cssi/SciSciGPT-SciSciNet huggingface dataset:
Association of short DNA fragments: steady state fluorescence polarization study.

We have studied aggregation/association of monodisperse DNA fragments (ranging from 30–90 base pairs) by steady-state fluorescence polarization of intercalculated ethidium. The method of excitation at different wavelengths in the ethidium absorption spectrum provides information about anisotropic twisting and tumbling mobility of the fragments. We find that end-over-end tumbling rather than axial spinning and internal twisting motions are affected by aggregation/association. The critical concentration for observing the effects of intermolecular interactions is approximately 5 mg DNA/mL at room temperature, independent of fragment length. Association is favored by low temperature and high (> 10 mM) concentration of Mg2+. From temperature-and salt-dependence experiments we infer that the “aggregates” are similar to those observed in a recently discovered DNA sol–gel transition [M. G. Fried and V. A. Bloomfield (1984) Biopolymers23, 2141–2155]. We also discuss possible arrangements of the fragments within the aggregates and their possible relation to formation of DNA liquid crystals.
Dynamic thermal model of PEM fuel cells for MIMO control design

This paper discusses the development of a PEM fuel cell stack model that takes into account dynamic thermal and humidity effects. The outputs of the model are in good agreement with experimental results in literature. This nonlinear MIMO system is linearized and then analyzed by using the Relative Gain Array. The objectives are to understand the coupling between the control loops, and to pair the inputs to the outputs to achieve decentralized SISO control. The control inputs for the RGA are the compressor voltage and coolant flow rate. The performance indices are the net power output and fuel cell temperature. Analysis suggests that in most cases the stack temperature is strongly affected by the coolant flow rate, and the net power output is influenced by the compressor voltage. The coupling of the two loops is caused by the coupling of the heat and mass transfer dynamics during the fuel cell operation. When the fuel cell operates at high temperature and high current demand, the coupling of the two loops attenuates. Therefore, the decentralized SISO control is applicable when the temperature and current are high.Copyright © 2010 by ASME
A simple and efficient system for targeting DNA to the am locus of Neurospora crassa

Abstract We have developed a system of recipient strains and donor plasmids that allows targeting of DNA sequences to the am locus of Neurospora crassa. A recipient strain was constructed that contains the 3' two-thirds of the bacterial Hygromicin B (Hy) phosphotransferase-encoding gene (hph) in single copy downstream from the am structural gene encoding NADP-specific glutamate dehydrogenase. Plasmids have been constructed that contain am, but with the 5' end of hph downstream from am. Resistance to Hy can occur during transformation only if recombination occurs within the region of overlap of the hph sequences from the transforming DNA and of the chromosomal hph sequences. A lacZα. gene with a multiple cloning site has been inserted into the region between the am and hph sequences to facilitate subcloning into the targeting vector. Additionally, unique sites at the junctions of the vector and targeting DNA allow easy removal of vector sequences prior to transformation. A second recipient strain has been constructed that has had the am structural gene deleted. This strain may be used to provide a double selection for homologous integration. Additionally, this strain facilitates replacement of am with heterologous constructs, including constructs that drive transcription of am with different promoters. The insertion of hph downstream from am has no apparent effect on am expression, and the resistance segregates as a Mendelian factor in crosses. Transformation efficiency is reduced two to three orders of magnitude, but interestingly, nearly all of the resistant strains have only a single copy of the transforming DNA.
Effects of streptozotocin-induced diabetes on acetylcholine metabolism in rat brain.

The main objective of this study was to determine whether uncontrolled hyperglycemia, as a consequence of diabetes, altered the metabolism of acetylcholine (ACh) in rat brain. To accomplish this, rats received injections of streptozotocin (STZ, 60 mg/kg, i.v.) or vehicle, and were maintained for up to 7 weeks after the injections. Various indices of ACh metabolism were determined in striatum and hippocampus, two brain regions densely innervated by cholinergic neurons. STZ induced diabetes in 96% of the rats injected, as evidenced by glucose spillage into the urine within 48 hours. Serum glucose levels increased to 326% of control values by 1 week and remained at this level for the duration of the study. The steady-state concentrations of ACh and choline, determined in brain tissue from animals killed by head-focused microwave irradiation, did not differ between the control and STZ-injected groups. However, the synthesis and release of neurotransmitter by striatal slices, measured in vitro, decreased in a time-dependent manner. Although the basal release of ACh was unaltered at 1 week, neurotransmitter release decreased significantly by 21% at 5 weeks and by 26% at 7 weeks. The release of ACh evoked by incubation with 35 mM KCl was inhibited significantly by 20% at all time points studied. ACh synthesis by slices incubated under basal conditions decreased by 13% and 27% at 5- and 7-weeks, respectively, the latter significantly less than controls. Synthesis by striatal slices incubated with 35 mM KCl was inhibited by 17% at 7 weeks. Although the synthesis and release of ACh by hippocampal slices from diabetic animals tended to be less than controls, these alterations were not statistically significant. Investigations into the mechanism(s) mediating the deficit in ACh synthesis exhibited by striatal slices indicated that it did not involve alterations in precursor choline availability, nor could it be attributed to alterations in the activities of the synthetic or hydrolytic enzymes choline acetyltransferase or acetylcholinesterase; rather, the decreased turnover of ACh may be secondary to other STZ-induced, hyperglycemia-mediated neurochemical alterations.
Isolation of an actin polymerization stimulator from bovine thyroid plasma membranes

An actin polymerization stimulator was purified from bovine thyroid plasma membranes by DNase I affinity column chromatography. Although the molecular weight of the protein was about 42,000 (42K) by sodium dodecyl sulfate polyacrylamide gel electrophoresis, it did not comigrate with actin. In the presence of 30 mM KC1, the 42K protein facilitated formation of actin filaments when analyzed by a centrifugation method, accelerated the initial phase of actin polymerization as measured in an Ostwald viscometer and increased the length of filaments as shown by electron microscopy. The 42K protein also accelerated the initial phase of actin polymerization in the presence of 100 mM KC1 and 2 mM MgCl2 but did not affect the final viscosity. The effect of the 42K protein was diminished by 5 uM cytochalasin B or 1 uM cytochalasin D. This 42K protein may anchor actin filaments onto the thyroid plasma membrane.
Gender Differences in Competition: Running Performance in 1,500 Meter Tournaments

Gender differences in outcomes are often explained by gender differences in competitiveness. Using evidence from the outdoor World Championships and Olympics 1,500 meter event, this paper investigates whether gender differences exist in the behavior of runners. Results indicate that there are some gender differences in the competition. Where the gender differences exist, the evidence indicates that there is a difference in the relationship between ability and performance and between peer effects and performance. These results are suggestive of males running more strategically.
Experimental design and data evaluation considerations for comparisons of reference materials

The analysis of reference materials (RMs) can help assess the equivalence of chemical measurement processes. When two or more RMs are available for a given measurand, confidently establishing the equivalence of measurement processes requires the RMs to be capable of yielding equivalent results. Evaluating the degrees of equivalence among RMs that differ in analyte quantity and perhaps matrix composition requires an approach other than that used to assess results for samples of a single material. We have more than a decade of experience with an approach that compares the assigned values of RMs to a simple linear model of the relationship between those values and measurement results ideally made under repeatability conditions. In addition to accessing the metrological equivalence of specific RMs, the equivalence of the value-assignment capabilities of the organizations that issue the RMs can also be accessed. This report summarizes our experience with the design of and analysis of studies using this approach and provides numeric and graphical tools for estimating degrees of equivalence. We divide the required tasks into four steps: (1) design, (2) measurement, (3) definition of a reference function, and (4) estimation of degrees of equivalence. We regard the experimental design and measurement tasks as most critical to the eventual utility of the comparison, since creative mathematics cannot fully compensate for poor planning or erratic measurements.
Planting Date as a Potential Cultural Method for Managing the Rice Water Weevil (Coleoptera: Curculionidae) in Water-Seeded Rice in Southwest Louisiana

Two field studies in Louisiana were conducted in 1991 and 1992 to assess the impact of planting date on the damaging effects of rice water weevil, Lissorhoptrus oryzophilus Kuschel, larvae on rice ( Oryza sativa L.) yield indicators. The data from both years showed that yields of rice planted before mid-April were not reduced by weevil infestation. Early planted rice did not escape damaging populations of rice water weevils but was able to tolerate such infestations without loss of yield, unlike later-planted rice. Economic analysis of the data showed that planting date has a greater impact on yield than does carbofuran treatment. The findings from our study suggested that early rice seeding offered potential as a cultural control tactic in southwest Louisiana to reduce the damaging effects of rice water weevil.
Urban Sewage and Green Meadows: Berlin's Expansion to the South 1870–1920

On May 23, 1908, Frau Treppens, the proprietress of a Gasthaus near the agricultural estate Klein Ziethen contacted the governing council of Steglitz regarding an urgent concern about water damage. Steglitz was five kilometers south of Berlin's southern boundary; Klein Ziethen was twelve kilometers southeast of Steglitz. Writing on the advice of attorney Georg Hillman, Frau Treppens urgently inquired what the council was going to do about the water on her property, which had already caused “enormous damage.” Like many other property owners near Klein Ziethen, she had been battling water in her basement; for some this had been going on for two years. Frau Treppens inquired what steps Steglitz was taking against Rixdorf, another rapidly growing suburb, located on Berlin's southeast perimeter sixteen kilometers from Klein Ziethen. Why was Frau Treppens turning to the officials of Steglitz, and why did she and her attorney assume that Steglitz and Rixdorf bore responsibility for her water-soaked cellar?
Autocorrelation of ultrafast computed tomography coronary calcification scans

Ultrafast computed tomography is currently being investigated for the screening of early asymptomatic heart disease by evidence of the amount of calcium in the coronary arteries. The scanning technique for this test assumes that perfectly contiguous slices can be made by ECG gating and breath holds. Only subjective interpretation of the sequence of images is used to assess the adequacy of axial spatial sampling. This report investigates the autocorrelation matrix of thresholded binary images of heart cross sections in 10 subjects with and without ECG gating problems. In subject with gating problem the average correlation of adjacent slices was statistically reduced compared to subjects without gating problems. The incidence of extremely low or high adjacent slice correlations was greater in the poorly gated group. These preliminary results show that image based information may be used to assess the axial sampling adequacy of UFCT coronary calcification scans.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Abdominovaginal delivery: Modification of the cesarean section operation to facilitate delivery of the impacted head

The abdominovaginal delivery is a modification of the cesarean section operation in the presence of an impacted fetal head, usually after a prolonged second stage of labor with ruptured membranes. With the legs abducted in either the "Whitmore" or the "frog" position, the wedged vertex is gently lifted with the cupped hand into the open transverse uterine incision, thereby reducing injury to the fetal head and the uterus. With the greater use of cesarean section operation and the sharp reduction in rotational and midforceps deliveries, the abdominovaginal procedure has an increasingly important place in our obstetric armamentarium.
Liquid phase epitaxial growth of PbSe on (111) and (100) BaF2

Abstract Optical microscopy, scanning electron microscopy, and x-ray diffraction data are presented for liquid phase epitaxial (LPE) growth of PbSe on (111) and (100) BaF 2 . Lead selenide growth morphology was observed to be highly dependent on LPE growth initiation temperature. {100}-faceted islands oriented to the substrateresulted when growth was initiated below 600° C, while continuous epitaxial layers were consistently produced when growth was initiated between 650 and 670° C. Growth initiated above 690° C, however, yielded two-dimensional polycrystalline layers.
Long-term Structural Health Monitoring of a Multi-girder Steel Composite Bridge Using Strain Data:

This paper presents an approach to use strain data from a multi-girder, composite steel bridge for long-term Structural Health Monitoring (SHM). The bridge being studied is part of a research proje...
The effects of algae species and densities on the population growth of the marine rotifer, Colurella dicentra

Abstract Colurella dicentra clones isolated from bay water in the Mississippi Gulf Coast were cultured with artificial seawater. Experiments were conducted to determine the effects of six algae species ( Nannochloropsis oculata , Tetraselmis chuii , Chaetoceros gracilis , Rhodomonas salina , Isochrysis galbana , and Prorocentrum micans ), six C. gracilis densities, and six N. oculata densities (25,000, 50,000, 100,000, 250,000, 500,000, and 1,000,000 cells ml − 1 ) on C. dicentra population growth. Algae type influenced rotifer production ( p C. gracilis treatment (9120 ± 3351SD) produced the highest number of rotifers followed by N. oculata (5760 ±2232SD). P. micans had the lowest number of rotifers, although not significantly different from numbers in T. chuii , R. salina , and I. galbana treatments ( p > 0.05).The population growth rate ( r ) varied with algae species treatment. The highest values were recorded for C. gracilis treatment (0.22 to 0.26 d − 1 ), followed by N. oculata (0.21 to 0.24 d − 1 ), and the lowest for P. micans (− 0.19 to 0.14 d − 1 ). C. gracilis and N. oculata densities had significant effects ( p C. dicentra population growth. The highest rotifer production was recorded at a C. gracilis density of 100,000 cells ml − 1 , followed by 250,000 cells ml − 1 and 50,000 cells ml − 1 . Algae densities of 500,000 cells ml − 1 and above produced the lowest rotifer numbers. Population growth rate ( r ) varied with C. gracilis densities. The highest values were observed for C. gracilis concentrations of 100,000 cells ml − 1 (0.17 to 0.19 d − 1 ), and the lowest for concentrations of 500,000 cells ml − 1 and above (− 0.19 to 0.09 d − 1 ). The 100,000 cells ml − 1 N. oculata density gave the highest rotifer production followed by 50,000, 250,000, 25,000, and 500,000 cells ml − 1 . Algae densities of 1,000,000 cells ml − 1 produced the lowest rotifer numbers. Population growth rate ( r ) varied with N. oculata densities, with the highest values obtained for algae densities of 100,000 cells ml − 1 (0.35 to 0.40 d − 1 ), and the lowest for concentrations of 1,000,000 cells ml − 1 (0.05 to 0.012 d − 1 ). This is the first report of C. dicentra in Mississippi Coastal waters, and perhaps the smallest marine rotifer species (93 by 49 μm) ever cultured successfully.
Prediction of gas and liquid chromatographic retention indexes of polyhalogenated biphenyls

L'objectif de cette etude est de developper un modele de regression pour prevoir la retention chromatographique des biphenyles halogenes en utilisant des descripteurs emanant des structures moleculaires. L'etude comprend egalement le developpement d'un modele de regression pour la chromatographie utilisant la meme methodologie
AB INITIO THEORETICAL AND MATRIX ISOLATION EXPERIMENTAL STUDIES OF HYDROGEN BONDING : VIBRATIONAL CONSEQUENCES OF PROTON POSITION IN 1:1 COMPLEXES OF HCL AND 4-X-PYRIDINES

Abstract Ab initio calculations at the MP2/6–31 + G(d, p) level have been performed to determined the structures, binding energies, and vibrational spectra of a series of 1:1 HCl:4-X-pyridine complexes with X = H, Ch 3 , NH 2 , OH, F, Cl, CN, CHO, Li, Na, O − and S − . The substituents include both electron donating and electron withdrawing groups which systematically alter the basicity of the pyridine nitrogen. The hydrogen bonds in these complexes span the range of proton positions, including ClH…N hydrogen bonds between neutral molecules, Cl − … + HN hydrogen bonds between ion pairs, and proton-shared Cl…H…N hydrogen bonds. Emphasis is placed on the relationship between proton position and vibrational spectrum, particularly the vibrational bands associated with proton motion.
Fretting corrosion of CoCrMo and Ti6Al4V interfaces.

Abstract Mechanically assisted corrosion (fretting corrosion, tribocorrosion etc.,) of metallic biomaterials is a primary concern for numerous implant applications, particularly in the performance of highly-loaded medical devices. While the basic underlying concepts of fretting corrosion or tribocorrosion and fretting crevice corrosion are well known, there remains a need to develop an integrated systematic method for the analysis of fretting corrosion involving metal-on-metal contacts. Such a method can provide detailed and quantitative information on the processes present and explore variations in surfaces, alloys, voltages, loadings, motion and solution conditions. This study reports on development of a fretting corrosion test system and presents elements of an in-depth theoretical fretting corrosion model that incorporates both the mechanical and the electrochemical aspects of fretting corrosion. To demonstrate the capabilities of the new system and validate the proposed model, experiments were performed to understand the effect of applied normal load on fretting corrosion performance of Ti6Al4V/Ti6Al4V, CoCrMo/Ti6Al4V, and CoCrMo/CoCrMo material couples under potentiostatic conditions with a fixed starting surface roughness. The results of this study show that fretting corrosion is affected by material couples, normal load and the motion conditions at the interface. In particular, fretting currents and coefficient of friction (COF) vary with load and are higher for Ti6Al4V/Ti6Al4V couple reaching 3 mA/cm2 and 0.63 at about 73 MPa nominal contact stress, respectively. Ti6Al4V coupled with CoCrMo displayed lower currents (0.6 mA/cm2) and COF (0.3), and the fretting corrosion behavior was comparable to CoCrMo/CoCrMo couple (1.2 mA/cm2 and 0.3, respectively). Information on the mechanical energy dissipated at the interface, the sticking behavior, and the load dependence of the inter-asperity distance calculated using the model elucidated the influence of mechanical factors on the experimental results. It was observed that the lowest amount of work was required to generate some of the highest fretting corrosion currents in Ti6Al4V/Ti6Al4V couples compared to the other combinations. The elements of the model presented here provide an excellent basis to explain many of the observed behaviors of these interfaces.
Analysis of Multichannel Signals using a Channel Simulator

Measurements of ion channel activities that generate multichannel events are important to understand, but difficult to analyze. In many cases the multichannel events are discarded instead of used in the analysis. The availability of a channel signal simulator offers an excellent opportunity to develop and test statistical models for analysis of multichannel signals. We have generated single channel traces for various open probabilities and then digitally superimposed these signals to obtain multichannel events. We then applied our analysis to these multichannel traces to calculate single channel parameters such as the average ON and OFF times and their second moments. In addition to allowing testing of statistical calculations, simulated channel data has pedagogical value when used as tutorials in statistical analysis, especially with regard to binomial distributions.
A miniature biofuel cell operating in a physiological buffer.

A glucose−O2 biofuel cell, consisting only of two electrocatalyst coated 7-μm diameter, 2-cm long carbon fibers is reported. The cell operated continuously at 0.52 V at 37 °C in a physiological buffer solution for a week, producing 1.9 μW during the first and 1.0 μW during the last day, generating in the period 0.9 J of electrical energy while passing a charge of 1.7 C. If a similar dimension zinc fiber were utilized in a battery at 100% current efficiency, only 0.016 C would have been generated.
Blood pressure determinants in living–related renal allograft donors and their recipients

Blood pressure determinants in living–related renal allograft donors and recipients. We studied 99 living related allograft donors with follow–up information of at least 10 years and the 50 recipients who had successful outcomes. Recipients were younger and had significantly lower blood pressures at follow–up than their donors. Borderline and definite hypertension were present in 22.2% and 4.0% of donors prior to donation, in 14.4% and 21.1% of donors at follow–up, and in 2.0% and 18.0% of the 50 recipients at follow–up. Age, relative weight, and mean arterial pressure (MAP) prior to donation were the key variables in predicting the follow–up ranked MAP of the donors. C PAH prior to donation was inversely correlated with the age of the donors and, indirectly, with the follow–up MAP. Donor C PAH prior to donation was significantly correlated with the renal allograft function of the recipients but not with the recipient ranked MAP at follow–up. No correlation of the ranked MAP or blood pressure outcome categories between donors and recipients was found. We conclude that donation of one kidney can accelerate the development of hypertension in those donors with predisposition to develop hypertension. In addition, the predisposition of the donors to develop hypertension and their age, within the range observed in the study, does not significantly influence the long–term blood pressure status of the recipient.
Sensitive, low damage surface analysis using resonance ionization of sputtered atoms

It is clear that in order to understand better the detailed mechanisms associated with sputtering it is necessary to develop new measurement techniques which can measure properties of neutral sputtered atoms with primary ion doses which are so low as to be essentially nondamaging. The results of a new surface analysis by resonance ionization of sputtered atoms (SARISA III) are reported here. Fe impurities in Si are measured at sub-ppb levels with removal of less than a surface monolayer.
Full correlation matrix analysis of fMRI data on Intel® Xeon Phi™ coprocessors

Full correlation matrix analysis (FCMA) is an unbiased approach for exhaustively studying interactions among brain regions in functional magnetic resonance imaging (fMRI) data from human participants. In order to answer neuroscientific questions efficiently, we are developing a closed-loop analysis system with FCMA on a cluster of nodes with Intel® Xeon Phi™ coprocessors. Here we propose several ideas for data-driven algorithmic modification to improve the performance on the coprocessor. Our experiments with real datasets show that the optimized single-node code runs 5x-16x faster than the baseline implementation using the well-known Intel® MKL and LibSVM libraries, and that the cluster implementation achieves near linear speedup on 5760 cores.
Fragmentation of calcium-based sorbents under high heating rate, short residence time conditions

A laser heating technique was developed to study the fragmentation behaviour of calcium-based sorbents under high heating rate, short residence time conditions. Eight geologically dissimilar, commercially available calcium-based sorbents were tested in the reactor using particle sizes in the range 37–105 μm. The fragmentation behaviour was a function of sorbent type, particle size and particle temperature over the range of 600–1600°C, with the sorbent type being the dominant parameter. Dolostones were more susceptible to breakage than limestones. The mechanism proposed for the fragmentation of the dolostones involves the rapid decomposition of the magnesium carbonate, which builds within the particles a sufficiently high pressure of CO2 to overcome the inherent mechanical strength.
An X-ray reflectivity study of β-NiAl oxidation

Abstract Early stages in the cyclic oxidation of β-NiAl at 500 °C were investigated using the technique of X-ray reflectivity. By fitting the reflectivity curves to a model function, oxide layer thickness, roughness of the oxide-gas and the oxide-substrate interfaces were obtained as a function of oxidation time. It was observed that the oxide thickness increased logarithmically with time. Comparison of the roughness of the oxide-substrate interface with that of the oxide-gas interface showed that the oxide-gas interface was rougher than the oxide-substrate interface. This is consistent with the postulated growth mechanism (outward diffusion of cations) for oxide growth during the early stages of oxidation at low temperatures in this material. Thus, X-ray reflectivity offers a convenient way of determining oxide growth rates along with the roughness of the interfaces when the oxide layer is thin; this regime cannot be easily studied with techniques that are currently being used for oxidation studies. Published by Elsevier Science Ltd.
Restriction enzymes and their isoschizomers

Since the last compilation of restriction enzymes (1), 300 new entries have been added including 12 new specificities. With the growing size of this database and the recognition that the most widespread use of the information is as a database for computer programs predicting restriction enzyme cleavage patterns, the new format has been continued. This format is intended to contain the minimal amount of information required by a computer program. It should be noted that only enzymes for which the recognition sequence is known are included. This new list is shown"in the first Table, while an alphabetical listing of all Type II enzymes is presented in the second Table. A copy of the restriction enzyme data base in its previous format (2), including enzymes of unknown recognition sequence, will be available upon request. It should also be noted that an alternative compilation of these enzymes has recently been produced (3).
Tailoring the Structure of Polymer Brushes Through Copolymer Architecture

Polymers tethered by one end onto a solid surface are referred to as polymer “brushes”. We consider brushes composed of copolymers that contain both A and B monomers. The A monomers are compatible with the surrounding solvent, while the B sites are solventincompatible. The solvent incompatibility causes the B sites to associate into domains or clusters within the layer. We use Monte Carlo computer simulations and self-consistent field calculations to determine the effect of copolymer architecture on the structure of the polymer brush. In particular, we alter the copolymer sequence distribution (the arrangement of the A and B monomers along the length of the chain) and determine how both the vertical and lateral morphology of the brush are effected by these variations. The results provide guidelines for controlling the size and shape of the B domains, and consequently, the morphology of the tethered layer.
Investigating the relationships among rising fuel prices, increased transit ridership, and CO2 emissions

The increase in US transit ridership in 2008 has been attributed to the increase in fuel price. This study investigates the extent to which the increase in fuel price influenced the use of transit and whether this in turn influenced the reduction in CO2 emissions. The results indicate that the number of transit trips in an urban area increases significantly with increase in fuel price. Change in fuel cost also has a negative association with emissions although changes in transit trips do not have significant association with CO2 emissions.
Coal burning properties determined from CO2 profiles

Abstract We are investigating a method for simultaneous determination of devolatilization and char burnout times based on the analysis of CO 2 emissions from a fluidized bed combustor. The technique is nonintrusive and can be performed under realistic combustion conditions. Our method involves batching coal samples in a fluidized bed combustor that is heated with propane gas or other fuel. To validate our technique, control tests were carried out using single-sized coal. Carbon dioxide profiles versus time for the batch tests are analyzed with linear models to obtain characteristic time constants for coal devolatilization and char combustion. The technique gives results that are comparable to times measured by more conventional, visual techniques. Our approach does not require special sample preparation, can be performed in actual combustion equipment, and employs standard boiler instrumentation.
Swelling characteristics of gel fractions of formaldehyde‐modified cotton celluloses

A method for assessing extent of swelling of the gel fraction of formaldehyde-modified cottons, employing cupriethylenediamine hydroxide as the swelling agent, is described. Substantial differences in apparent specific volumes of swollen gel fractions are observed for cottons crosslinked by different processes to the same level of agent. The apparent crosslink density measured by the swelling of gel fraction increases with formaldehyde content of the cotton; at 0.20% formaldehyde the order of increasing crosslink density in the various processes of reaction is as follows: nonaqueous system (forms D and D′) < aqueous system (forms W and W′) <swelling system (form F) < vapor system (form V) < bake-cure system (form C).
Racial profiling and the ‘French exception’:

‘The “exceptional” nature of the French cultural and political tradition’, as scholar Catherine Raissiguier sees it ‘resides … in its ability to foreground a strong discourse of universal inclusion and equality along with its unique resistance to acknowledging exclusionary and discriminatory discourses and practices both in its past and in its present’ (2010: 1). In keeping with Raissiguier’s conceptualisation, les controles au facies (which translates as ‘racial profiling’) fit squarely within this model at this moment when politicised discourse racialises diversity and defines it as a threat to personal and national security. The French Republican model functions in this context as an authoritarian mode of assimilation and universalism that seeks to destroy difference at the expense of equality and inclusion. These ‘controls’ are only, however, the surface of a deeper and more insidious problem in French society that continues to go misnamed and thus mishandled: race.
Time-Stratigraphic Reconstruction and Integration of Paleopedologic, Sedimentologic, and Biotic Events (Willwood Formation, Lower Eocene, Northwest Wyoming, U.S.A.)

Relative paleosol maturities are inversely proportional to the accumulation rates of the sediment upon which they formed, and are therefore excellent relative indicators of how much geologic time elapsed between any two horizons. An empirically-based model is advanced using paleosol maturities to estimate the relative geologic time separating any stratigraphic levels within the lower Eocene Willwood Formation. The revised Willwood time stratigraphy from this analysis helps evaluate the nature, tempo, and possible causes of three major episodes of mammalian appearance and disappearance. These faunal events are directly correlated with certain aspects of paleosol evolution in the Willwood Formation. That evolution is tied directly to climatic changes and to varying sediment accumulation rates in response to tectonism. The first faunal turnover occurs at the base of the Willwood Formation. It coincides with a major increase in pedogenic maturity, reflecting a major decrease in sediment accumulation rate, and accompanying general climatic warming at about the time of the Paleocene-Eocene boundary. Throughout the remainder of Willwood time, there was a gradual, yet continual, decrease in paleosol maturity and degree of hydromorphy, probably related to the progressive structural elevation of the Owl Creek antiform bounding the south and southeast margins of the Bighorn Basin.more » This gradual decrease was punctuated by two intervals of more significant decline in paleosol maturity and in the incidence of hydromorphic soils. Both intervals are also marked by faunal turnovers. These sedimentologic and biologic events may reflect tectonic, periods when the rate of basin subsidence increased more rapidly. 58 refs., 7 figs., 2 tabs.« less
Remembrance of Antigens Past: New Insights into Memory T Cells

Memory immune responses against foreign antigens protect the host from pathogens previously encountered via illness or vaccination, yet can also contribute to the pathology of autoimmune disease when generated against self-antigens. Memory immune responses are classically attributed to the reactivation of long-lived, antigen-specific T lymphocytes that arise directly from differentiated effector T cells and persist in a uniformly quiescent state. Recent findings in both humans and mice, using new biochemical, molecular and cellular approaches, have identified novel features of memory T cells providing new insight into models for memory cell development and differentiation. Biochemical and molecular studies on memory T cells have identified novel markers for memory T cells that may play integral roles in their generation and maintenance. Recent cellular immunological studies have uncovered remarkable heterogeneity amongst antigen-specific memory T cells. Memory cell heterogeneity in the expression of homing and chemokine receptor delineates functional subsets of memory T cells that differ in their proliferative capacity, differentiation potential, homing properties and protective abilities. These findings suggest that memory T cells with diverse properties residing in both lymphoid and nonlymphoid tissues may be necessary to elicit a rapid and effective protective recall immune response involving both cellular and humoral immunity.
Improving the throughput of point-to-multipoint ARQ protocols through destination set splitting

An approach to improving the performance of point-to-multipoint automatic repeat request (ARQ) protocols is considered. The approach involves splitting the destination set into disjoint groups and having the source carry out independent time multiplexed conversations with each group. The performance of memoryless and limited-memory versions of stop-and-wait and go-back-N protocols was investigated and the question of how to pick an optimal grouping of nodes was addressed. The results indicate that destination set splitting can improve the throughput of point-to-multipoint ARQ protocols, particularly if the receivers' capabilities are not identical. >
Use of smoothed pseudo Wigner distribution in classifying hormonal time series

The discrete smoothed pseudo Wigner distribution is used to process the cortisol time series of both pituitary and ectopic origins for possible visual discrimination in the time-frequency domain. This technique considers the smoothed pseudo Wigner distribution as an image representation. It compares the results of the smoothed pseudo-Wigner distribution after two different filtering processes: one uses a simple averaging filter, and the other uses a preprocessing filter. If their ratio is greater than a selected threshold and the original smoothed pseudo Wigner distribution is positive, then the latter is considered as an autocomponent. Otherwise, it is considered as a cross component and is set to zero. >
Type IV Pilus-Dependent Motility and Its Possible Role in Bacterial Pathogenesis

Type IV pili (TFP) are very unique appendages on the bacterial surface. They are not only required for microbial adherence but also involved in bacterial movement, such as social gliding motility in Myxococcus xanthus and twitching motility in Pseudomonas and Neisseria species ([33][1]). How
The Alignment of Global Management Strategies, International Communication Approaches, and Individual Rhetorical Choices

The international strategies of an organization—ethnocentric, polycentric, geocentric, heterarchic—are reflected in its international communication. The discussion presented here, based on Hedlund's application of Perlmutter's categorization of management strategies, focuses on the alignment of an organization's goals and market positions with its international communication approaches. The categorization implies that an organization's global management strategies should be aligned with its international communication practices. As such, an organization that seeks a larger role in the international market yet takes an ethnocentric stance in its communication strategies may be less successful than one with a more polycentric, geocentric, or heterarchic approach to international communication. Thinking about international communication within such a framework enhances not only consulting practice but teaching as well.
Intraductal Papillary Mucinous Neoplasms of the Pancreas (IPMNs): New Insights on Clinical Outcomes and Malignant Progression

Intraductal papillary mucinous neoplasms (IPMNs) are cystic tumors of the pancreas that can progress into invasive carcinomas. Main duct IPMN is usually treated with surgery while branch duct IPMN is surgically resected if it is high risk based on certain features of the tumor (mostly radiographic) that do have some limitations. Predicting the risk of malignant progression has been lately the main focus of research especially that comprehending the molecular pathogenesis of the disease has emerged as a valuable means to better understand the disease and thus guide disease management. We will present two abstracts from the ASCO Annual Meeting. The first compares the clinical outcomes of pancreatic ductal carcinoma and IPMN associated cancer, and the second looks at the pathogenesis of the disease at the cellular and molecular levels to predict high risk disease. Image: Stained glass windows by Tommaso Juglaris at Goddard Chapel at Tufts University. Medford, MA, USA
Understanding people pointing: the Perseus system

We present Perseus, a purposive visual system used by our robot, CHIP, to locate objects being pointed at by people. Perseus uses knowledge about the task and environment at all levels of processing to more accurately and efficiently perform visual tasks.
Kismet/CHD7 regulates axon morphology, memory and locomotion in a Drosophila model of CHARGE syndrome

CHARGE syndrome (CS, OMIM #214800) is a rare, autosomal dominant disorder, two-thirds of which are caused by haplo-insufficiency in the Chd7 gene. Here, we show that the Drosophila homolog of Chd7, kismet, is required for proper axonal pruning, guidance and extension in the developing fly's central nervous system. In addition to defects in neuroanatomy, flies with reduced kismet expression show defects in memory and motor function, phenotypes consistent with symptoms observed in CS patients. We suggest that the analysis of this disease model can complement and expand upon the existing studies for this disease, allowing a better understanding of the role of kismet in neural developmental, and Chd7 in CS pathogenesis.
Multijunction Photovoltaic Technologies for High-Performance Concentrators

Multijunction solar cells provide high-performance technology pathways leading to potentially low-cost electricity generated from concentrated sunlight. The National Center for Photovoltaics at the National Renewable Energy Laboratory has funded different III-V multijunction solar cell technologies and various solar concentration approaches. Within this group of projects, III-V solar cell efficiencies of 41% are close at hand and will likely be reported in these conference proceedings. Companies with well-developed solar concentrator structures foresee installed system costs of $3/watt?half of today's costs?within the next 2 to 5 years as these high-efficiency photovoltaic technologies are incorporated into their concentrator photovoltaic systems. These technology improvements are timely as new large-scale multi-megawatt markets, appropriate for high performance PV concentrators, open around the world.
The nonlinear mixed effects model with a smooth random effects density

SUMMARY The fixed parameters of the nonlinear mixed effects model and the density of the random effects are estimated jointly by maximum likelihood. The density of the random effects is assumed to be smooth but is otherwise unrestricted. The method uses a series expansion that follows from the smoothness assumption to represent the density and quadrature to compute the likelihood. Standard algorithms are used for optimization. Empirical Bayes estimates of random coefficients are obtained by computing posterior modes. The method is applied to data from pharmacokinetics, and properties of the method are investigated by application to simulated data.
Lifetime of the long-lived isomer of 236Np from α-, β- and electron-capture decay measurements

Abstract The half-life of long-lived 236Np, due to α, β and electron-capture decay, was found to be 1.55 × 105 yr. Of all decays, 88% populate excited states in 236U and 12% populate levels in 236Pu. Lifetimes measured by growth of the ground states of 236U and 236Pu agree with values from corresponding γ de-excitations in these daughter nuclei. Therefore, nearly all the electron-capture decays populate the 6+ level of the ground-state band in 236U. Similarily, essentially all the β− decay populates an analogous 6+ level in 236Pu, which de-excites through a previously unreported transition of 158.3 keV. If a very weak γ-ray at 894 keV can be ascribed to a level in 232U populated by β decay of 232Pa, its existence establishes a 0.2% α-branching decay in 236Np.
Gender and race/ethnic differences in inaccurate weight perceptions among U.S. adolescents.

Purpose Inaccurate weight perceptions may lead to unhealthy weight control practices among normal weight adolescents and to a greater risk of adult obesity and related morbidities for overweight adolescents. To examine which U.S. adolescents are at risk of these outcomes, we examine gender and racial/ethnic differences in weight perception inaccuracy. This is the first study of weight perception inaccuracy to include Latino/a and Asian American adolescents. Methods Among the 12,789 Wave II participants of the National Longitudinal Study of Adolescent Health, we estimate multivariate models that reveal how gender, race/ethnicity, and clinical weight categories predict weight perception inaccuracy. Results Relative to boys, girls have lower odds of underestimating their weight and greater odds of overestimating their weight. In particular, among overweight and obese adolescents, girls are more accurate than boys, but among normal weight adolescents, boys are more accurate. Compared with Whites, African Americans are more likely to underestimate their weight, particularly among overweight girls and obese boys. Overall and particularly among girls and normal weight adolescents, African Americans are less likely to overestimate their weight than their White counterparts. Finally, Asian American girls are more likely to underestimate their weight than White girls. Conclusion These findings have important implications for identifying and intervening with adolescents at the greatest risk of long-term weight problems, weight-related morbidity, and unhealthy weight control practices.
A Measurement of the Adaptation of Color Vision to the Spectral Environment

An exploratory factor analysis of the reflectance spectral distributions of a sample of natural and man-made objects yields a factor pattern remarkably similar to psychophysical color-matching curves. The goodness-of-fit indices from a maximum likelihood confirmatory factor model with fixed factor loadings specified by empirical trichromatic color-matching data indicate that the human visual system performs near to an optimum value for an ideal trichromatic system composed of three linear components. An unconstrained four-factor maximum likelihood model fits significantly better than a three-factor unconstrained model, suggesting that a color metric is better represented in four dimensions than in a three-dimensional space. This fourth factor can be calculated as a nonlinear interaction term between the first three factors: thus, a trichromatic input is sufficient to compute a color space of four dimensions. The visual system may exploit this nonlinear dependency in the spectral environment in order to ob...
Irs2 and Irs4 synergize in non-LepRb neurons to control energy balance and glucose homeostasis.

Insulin receptor substrates (Irs1, 2, 3 and Irs4) mediate the actions of insulin/IGF1 signaling. They have similar structure, but distinctly regulate development, growth, and metabolic homeostasis. Irs2 contributes to central metabolic sensing, partially by acting in leptin receptor (LepRb)-expressing neurons. Although Irs4 is largely restricted to the hypothalamus, its contribution to metabolic regulation is unclear because Irs4-null mice barely distinguishable from controls. We postulated that Irs2 and Irs4 synergize and complement each other in the brain. To examine this possibility, we investigated the metabolism of whole body Irs4−/y mice that lacked Irs2 in the CNS (bIrs2−/−·Irs4−/y) or only in LepRb-neurons (Lepr∆Irs2·Irs4−/y). bIrs2−/−·Irs4−/y mice developed severe obesity and decreased energy expenditure, along with hyperglycemia and insulin resistance. Unexpectedly, the body weight and fed blood glucose levels of Lepr∆Irs2·Irs4−/y mice were not different from Lepr∆Irs2 mice, suggesting that the functions of Irs2 and Irs4 converge upon neurons that are distinct from those expressing LepRb.
Where angels fear to tread: proxy consent and novel technologies.

Background: Individuals suffering from severe disorders of consciousness (DOC) face a bleak prognosis and are susceptible to therapeutic neglect according to Fins. Because of the increasing occurrence of severe brain injury, some physicians and researchers take the study of DOC to be a moral imperative and perceive novel technologies, such as Deep Brain Stimulation (DBS), as offering potential therapeutic benefit.Method: This article examines the decisional process faced by proxy decision-makers for patients with severe DOC when confronted by novel treatments such as DBS.Results: If there is awareness in the literature that surrogate consent is complicated by the contingencies of severe brain injury such as disability and the possibility of long-term care, surrogate consent is often equated with substituted judgement and taking the best interests of the patient into account. However, for surrogates of patients with severe DOC, advocacy becomes a central component of the surrogate's role as there is no est...