3 .
Medical student career choice: a conceptualization.

Abstract A model is proposed which conceives the making of career choice decisions by medical students as a process in which the student seeks an optimum match between the career alternatives open to him and his own preferences and life circumstances. The elements conceptualized in this process are the personal characteristics domain, the cognitive lens, the medical school environment, and the choice domain. These elements are given broad and fairly open-ended conceptualizations in order to provide a generalized framework within which to unify and guide respectively past and future empirical research. To illustrate the utility of the model in this respect, a general strategy of theory construction is first described and then demonstrated using the model as a cohesive framework. It is suggested that several heretofore distinct areas of investigation can be fruitfully brought together by the model in ways which can both increase our understanding of medical students' career choices and point the way to future research having theoretical and practical import.
Quantum control and a novel atom-light quantum interface

The emerging field of quantum engineering seeks to design and construct quantum devices for use in technological applications. To do so, one must learn to prepare a physical system in a well defined quantum state, drive it though a specified evolution, and access its final state through measurement. Historically, some of the most successful laboratory platforms with which to explore these challenges have originated in the field of quantum optics. This work reviews some of the recent advances in single- and many atom quantum control at the College of Optical Science, and their integration into a novel atom-light quantum interface.
Infrared characterization of hafnium oxide grown by atomic layer deposition using ozone as the oxygen precursor

HfO2 growth on H-terminated Si surfaces by atomic layer deposition (ALD) is studied with in situ Fourier transform infrared spectroscopy and ex situ Rutherford backscattering, using tetrakis-(ethyl-methyl-amino) hafnium and ozone as the hafnium and oxygen precursors, and compared to water-vapor-based ALD growth. The reaction pathways are different for the two oxygen precursors, leading to a lower growth rate for ozone (∼0.05nm∕cycle) than for water-based growth and to incorporation of different impurities in the HfO2 film. Furthermore, interfacial SiO2 is readily formed with ozone at the growth temperature (∼100°C), in contrast to water-based HfO2 growth.
Seismic Anisotropy in the Lower Oceanic Crust

HESS1 suggested that upper mantle compressional wave velocities near the Mendocino and Molokai fracture zones of the Pacific vary with azimuth and this anisotropy is the result of preferred mineral orientation. Recent seismic refraction evidence indicates that in many regions the Earth's upper mantle is anisotropic2–4 and the observed Anisotropy in the upper mantle correlates well with laboratory studies of velocity Anisotropy in dunites and peridotites5,6. Although anisotropy complicates seismic refraction investigations its importance cannot be overestimated; it places severe limitations on probable upper mantle compositions and provides a means of estimating the stress fields which existed during the formation of preferred mineral orientation in the upper mantle.
Spontaneous CP violation in SU(5) and proton decay

A minimal model of spontaneous CP violation and natural flavor conservation is presented in the context of the standard SU(5) grand unification. Some of its main features are analyzed, with special emphasis on implications for proton decay. A salient feature of the model is the fact that all vector-gauge-boson interactions are CP conserving. As a result of the gauge hierarchy, the interactions of the baryon-number-violating color triplets of Higgs bosons are also CP conserving, leading to no CP violation in proton decay.
Cognitive deficits in long-term survivors of childhood medulloblastoma and other noncortical tumors: Age-dependent effects of whole brain radiation

Twenty-four children, aged 1.5–20 yr at diagnosis, with noncortical brain tumors, primarily medulloblastoma, have been followed for 3–4 yr for intellectual status. All the children received craniospinal irradiation, and 19 of 24 received chemotherapy as well. For the group as a whole, Full Scale IQ fell from 104 at baseline to 91 at final follow-up. Children younger than 7 yr at diagnosis showed a significant decrease in IQ as early as year 1, and all changes from baseline to years 3 and 4 were significant. In contrast, children older than 7 yr at diagnosis did not show a significant IQ change from baseline to year 3 or 4. The Spearman correlation coefficient between IQ change and age at diagnosis from baseline to year 4 was 0.57 (P=0.003). This study supports the hypothesis that children treated with whole brain radiation at a younger age have more severe cognitive impairment than those treated at a later age. Limitations in sample size and duration of observations do not permit us to identify whether a true plateau occurs 2–4 yr after irradiation versus a continued progressive decline in intellectual performance. Moreover, we cannot at this time distinguish between a true dementing process versus failure to acquire new cognitive skills at a rate comparable to age-matched peers.
Transport of bedload as ripples during an ebb current

Abstract A large instrumented tripod was used during a period of relatively strong ebb current in Puget Sound, to measure simultaneously the currents within 1.5 m of the sea bed and the changing ripple configuration of a sandy bottom. Measurement of the heights and migration rates of the ripples on time-lapse stereo photographs made it possible to calculate the amount of sediment moved. From the measured velocity profiles, the shear velocity, U∗ , and the fluid power expended on the bed, ρU∗ 3 , were determined. These measurements of mass transport are compared with the values predicted by several existing bedload transport theories. Einstein's (1950) and Yalin's (1963) equations predict values with the appropriate trend of the curve of mass transport vs. U∗ , but their values are too large, because of a difference in the boundary shear stress measurement used in the comparison. Bagnold (1963) relates immersed weight of transported sediment to fluid power by a proportionality coefficient, K, which supposedly reaches a constant maximum value for any system. Our measurements indicate that K increased exponentially with the growth of ripples, which in turn were related to the flow conditions. Bagnold's basic formulation has been modified with respect to a variable K, and when compared with flume data, the mass transport of sediment was adequately predicted. It appears that K does not reach a constant value in most marine environments but is related to the sediment characteristics, the shear stress, and the turbulence of the flow.
Quantum yield distributions in the IR photolysis of 2-bromoethanol in solid argon

Abstract Quantum yields for the photoisomerization of 2-bromoethanol in Ar after excitation of the OH stretch range from zero to near 1. The distribution of quantum yields is broader than the other 2-haloethanols or HONO. The quantum yield distribution is approximately the inverse Laplace transform of the decay of the reagent under photolysis. Initial quantum yields are useful for comparing the relative rates of these reactions. Distributions in quantum yields reflect distributions in the rates of the elementary photophysical processes.
PCNS: A novel protocadherin required for cranial neural crest migration and somite morphogenesis in Xenopus

Protocadherins (Pcdhs), a major subfamily of cadherins, play an important role in specific intercellular interactions in development. These molecules are characterized by their unique extracellular domain (EC) with more than 5 cadherin-like repeats, a transmembrane domain (TM) and a variable cytoplasmic domain. PCNS (Protocadherin in Neural crest and Somites), a novel Pcdh in Xenopus, is initially expressed in the mesoderm during gastrulation, followed by expression in the cranial neural crest (CNC) and somites. PCNS has 65% amino acid identity to Xenopus paraxial protocadherin (PAPC) and 42-49% amino acid identity to Pcdh 8 in human, mouse, and zebrafish genomes. Overexpression of PCNS resulted in gastrulation failure but conferred little if any specific adhesion on ectodermal cells. Loss of function accomplished independently with two non-overlapping antisense morpholino oligonucleotides resulted in failure of CNC migration, leading to severe defects in the craniofacial skeleton. Somites and axial muscles also failed to undergo normal morphogenesis in these embryos. Thus, PCNS has essential functions in these two important developmental processes in Xenopus.
TH‐C‐BRA‐09: Robust 3D Lung Tumor Tracking Using Maximum Likelihood Estimation

Purpose: To develop a robust 3D lungtumor tracking method based on a single x‐ray projection using maximum likelihood estimation. Methods: 4DCT images at different phases are registered to yield motion vector fields and a PCA based lung motion model is built. An acquired CBCT projection is compared with the simulated projections under different metrics to yield the correct PCA coefficients and hence the corresponding motion vector fields, which can be used to derive the 3D tumor location at this projection. The metrics we considered include normalized cross correlation and normalized mutual information between the gradient images of the acquired CBCT and that of the simulated 4DCT projection, and the position of diaphragm. A maximum likelihood estimation method is developed to combine the tracking results from all the metrics and integrate the constraints regarding tumor motion smoothness and wave form, leading to robust tumor locations. The method is tested on real patient data. Results: It is found that normalized cross correlation, normalized mutual information, and diaphragm location can be used to determine the PCA coefficients and the tumor position, although the efficacy of any single metric depends on the gantry angles and breathing phases. However, with the combination of different metrics, the tumor tracking accuracy is greatly improved. The resulting mean 3D error is found to be 1.3mm. Conclusions: A robust 3D tumor tracking method is developed based on maximum likelihood estimation to derive tumor location corresponding to an x‐ray projection for lungcancer patient. This work is supported by Varian Medical Systems through a Master Research Agreement.
Foreign Language Teachers' Attitudes: A Strategy for Exploration and Change*

In our search for the ‘right’ method or approach, we often forget that the teacher's own growth and development are of ultimate importance. This article presents a rationale for ‘humanizing’ teacher inservice education and one values clarification technique–an attitude survey–used to assist teachers in their growth. This survey was developed to aid teachers in exploring their own attitudes and beliefs about foreign language learning and teaching. The attitude survey is comprised of fifty-three questions which deal with a variety of ideas on the philosophy of language teaching, techniques, innovations, learning behaviors, etc. A scoring section and an explanation of the scoring procedures and their meanings are included, the function of which is to provide for discussion of values as related to the teaching profession.
Leaders, managers, and the organization of township and village enterprises in China

Abstract The managerial contractual form in China's township and village enterprise (TVE) sector has evolved rapidly during the past 10 years. Our paper uses descriptive data and a theoretical model to demonstrate that these changes may be occurring in response to the rapid development of markets in transitional rural China. We econometrically test the model's main hypotheses, showing that the driving force behind the movement from a leader-run fixed-wage contract to a fixed-payment contract with better incentives for the manager is the relative value of non-marketed inputs owned by local leaders and firm managers. Firm technical structure and local market setting also plays a role in the determination of firm contractual form.
Differentiation of Mesozoic basalts of the Hartford basin, Connecticut

The Talcott, oldest of the three basalts in the Mesozoic Hartford basin of Connecticut, contains abundant euhedral olivine and plagioclase phenocrysts and less common rounded augite-plagioclase aggregates and orthopyroxene phenocrysts rimmed by augite and olivine. The orthopyroxene, which has a remarkably constant composition (En 84 ) and is Cr-rich, is believed to be a refractory residue from an upper-mantle source region. The Holyoke basalt, the middle unit, is essentially aphyric, with only minor plagioclase and olivine phenocrysts. The Hampden, youngest of the three basalts, contains abundant plagioclase and minor olivine and augite phenocrysts. Materials-balance calculations using phenocryst compositions from the Talcott basalt indicate that the Holyoke can be derived from a Talcott magma by addition of 7.8% orthopyroxene and removal of 7.9% olivine, 15% clinopyroxene, and 13.3% plagioclase. The Hampden basalt cannot be derived from a Holyoke magma by any reasonable fractionation scheme, but it can be derived from a Talcott magma by removal of 4.4% olivine, 12.0% clinopyroxene, and 14.3% plagioclase. One-atmosphere melting experiments under controlled oxygen fugacities indicate successively lower liquidus temperatures for Talcott, Holyoke, and Hampden basalts. Both the Talcott and the Holyoke have olivine and plagioclase on the liquidus simultaneously, with augite and pigeonite appearing ∼15 °C below the liquidus. The Hampden has plagioclase alone on the liquidus; olivine and augite appear only 5 °C below the liquidus. Orthopyroxene is not present in the low-pressure experiments but is thought to have been stable on the liquidus at depths corresponding to pressures exceeding 8 kbar. Assimilation of orthopyroxene and crystallization of other phases necessary to produce the Holyoke basalt from a Talcott magma must have taken place at depth; however, because the low-pressure phases obtained in the experiments are those required to produce the Hampden from the Talcott magma, this fractionation likely occurred in a near-surface magma chamber.
A network model for the optic flow computation of the MST neurons

Abstract A simple and biologically plausible model is proposed to simulate the optic flow computation taking place in the medial superior temporal (MST) area of the visual cortex in the primates' brain. The model is a neural network composed of multiple competitive learning layers. The input layer of the network simulates the MT neurons that selectively respond to the visual stimuli with different local velocities and send strong synaptic projections to the MST neurons. The middle and output layers of the network simulate the MST neurons which selectively respond to different types of optic flow motion patterns (planar, circular, radial and spiral motions), as well as different locations of the center of motion (COM). The simulation results show that the behaviours of the output nodes of the networks resemble closely the known responsive properties of the MST neurons found neurophysiologically, such as the existence of three types of MST neurons which respond, respectively, to one, two, or three types of input motion patterns, and the response selectivity for the location of COM. Experimental results with real image data show that the network model is able to detect the location of the COM in the optic flow field.
End-of-Life Decisions Using Product Life Cycle Information

The concept of disassembly-to-order (DTO) has recently become popular. The goal of DTO is to determine the optimum number of end-of-life (EOL) products to be disassembled in order to fulfill the demand for components and materials such that some desired criteria of the system are satisfied. However, the outcome of this problem is fraught with errors. This is due to the unpredictable circumstances of the EOL products which stem from many sources such as the operating environment, different usage patterns and customers upgrades. If one could get advanced information about the status of the products, it could prove to be quite invaluable in making EOL management decisions. Advanced product information consists of two types of data, viz., static and dynamic. The static data consists of the product name, the brand name, the model type, etc. The dynamic data consists of cumulative data covering the circumstances to which the product was subjected to during its useful life. Capturing these data has become an important goal of many manufacturers. Numerous technological advances and the availability of various monitoring devices, embedded in products, offer us with many product monitoring and data collection alternatives. In this paper, an integer program is developed to model and solve the DTO problem that utilizes the captured data from EOL products. A numerical example is considered to illustrate the use of this methodology.Copyright © 2008 by ASME
Callionymus russelli, a new species of callionymid fish from Queensland, Australia

A new species of dragonet, Callionymus russelli, is described from Queensland waters. Callionymus russelli may be distinguished from the closely related species, C. punctatus, by the colour patterns of the first dorsal fins, by the smaller size, by the snout length being the same or slightly less than the eye length, by the preopercular spine being slightly longer than the eye, and by the caudal fin length in the female being only slightly longer than the head, and rarely twice the length of the head in the male. From the other Queensland species of Callionymus, its small size will eliminate it from being confused with the majority of species. It differs from C. calliste and C. macdonaldi, the only two of similar size, by having a somewhat pointed snout, different dorsal fin colour patterns, and the distinct body markings of numerous light or dark brown vertical streaks along the sides of the body in males. A revised key to the Australian dragonet species within the genus Callionymus is given.
Rapid and sensitive gas chromatographic quantitation of morphine codeine and O6-acetylmorphine in illicit heroin using an electron capture detector.

Abstract Morphine, codeine and O6-acetylmorphine are reacted with heptafluorobutyric anhydride, rendering them suitable for electron capture detection and quantitation. The fluorinated derivatives are extracted from an acetonitrile—sodium bicarbonate solution into light petroleum in a rapid one-step extraction procedure. The derivatives are chromatographed on a stationary phase of 3% OV-17 on Gas-Chrom Q. Morphine, codeine and O6-acetylmorphine can be readily quantitated in heroin at levels as low as 0.001%, 0.01% and 0.01% respectively. Reproducibility, linearity and recovery studies are described.
Heterozygosity for Premature Termination Codon Mutations in LAMB3 in Siblings with Non-Lethal Junctional Epidermolysis Bullosa

Junctional epidermolysis bullosa (JEB; OMIM nos. 226650 and 226700) is clinically characterized by fragility of the skin and various extracutaneous epithelia (Fine et al. 1991;Pulkkinen et al. 1999). Diagnostic electron microscopy and immunoepitope mapping of the JEB patients' skin have revealed that tissue separation occurs within the lamina lucida, associated with abnormalities in hemidesmosomes, critical attachment structures at the dermal–epidermal basement membrane zone (Tidman & Eady 1986;Verrando et al. 1991). Clinically, JEB has been divided into the lethal, Herlitz variant (H-JEB), which results in early demise, and nonlethal forms characterized by protracted blistering without compromising the lifespan of the affected individuals.
Triterpenoids of Amsonia grandiflora

Abstract Stems and leaves of Amsonia grandiflora yielded lupeol β-hydroxyoctadecanoate, betulinic acid, oleanolic acid, lupeol, lupeol acetate and 1-O-methyl-myo-inositol.
Absolubilization of Styrene and Isoprene in Cetyltrimethylammonium Bromide Admicelle on Precipitated Silica

The adsolubilization of styrene, isoprene, and mixtures of styrene and isoprene into cetyltrimethylammonium bromide (CTAB) bilayers (admicelles) on precipitated silica is investigated. The results show that the styrene adsolubilization constant is nearly unchanged with increasing styrene equilibrium concentration in the aqueous phase, while the isoprene adsolubilization constant increases with increasing isoprene partial pressure. The adsolubilization constants suggest that styrene adsolubilizes into both the palisade layer and the core of the admicelle, while isoprene adsolubilizes into the palisade layer. In the co-monomer system styrene adsolubilization is slightly increased in the presence of isoprene but isoprene adsolubilization is significantly enhanced in the presence of styrene; however, the adsolubilization isotherms of both monomers have increasing slopes in the co-monomer system and show that there is a synergistic effect, possibly due to swelling of the admicelle due to the addition of adsolu...
Quantitative determination of clenbuterol, salbutamol and tulobuterol enantiomers by capillary electrophoresis.

Enantiomers of clenbuterol, salbutamol and tulobuterol were directly separated and quantitated from a spiked sample by capillary electrophoresis (CE) using sulfated β-cyclodextrin (SCD) as chiral selector and phosphate as running buffer. The SCD and buffer concentration, pH and field strength were the parameters studied to optimize the separation. Optimal separation was obtained using 50 mM of phosphate monobasic at pH = 2.24, 0.25% (w/w) of sulfated cyclodextrin and a field strength of 10 kV, with 20 min total time analysis. Comparison between two different injection modes (hydrodynamic and electrokinetic) was made. In the hydrodynamic mode, repeatability (expressed as relative standard deviation, RSD) was less than 1.2% for migration times for all the analyte peaks and less than 2% for peak area percentages. With respect to reproducibility, RSD was less than 3.8% for migration time and less than 3% for peak area percentages. Calibration curves were set up for two different sample concentration ranges (1 to 10 μg mL–1 and 160– 800 ng mL–1, of each of the racemates studied). Although the electrokinetic injection mode for an aqueous sample appeared to suffer from some enantiodiscrimination, calibration curves were linear in the range between 1 and 10 ng mL–1 with regression coefficients ranging from 0.9996 to 0.9952. As in the case of hydrodynamic injection, the method was tested with a spiked sample.
Online credibility and community among blog users

This study is based on a secondary analysis of data from a survey of U.S. adults related to informational media use, trust, and community engagement. The authors were interested in determining if the act of contributing to online information sources (blogs, in this case) was correlated with higher expressions of trust in “alternative” or citizen-journalism sites. While familiarity with these sites has often been shown to correlate with higher trust measures, isolating participatory behavior from reading/use behavior is a particular question that has not been much addressed in the literature. Several survey responses related to online behaviors and attitudes were examined, and contributor users were found to be more likely to rate alternative media sites (with user-contributed content) as credible than other users. This effect was consistent even when controlling for demographic factors or otherwise generally advanced online information use. Content contributor users were also found to score slightly higher on measures of off-line social capital. This conclusion suggests an area for future research into the norms and motivations behind the development of collaborative information resources, and better analysis of the role of trust or credibility in explaining why some types of online resources (wikis, blogs, digital libraries, etc.) succeed and flourish, while others do not.
Multi-wavelength VLA and Spacecraft Observations of Evolving Coronal Structures Outside Flares

Multi-wavelength Very Large Array (VLA), SOHO and RHESSI observations have been used to study the three- dimensional structure of evolving coronal loops and related signatures of impulsive and long-lasting energy release above active regions. Here, we discuss recent multiwavelength observations of an impulsive hard X-ray burst that was preceded by gradual changes in the structure of an extended coronal loop connecting the active region to one located on the other side of the solar equator, suggesting pre-burst magnetic evolution at different spatial scales. Changes in the 6 and 20 cm brightness temperature were also detected from the opposite footpoint region suggesting some sort of magnetic connectvity across the solar equator. To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
Notch-1 and Notch-4 biomarker expression in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) demonstrates lack of expression of hormone receptors and human epidermal growth factor receptor. However, there is no targeted therapy for TNBC. The authors analyzed 29 TNBC cases for Notch-1 and Notch-4 biomarker expression and subcellular location, Ki67 proliferation rate, and relevant clinical/survival data. Results demonstrated an unfavorable Ki67 rate in 90% of cases, Notch-1 expression in tumor and endothelial cells in 100% of cases, and Notch-4 expression in tumor cells in 73% of cases and endothelial cells in 100% of cases. Additionally, subcellular localization of Notch-1 and Notch-4 was predominantly nuclear and cytoplasmic. In conclusion, (a) the majority of TNBCs are high-grade infiltrating ductal carcinomas with high Ki67 proliferation rate and (b) both Notch-1 and Notch-4 receptors are overexpressed in tumor and vascular endothelial cells with subcellular localization different from that of hormone-positive breast cancer. Targeting Notch signaling with ga...
A class of multi-factor designs for test versus control comparisons

Type S designs for test versus control comparisons have been provided by several researchers over the last decade or so. A generalization of these designs in order to cover the case of multi-factor experiments each of which has a control level has been considered in a previous paper under the name of S-PB designs. A wide class of type S-PB designs for multi-factor experiments is provided in this paper. Some general series are also provided.
Apoptosis and DNA fragmentation as induced by tertiary butylhydroperoxide in the brain

In this study, the effect of intracerebroventricular administration of the free radical generator, tertiary butylhydroperoxide, on DNA, was quantitated. Previous studies had established DNA as a very important site of free radical attack. The purpose of the study was to detect whether DNA was one of the primary targets of the toxin as well as to detect any apoptosis that may have been induced by the toxin. The DNA fragmentation assay clearly showed DNA damage within 20 min of administration of 109.7 mg/kg t-BuOOH almost in all brain regions in both 2-month and 8-month-old C57BL/6 mice. In Situ Apoptosis Detection assay, where brain sections were stained with Apoptag, demonstrated that t-BuOOH induces apoptosis in many brain regions. Electron microscopy was done to show nuclear damage and DNA fragments appearing in the cytoplasm. Cresyl violet staining was done to show that while low dose (21.9 mg/kg) t-BuOOH induces apoptosis, it may also induce necrosis in other cells of the same brain region. Thus, from this study we can conclude that DNA may be one of the primary target sites of free radical attack in the brain, and results in both necrosis and apoptosis. This can have a profound effect on neurodegeneration.
Using electrical and optical tweezers to facilitate studies of molecular motors

Dielectrophoresis was used to stretch and suspend actin filaments across a trench etched between two electrodes patterned on a glass slide. Optical tweezers were used to bring a motor protein-coated bead into close proximity to a pre-selected, suspended actin filament, facilitating the attachment of the myosin-coated bead to the filament. The clearance beneath the filament allowed the bead to move freely along and around its filamentous track, unhindered by solid surfaces. Using defocused images, the three-dimensional position of the bead was tracked as a function of time to obtain its trajectory. Experiments were carried out with myosin V and myosin X. Both motor proteins followed left-handed helical paths with the myosin X motor exhibiting a shorter pitch than the myosin V. The combined use of electrostatic and optical tweezers facilitates the preparation of motility assays with suspended tracks. Variants of this technique will enable higher complexity experiments in vitro to better understand the behavior of motors in cells.
Design Optimization of a Portable Thermophoretic Precipitator Nanoparticle Sampler

Researchers at the National Institute for Occupational Safety and Health (NIOSH) are developing methods for characterizing diesel particulate matter in mines. Introduction of novel engine and exhaust aftertreatment technologies in underground mines is changing the nature of diesel emissions, and metrics alternative to the traditional mass-based measurements are being investigated with respect to their ability to capture changes in the properties of diesel aerosols. The emphasis is given to metrics based on measurement of number and surface area concentrations, but analysis of collected particles using electron microscopy (EM) is also employed for detailed particle characterization. To collect samples for EM analysis at remote workplaces, including mining and manufacturing facilities, NIOSH is developing portable particle samplers capable of collecting airborne nano-scale particles. This paper describes the design, construction, and testing of a prototype thermophoretic precipitator (TP) particle sampler o...
A role for free phosphinidenes in the reaction of magnesium and sterically encumbered ArPCl2 in solution at room temperature

Abstract The reduction of ArPCl 2 (Ar=2,6-Trip 2 C 6 H 3 , 2,6-Mes 2 C 6 H 3 , 2,6-(2,6-Me 2 C 6 H 3 ) 2 C 6 H 3 , or 2,4,6- t Bu 3 C 6 H 3 ) by various forms of activated magnesium have been examined and compared with previously reported reductions using unactivated magnesium. The current reactions are more rapid and give rise to products that are reminiscent of products obtained by irradiation of phosphanylidene-σ 4 -phosphoranes ArPPMe 3 bearing the same Ar groups. The correlation in product distributions suggests the involvement of phosphinidenes in the reduction of aryldichlorophosphines by activated magnesium.
How Presentation Flaws Affect Perceived Site Quality, Trust, and Intention to Purchase from an Online Store

Although there has been a great deal of research on impression formation, little application of that research has been made to electronic commerce. A research model was constructed that hypothesized errors, poor style, and incompleteness to be inversely related to the users' level of perceived quality of an online store. Further, this perceived quality of the online store's Web site would be directly related to users' trust in the store and, ultimately, to users' intentions to purchase from the store. An experimental study with 272 undergraduate and graduate student volunteers supported all the hypotheses. In addition, it was found that the relationship between the factors and perceived quality was mediated by the perception of the flaws. The perception of flaws rather than the actual flaws influenced users' perception of quality. Supplemental analysis also seemed to indicate a pattern of diminishing effects with each subsequent flaw.
Open cholecystectomy. A contemporary analysis of 42,474 patients

OBJECTIVE: This study evaluated, in a large, heterogeneous population, the outcome of open cholecystectomy as it is currently practiced. SUMMARY BACKGROUND AND DATA: Although cholecystectomy has been the gold standard of treatment for cholelithiasis for more than 100 years, it has recently been challenged by the introduction of several new modalities including laparoscopic cholecystectomy. Efforts to define the role of these alternative treatments have been hampered by the lack of contemporary data regarding open cholecystectomy. METHODS: A population-based study was performed examining all open cholecystectomies performed by surgeons in an eastern and western state during a recent 12-month period. Data compiled consisted of a computerized analysis of Uniformed Billing (UB-82) discharge analysis information from all non-Veterans Administration (VA), acute care hospitals in California (Office of Statewide Planning and Development [OSHPD]) and in Maryland (Health Services Cost Review Commission [HSCRC]) between January 1, 1989, and December 31, 1989. This data base was supplemented with a 5% random sample of Medicare UB-82 data from patients who were discharged between October 1, 1988, and September 30, 1989. Patients undergoing cholecystectomy were identified based on diagnosis-related groups (DRG-197 and DRG-198), and then classified by Principal Diagnosis and divided into three clinically homogeneous subgroups: acute cholecystitis, chronic cholecystitis, and complicated cholecystitis. RESULTS: A total of 42,474 patients were analyzed, which represents approximately 8% of all patients undergoing cholecystectomy in the United States in any recent 12-month period. The overall mortality rate was 0.17% and the incidence rate of bile duct injuries was approximately 0.2%. The mortality rate was 0.03% in patients younger than 65 years of age and 0.5% in those older than 65 years of age. Mortality rate, length of hospital stay, and charges were all significantly correlated (p < 0.001) with age, admission status (elective, urgent, or emergent), and disease status. CONCLUSIONS: These data indicate that open cholecystectomy currently is a very safe, effective treatment for cholelithiasis and is being performed with near zero mortality. The ultimate role of laparoscopic cholecystectomy needs to be defined in the context of current and contemporary data regarding open cholecystectomy.
Neurotrophin receptor mRNA expression defines distinct populations of neurons in rat dorsal root ganglia

The biological actions of neurotrophins are mediated by specific neurotrophin receptor tyrosine kinases (Trks). A low-affinity nerve growth factor (NGF) receptor, p75, appears to modulate sensitivity to neurotrophins in some neuronal populations. It has been recently demonstrated that genes encoding members of the Trk family are expressed in distinct patterns in the dorsal root ganglia (DRG; Mu et al. [1993] (J. Neurosci. 13:4029- 4041). However, the extent to which different neurotrophin receptor genes are coexpressed by individual DRG neurons is unknown. The question of coexpression is important since the expression of more than one member of the trk family by DRG neurons would suggest the potential for regulation by multiple neurotrophins. To address this question, a combination of isotopic and colorimetric in situ hybridization was performed on rat thoracic DRG using riboprobes specific for trkA, trkB, trkC, and p75. We show here that neurons that express trkA are largely distinct from those that express trkC, although there is a small subpopulation that expresses both of these genes. We also show that there is a distinct population of DRG neurons that expresses trkB and does not coexpress either trkA or trkC. P75 is expressed in almost all neurons that express trkA or trkB, but is coexpressed in only 50% of trkC-expressing neurons. Importantly, p75 is not expressed in DRG neurons independent of trk expression. Finally, a subpopulation of DRG neurons does not express any of the neurotrophin receptor mRNAs. Our results demonstrate that there are distinct populations of DRG neurons that express each member of the neurotrophin receptor tyrosine kinase family. Our findings of extensive colocalization of p75 with trkA and trkB lend support to the idea that p75 is important in mediating the actions of NGF and brain-derived neurotrophic factor on DRG neurons. Interestingly, however, p75 expression is clearly unimportant for a subpopulation of neurons that require neurotrophin-3. The fact that p75 is not expressed in the absence of trkA, trkB, or trkC suggests that the function of p75 is closely related to functions of the known neurotrophin-receptor tyrosine kinases. Finally, our results suggest that a significant percentage of DRG neurons may be regulated by non-neurotrophin neuronal growth factors.
Eriksonian Identity Theory in Counterterrorism

Certain terrorists come from unexpected backgrounds. They give up comfortable lives and opportunities in order to wage jihad. Their existence has puzzled various theorists since they came to light. This article will explain how a theory of psychosocial identity formation created by Erik Erikson and his student James Marcia may explain this phenomenon. It will also explain how Erikson's theoretical legacy has contributed to current attempts at increasing moderation in the Middle East through education. Many of those attempts reflect ideas that are drawn from Eriksonian theory, although they are not typically described in Eriksonian terms. Meanwhile, while some theorists have considered the applications of various aspects of Eriksonian theory, especially negative identity, to terrorism few have focused on radical Islam or evaluated specific biographies against Marcia's additions to the framework. This article is available in Journal of Strategic Security: http://scholarcommons.usf.edu/jss/vol3/iss3/3 27 Eriksonian Identity Theory in Counterterrorism
Engineering, characterization and in vitro efficacy of the major peanut allergens for use in immunotherapy.

Background: Numerous strategies have been proposed for the treatment of peanut allergies, but despite the steady advancement in our understanding of atopic immune responses and the increasing number of deaths each year from peanut anaphylaxis, there is still no safe, effective, specific therapy for the peanut-sensitive individual. Immunotherapy would be safer and more effective if the allergens could be altered to reduce their ability to initiate an allergic reaction without altering their ability to desensitize the allergic patient. Methods: The cDNA clones for three major peanut allergens, Ara h 1, Ara h 2, and Ara h 3, have been cloned and characterized. The IgE-binding epitopes of each of these allergens have been determined and amino acids critical to each epitope identified. Site-directed mutagenesis of the allergen cDNA clones, followed by recombinant production of the modified allergen, provided the reagents necessary to test our hypothesis that hypoallergenic proteins are effective immunotherapeutic reagents for treating peanut-sensitive patients. Modified peanut allergens were subjected to immunoblot analysis using peanut-positive patient sera IgE, T cell proliferation assays, and tested in a murine model of peanut anaphylaxis. Results: In general, the modified allergens were poor competitors for binding of peanut-specific IgE when compared to their wild-type counterpart. The modified allergens demonstrated a greatly reduced IgE-binding capacity when individual patient serum IgE was compared to the binding capacity of the wild-type allergens. In addition, while there was considerable variability between patients, the modified allergens retained the ability to stimulate T cell proliferation. Conclusions: These modified allergen genes and proteins should provide a safe immunotherapeutic agent for the treatment of peanut allergy.
Evaluation of SSMIS Upper Atmosphere Sounding Channels for High-Altitude Data Assimilation

AbstractUpper atmosphere sounding (UAS) channels of the Special Sensor Microwave Imager/Sounder (SSMIS) were assimilated using a high-altitude version of the Navy Global Environmental Model (NAVGEM) in order to investigate their potential for operational forecasting from the surface to the mesospause. UAS radiances were assimilated into NAVGEM using the new Community Radiative Transfer Model (CRTM) that accounts for Zeeman line splitting by geomagnetic fields. UAS radiance data from April 2010 to March 2011 are shown to be in good agreement with coincident temperature measurements from the Sounding of the Atmosphere Using Broadband Emission Radiometry (SABER) instrument that were used to simulate UAS brightness temperatures. Four NAVGEM experiments were performed during July 2010 that assimilated (i) no mesospheric observations, (ii) UAS data only, (iii) SABER and Microwave Limb Sounder (MLS) mesospheric temperatures only, and (iv) SABER, MLS, and UAS data. Zonal mean temperatures and observation − foreca...
Akt negatively regulates translation of the ternary complex factor Elk-1

Cross-talk between signaling pathways plays an important role in regulation of cell growth, differentiation, survival, and death. Here, we show that Akt regulates the Elk-1 transcription factor, independent of its negative regulation of Raf kinases. Using a constitutively active Mek1 to bypass the regulation of Raf by Akt, we find that the Elk-1 and Sap1a proteins are dramatically decreased in the presence of activated Akt. Akt catalytic activity is required. Also, Mek-dependent activation of a TCF (Elk-1/Sap-1a)-dependent c-fos reporter is decreased by activated Akt. Neither the level of Elk-1 mRNA nor the stability of the Elk-1 protein is altered by activated Akt. Instead, the rate of incorporation of labeled methionine into Elk-1 protein is decreased in the presence of Akt. In addition, the level of the Elk-1 protein but not GFP is significantly decreased in the presence of activated Akt, when GFP is expressed from an IRES element in a bicistronic message with Elk-1. We conclude that Akt negatively regulates translation of the Elk-1 mRNA. A coding region determinant that maps within the first 279 nts of the Elk-1 message is necessary and sufficient for Akt-mediated regulation of Elk-1.