cssi/SciSciGPT-SciSciNet huggingface dataset:
Signal-to-noise ratio of the intensity-dependent spread filter and its reconstruction

In this paper equations for the output mean and variance of the intensity-dependent spread (IDS) filter and its reconstruction are derived for images corrupted by white Gaussian and white Poisson noise. These equations are then used to compute the signal-to-noise ratio (SNR) in both the filtered image and the reconstructed image. We show that for additive Gaussian noise the SNR in the reconstructed image varies as the square root of the mean intensity and for additive Poisson noise the SNR is constant. We compare the SNR in the reconstructed image with that of the linear-shift-invariant Gaussian filter, and we show that the IDS filter can achieve a specified minimum SNR over the image with substantially less blur than a Gaussian. We also derive a formula to trade off blur for SNR by adjusting the spread factor of the IDS kernel.
In vitro activity of sparfloxacin (AT-4140 and CI-978), a new quinolone antimicrobial agent, against Haemophilus and gram-positive cocci.

Abstract Sparfloxacin (AT-4140 and CI-978) was evaluated for activity against 194 clinical isolates of staphylococci, streptococci, Enterococcus faecalis , anaerobic Gram-positive cocci, and Haemophilus sp. The MIC of sparfloxacin for >93% of the strains tested was ⩽0.5 μ g/ml. Sparfloxacin demonstrated increased activity against enterococci, staphylococci, pneumococci, and anaerobic cocci when compared with ciprofloxacin.
Application of radioactive sources in analytical instruments for planetary exploration.

Radioactive isotopes have been used in analytical instrumentation for planetary exploration since the very beginning of the space age. An Alpha Scattering Instrument (ASI) on board the Surveyor 5, 6 and 7 spacecrafts used the isotope (242)Cm to obtain the chemical composition of the lunar surface material in 1960s. The Alpha Proton X-ray Spectrometers (APXS) used on several mission to Mars (Pathfinder, Mars-96, Mars Exploration Rovers (MER) and on the Mars Science Laboratory (MSL), the next mission to Mars in 2011 and on the Rosetta mission to a comet) are improved derivatives of the original ASI, complimented with an X-ray mode and using the longer lived (244)Cm isotope. (57)Co, (55)Fe and many other radioisotopes have been used in several missions carrying XRF and Mossbauer instruments. In addition, (238)Pu isotope is exclusively being used in most of the space missions for heating and power generation.
Using retrospective sampling to estimate models of relationship status in large longitudinal social networks

Estimation of longitudinal models of relationship status between all pairs of individuals (dyads) in social networks is challenging due to the complex inter-dependencies among observations and lengthy computation times. To reduce the computational burden of model estimation, a method is developed that subsamples the "always-null" dyads in which no relationships develop throughout the period of observation. The informative sampling process is accounted for by weighting the likelihood contributions of the observations by the inverses of the sampling probabilities. This weighted-likelihood estimation method is implemented using Bayesian computation and evaluated in terms of its bias, efficiency, and speed of computation under various settings. Comparisons are also made to a full information likelihood-based procedure that is only feasible to compute when limited follow-up observations are available. Calculations are performed on two real social networks of very different sizes. The easily computed weighted-likelihood procedure closely approximates the corresponding estimates for the full network, even when using low sub-sampling fractions. The fast computation times make the weighted-likelihood approach practical and able to be applied to networks of any size. Estimation of statistical models for social networks is challenging.Dyads with no relationship ("null-dyads") are common in large social networks.Propose to subsample the "always-null" dyads.Develop weighted likelihood Bayesian estimation method.Method enables large social networks to be analyzed feasibly and accurately.
First Evaluation of the WASP, a New Automated Microbiology Plating Instrument

Many laboratories are experiencing growing shortages of trained microbiology technologists and technicians. Consequently, there is considerable interest in new automation that could potentially lessen labor demands for specimen processing. In this study, we present the first published evaluation of a new microbiology instrument, the Walk Away Specimen Processor (WASP), manufactured by Copan, Inc., in which we evaluated cross-contamination, the accuracy of plating, and the quality of the results. The absence of cross-contamination was demonstrated by plating a total of 200 alternating inoculated and sterile specimen tubes. The ability of the WASP to subculture enrichment broths was evaluated with 106 Lim broth specimens, with the results being identical to those obtained by testing by routine methods. Plating of urine specimens with the WASP was compared to plating with the Dynacon Inoculab instrument. Three hundred specimens were plated in duplicate on both instruments with 1-μl loops, and 293 specimens were plated in duplicate on both instruments with 10-μl loops. The results of duplicate plating with the same instrument (replicate plating) and of the consensus agreement between the two instruments were compared. The replicate plating results were comparable for both instruments, while the WASP had more specimens with significant results than the Inoculab with the 1-μl loop only. Lastly, for the plating of 113 specimens in ESwab tubes, the manual method and WASP plating each yielded 90 potential pathogens. In summary, we report the first evaluation of a new microbiology specimen-plating instrument, the WASP, which offers opportunities for the automated plating of microbiology specimens to an extent that has not been possible to date.
Polyethers. XII. Poly‐(2,6‐disubstituted‐1,4‐phenylene oxides)

A number of poly(p-phenylene oxide) polymers have been prepared from 4-bromophenols with various combinations of methyl, propyl, allyl, and phenyl groups in the 2,6-positions. Potassium ferricyanide, lead dioxide, and 2,4,6-tri-tert-butylphenoxy radical have been used as initiators. The reactions proceed to higher molecular weights under nitrogen. These polymers are soluble resins of low molecular weight, softening somewhat above 100°. Those with allyl groups become insoluble and infusible on exposure to air for several days.
Management of location-based services innovation: Insights from consumers

In this project, we examine the effects of three individual-level factors - consumption values, privacy concerns, and subjective norms - on consumers' intention to adopt location-based services (LBS) on their mobile phones. A research model was created based on the Theory of Consumption Values, and tested by survey data from potential adopters. Structural equation modeling was conducted using SmartPLS. We found that consumption values positively whereas privacy concerns negatively influenced intention to adopt LBS; subjective norms were found not to impact intention. In addition, consumer intention to spread positive word-of-mouth about LBS was studied as another outcome measure. Both consumption values and subjective norms positively affected the measure, whereas privacy concerns did not. Managerial implications and theoretical contributions of the project are discussed.
Exploration of the Polar Upper Atmosphere

Exploration of the Polar Upper Atmosphere is primarily a compilation of tutorial lectures on the many aspects of geophysics that comprise research of the high latitude atmosphere and its extension into space. The topics covered range from the stratosphere to the solar wind, touching on neutral and plasma dynamics as well as atmospheric chemistry. On reading this volume one will probably be impressed with the breadth of the field and with the breadth of knowledge that is required for understanding. This impression is undoubtedly enhanced by the fact that the NATO Advanced Study at which these lectures were given was broader in scope than were previous advanced studies on similar topics.
Electroacoustic Performance of Direct-Input Hearing Aids with FM Amplification Systems

The purpose of this paper was to provide audiologists practical information regarding the use of direct-input hearing aids with FM systems. The degree to which the electroacoustic characteristics of direct-input hearing aids were preserved when used with two different personal FM systems was evaluated. Although there were limited changes in saturation sound pressure level and harmonic distortion, there was an increase in equivalent-input noise and full-on-gain. The frequency response curve of the aid + FM condition relative to the aid alone differed in the high frequencies for the two FM systems. Aids with equivalent gain values had varying amounts of gain when tested with the FM systems set at a constant volume control setting. This variability in the electroacoustic response of a given aid when coupled to a personal FM system suggests that one may not assume characteristics of the hearing aid are maintained when it is used with an FM system.
Right brain: humor completes the neurologic examination.

Most of us tend to remember moments that define the major decisions in our lives, the events that make indelible impressions in our minds. In the monotony of our daily existence, remembering these moments helps give us perspective. It helps remind us why we do what we do. When I think back on the pivotal moments that pushed me to become a neurologist, I always remember a face—a smiling face of a young girl.
Elimination versus displacement reactions: an alternative mechanistic interpretation of The anomalous reactions of F-propene dimers with thiolate ions

Abstract In 1979 Ishikawa and Maruta reported experimental studies of the reaction of two F -propene dimers, the F -2- and 4-methyl-2-pentenes with thiolate ions. Highly unexpected products, the mercapto derivatives of F -4-methyl-1,3-pentadiene, were isolated. These authors proposed a novel mechanism which included the unprecedented 1,4-elimination of a sulfenyl fluoride from a fluorinated thioether. In the current paper the energetics of this reaction are explicitly discussed and an alternative, more precedented, mechanism is offerred.
Effect of NDGA, a lipoxygenase inhibitor, on prolactin actions in mouse mammary gland explants.

Abstract Nordihydroguaiaretic acid (NDGA) at a concentration of 50 μM abolished the actions of prolactin on RNA, casein and lipid biosynthesis in cultured mouse mammary gland explants. NDGA at 100 μM also reduced the magnitude of the prolactin stimulation of ornithine decarboxylase activity. Since NDGA is known to be an inhibitor of lipoxygenase activity, we would conclude that ongoing leukotriene synthesis may be essential for prolactin to express at least certain of its lactogenic actions in the mammary gland.
Three-dimensional local structure of photoexcited Cu diimine complex refined by quantitative XANES analysis.

The structural details of [Cu(dmp){sub 2}]{sup +} (dmp = 2,9-dimethyl-1,10-phenanthroline) at its metal-to-ligand charge-transfer (MLCT) excited-state in acetonitrile were extracted using quantitative analysis of Cu K-edge X-ray adsorption near edge structure (XANES). The study combines two techniques: fitting experimental XANES spectra with a multidimensional interpolation approximation, and calculating theoretical XANES spectra with molecular potentials beyond the muffin-tin approximation. The results of the study show that the best fit of the experimental XANES data must include a solvent molecule binding to the Cu with a short Cu-N distance of 2.00 {angstrom}. This confirms that the formation of an exciplex is responsible for the excited-state quenching in coordinating solvents, such as acetonitrile. Moreover, the calculations suggest that the formation of this exciplex state is accompanied by significant rocking distortions of the dmp ligands resulting in a 108{sup o} angle between the N(solvent)-Cu bond and the C{sub 2} symmetry axis of the dmp ligand. This combined approach allows us to extract molecular configurations that would otherwise be missed in a conventional qualitative XANES analysis.
Defect tolerant probabilistic design paradigm for nanotechnologies

Recent successes in the development and self-assembly of nanoelectronic devices suggest that the ability to manufacture dense nanofabrics is on the near horizon. However, the tremendous increase in device density of nanoelectronics will be accompanied by a substantial increase in hard and soft faults, posing a major challenge to current design methodologies and tools. In this paper we propose a novel probabilistic design paradigm for defective but reconfigurable nanofabrics. The new design goal is to devise an appropriate structural/behavioral decomposition which improves scalability by constraining the reconfiguration process, while meeting a desired probability of successful instantiation, i.e, yield. Our approach not only addresses the scalability problem in configuring dense nanofabrics subject to defects, but gives a rich framework in which critical trade-offs among performance, yield, and per chip cost can be explored. We present a concrete instance of the approach and show extensive experimental results supporting these claims.
Fabrication of Highly Ordered TiO2 Nanotube Arrays Using an Organic Electrolyte

Anodization of titanium in a fluorinated dimethyl sulfoxide (DMSO) and ethanol mixture electrolyte is investigated. The prepared anodic film has a highly ordered nanotube-array surface architecture. Using a 20 V anodization potential (vs Pt) nanotube arrays having an inner diameter of 60 nm and 40 nm wall thickness are formed. The overall length of the nanotube arrays is controlled by the duration of the anodization, with nanotubes appearing only after approximately 48 h; a 72 h anodization results in a nanotube array approximately 2.3 μm in length. The photoelectrochemical response of the nanotube-array photoelectrodes is studied using a 1 M KOH solution under both UV and visible (AM 1.5) illumination. Enhanced photocurrent density is observed for samples obtained in the organic electrolyte, with an UV photoconversion efficiency of 10.7%.
Children's gender-role stereotypes: A sociological investigation of psychological models

This study investigates sociologically the predictions of the cognitive developmental, the social learning, and the interactive models of gender-role development. We examine the effect of a variety of variables on gender-role stereotyping among a sample of 1264 four-, five-, and six-year-old children enrolled in preschool programs in a major metropolitan area. Age, sex, and race are found to be significantly related to children's gender stereotypes. With age, children increasingly associate stereotypical behavior patterns with the male and female gender roles. Children are also found to demonstrate a higher degree of gender-role stereotyping with regard to members of their own sex. An age/sex interaction effect indicates that the tendency of children to demonstrate a higher degree of same-sex stereotyping is most pronounced among four-year-olds. Finally, black children are found to be less gender-typed in their images of males and females than are white children. These data suggest that the interactive model, including both social and cognitive factors, is the best explanation of these data and should be further investigated.
Analytical Queueing Models

Increased use of analytical performance models can be attributed, in part, to a very simple fact: they work.
Compact model of slug flow in microchannels

This paper presents a theoretical investigation of the movement of liquid droplets and slugs in hydrophobic microchannels and develops a compact model for this type of two-phase flow. This model is used in the prediction of pressure drop and liquid water coverage ratio, key parameters in the operation of Proton Exchange Membrane Fuel Cells (PEMFC), the primary motivation for this work. A semiempirical, periodic-steady two-phase separated flow compact model is formulated to characterize the slug flow behavior. The momentum equation includes the effects of acceleration, friction and surface tension on the pressure drop. The model considers spatial changes in slug velocity through the use of a force balance formulation. The model uses a departure scheme that computes slug size and shape at entrainment. The steady state slug flow compact model is capable of predicting liquid water coverage ratio and pressure drop using liquid and gas flow rates and advancing/receding triple point contact angles as its only inputs. The results indicate that the pressure drop increases as the droplet formation frequency increases.
Trypanosoma brucei: New radioisotope assay for quantitating cell lysis

Abstract A new radioisotope technique for quantitatively determining the extent of cell lysis of trypanosomes is described. Trypanosoma brucei was pulse-labeled with [3H]leucine and then incubated at 37 C in lytic (human serum) or nonlytic (rabbit serum) media. The release into the incubation medium of radioactively labeled intracellular macromolecules was then determined. A linear relationship was found between the release of TCA-precipitable radioactivity and lysis, as determined by conventional hemacytometer counting. This method is used to quantitate the trypanocidal activity in normal human serum.
The de Haas-van Alphen effect and Fermi surface of the ordered alloy β′-AgZn

The de Haas-van Alphen effect has been measured in the ordered alloy β′-AgZn by the modulation method, improving and extending the results of earlier observations. The results are in good agreement with recent theoretical calculations of the Fermi surface, although some of the predicted orbits have not been observed. The hole octahedron in the first band and the triangular hole in the second band have been identified unambiguously, and the shape of the octahedron has been determined by inversion.
Protective specific immunity induced by cyclophosphamide plus tumor necrosis factor α combination treatment of EL4-lymphoma-bearing C57BL/6 mice

A combination treatment protocol initiated 12 days after tumor injection, when the tumor was large, by administering cyclophosphamide (CY, 150 or 250 mg/kg) intraperitoneally followed by intravenous tumor necrosis factor α (TNFα, 1000 units/injection) on days 13, 16, 18, 21, and 23, resulted in about 60% longterm survival (i.e., survival for at least 60 days) in the syngeneic C57BL/6 mouse/EL4 lymphoma model system. The establishment of a specific antitumor immune memory and its possible therapeutic relevance was verified by reinjecting 60-day survivors with EL4 cells; all 60-day survivors that had received the combination treatments rejected the implants and survived for a further 60 days. Thymic cellularity was reduced during treatment and its recovery appeared to correlate with long-term survival and immunity. Thymocytes from mice treated with the combination were found to express significant levels of specific anti-EL4 cytolytic activity following a 4-day stimulation culture with X-irradiated EL4 cells and low concentrations of interleukin-2. This response could not be generated with thymocytes from naive animals. In each case the effect seen with the combination of a moderate CY dose (150 mg/kg) with TNFα was better than that seen with either dose of CY alone and equal to or better than that seen with the higher dose of CY combined with TNFα. These results indicate that treatment with a single moderate dose of CY in combination with TNFα is effective against a large, established tumor in this murine model. Furthermore, all the long-term survivors induced by this treatment developed protective immunity against reimplanted tumor and demonstrated a long-term specific immune memory in the thymus.
Synthesis, characterization, and computational studies of 6-(RR'N)-nido-5,7-C2B8H11: a polyborane cluster with a cage-boron having an exopolyhedral dative boron-nitrogen double bond.

The reactions of the arachno-4,6-C2B7H13 carborane with the secondary and primary amines, Me2NHBH3 and tBuNH2BH3, in ionic liquid media result in both boron-insertion into the cage at a position across the two cage-carbons and additional hydrogen-elimination via the reaction of a hydridic B−H with a protonic amine N−H hydrogen to produce the 6-(RR′N)-nido-5,7-C2B8H11 carboranes. Computational characterizations of these compounds and the previously reported 6-ClC6H4-9-(RR′N)-nido-6-NB9H10 azaboranes indicate that the amine-nitrogens form unique exopolyhedral dative B═N double bonds with a cage-boron.
Neighborhood monitoring in ad hoc networks

Much research in ad hoc networks utilizes monitoring mechanisms to detect maliciously acting nodes. The faults that a system is exposed to range from simple omissions to packet manipulations and misrouting. Several monitoring techniques have been presented that address malicious behavior in specific environments, but each has their restrictive assumptions about detection and mitigation in hostile environments. We generalize the notion of malicious behavior of related research and outline a k-hop monitoring approach that allows us to drop many assumptions limiting previous work. Specifically, we include collaboration of malicious nodes, the presence of malicious nodes during neighborhood exploration, and misrouting. However, the approach exposes also the associated overhead in providing detection and correction thresholds.
A performance evaluation of scientific I/O workloads on Flash-based SSDs

Flash-based solid state disks (SSDs) are an alternative form of storage device that promises to deliver higher performance than the traditional mechanically rotating hard drives. While SSDs have seen utilization in embedded, consumer, and server computer systems, there has been little understanding of its performance effects with scientific I/O workloads. This paper provides a trace driven performance evaluation of scientific I/O workloads on SSDs. We find that SSDs only provide modest performance gains over mechanical hard drives due to the write-intensive nature of many scientific workloads. Other workloads (like read-mostly web servers) would likely see much larger gains. Additionally, we observe that the concurrent I/O (when multiple parallel processes simultaneously access a single storage device) may significantly affect the SSD performance. However, such effects appear to be dependent on specific SSD implementation features and they are hard to predict in a general fashion. These results suggest that abundant cautions are needed when supporting high-performance scientific I/O workloads on Flash-based SSDs.
Superlinearly Convergent Quasi-Newton Algorithms for Nonlinearly Constrained Optimization Problems

A class of algorithms for nonlinearly constrained optimization problems is proposed. The subproblems of the algorithms are linearly constrained quadratic minimization problems which contain an updated estimate of the Hessian of the Lagrangian. Under suitable conditions and updating schemes local convergence and a superlinear rate of convergence are established. The convergence proofs require among other things twice differentiable objective and constraint functions, while the calculations use only first derivative data. Rapid convergence has been obtained in a number of test problems by using a program based on the algorithms proposed here.
Near-infrared emitting lanthanide complexes of porphyrin and BODIPY dyes

Abstract Near-infrared (NIR, 700–1600 nm) emitting lanthanide complexes offer great advantages over the conventional visible light emitting materials for bioimaging and sensing due to the deep penetration of NIR light in the biological fluids and low bleaching effect to the substrates. However, the application has been hampered by their poor NIR emission efficiency and the requirement of short excitation wavelengths. The porphyrin and BODIPY dyes are excellent chromophores with great potential to address these issues due to their unique photophysical properties and structural functionalities. In this review, our recent investigation on synthesis, structural analysis and photophysical properties of their lanthanide complexes is summarized and some important findings are highlighted. We focused on the synthesis and structural characterization of Yb 3+ , Nd 3+ and Er 3+ complexes of porphyrin and BODIPY dyes and the impact of structural changes on the NIR emission efficiency. Sensitization mechanism in these complexes is also discussed.
Cross-talk between Paracrine-Acting Cytokine and Chemokine Pathways Promotes Malignancy in Benign Human Prostatic Epithelium

The present study explores the mechanisms by which human prostatic carcinoma-associated fibroblasts (CAF) induce tumorigenesis in initiated but nonmalignant human prostatic epithelial cells (BPH-1). CAF express elevated levels of both transforming growth factor-β1 (TGF-β1) and stromal cell–derived factor-1 (SDF-1/CXCL12). TGF-β inhibits the growth of BPH-1 cells in vitro, but was found to be necessary for the tumorigenic response to CAF. This counterintuitive result suggested that the TGF-β signaling system was involved in other processes relating to tumorigenesis. The SDF-1 receptor, CXCR4, is expressed at low levels in benign prostate tissue and in BPH-1 cells in culture. However, CXCR4 levels increase during prostate cancer progression. CXCR4 was found to be induced and localized to the cell membrane in BPH1 cells by CAF-conditioned medium and by CAF cells in tissue recombinants. TGF-β was both necessary and sufficient to allow the detection of membrane-localized CXCR4 in BPH1 cells. Suppression of epithelial cell CXCR4 expression abrogated the tumorigenic response to CAF. SDF-1, secreted by CAF, acts via the TGF-β–regulated CXCR4 to activate Akt in the epithelial cells. This mechanism elicits tumorigenesis and obviates the growth-inhibitory effects of TGF-β. Thus, tumor stroma can contribute to carcinogenesis through synergism between TGF-β, SDF-1, and CXCR4. These experiments suggest mechanisms by which TGF-β can shift its role from an inhibitor to a promoter of proliferation during tumor progression. Both the TGF-β and SDF-1 pathways are targets of drug discovery efforts; these data suggest potential benefits in the cotargeting of these pathways. [Cancer Res 2007;67(9):4244–53]
Pneumonia in the Hospital Setting

1. Community Acquired Pneumonia and Sepsis (Beutz and Abraham) 2. The Systemic Response to Lung Infection (Deng and Standiford) 3. Pneumonia in the Solid Organ Transplant Patient (Chakinala and Trulock) 4. Non-Resolving Pneumonia (Weyers) 5. Antimicrobial Treatment of Hospital-Acquired Pneumonia (Fagon and Chastre) 6. Antimicrobial Treatment of Community-Acquired Pneumonia (Restrpo and Anzueto) 7. Prevention of Pneumonia in the Hospital Setting (Osmon and Kollef) 8. Antimicrobial Resistance and Treatment of Community Acquired Pneumonia (Mandell) 9. Etiology of Community-Acquired Pneumonia (Apisarthanarak and Mundy) 10. Mechanisms of Resistance of Bacteria Causing Ventilator-Associated Pneumonia (Szabo, Silveira, Fujitani and Paterson) 11. Etiology of Ventilator-Associated Pneumonia (Rello, Diaz and Rodriguez) 12. Preventing Pneumonia: The Role for Pneumococal and Influenza Vaccines (Shorr) 13. Genetic Susceptibility to Pneumonia (Waterer and Wunderink) 14. Microbiologic Diagnosis of Ventilator Associated Pneumonia (Baughman) 15. Pulmoary Host Defenses and Factors Predisposting to Lung Infection (Mason and Nelson) 16. Pathophysiology of Pneumonia (Alcon, Fabregas and Torres) 17. Acute Lung Injury and Bacterial Infection (Dreyfuss and Ricard)
A soluble, stable polyelectrolyte derivative of trypsin

Abstract A soluble ethylene maleic anhydride copolymer derivative of trypsin has been prepared. This derivative exhibits a shift in the pH optimum toward ca . 9–10 and it is stable in solution for extended periods of time. Digestion of oxidized ribonuclease indicates a change in specificity or reactivity versus native trypsin.
Broad-band frequency references in the near-infrared: Accurate dual comb spectroscopy of methane and acetylene

Abstract The Doppler-limited spectra of methane between 176 THz and 184 THz (5870–6130 cm−1) and acetylene between 193 THz and 199 THz (6430–6630 cm−1) are acquired via comb-tooth resolved dual comb spectroscopy with frequency accuracy traceable to atomic standards. A least squares analysis of the measured absorbance and phase line shapes provides line center frequencies with absolute accuracy of 0.2 MHz, or less than one thousandth of the room temperature Doppler width. This accuracy is verified through comparison with previous saturated absorption spectroscopy of 37 strong isolated lines of acetylene. For the methane spectrum, the center frequencies of 46 well-isolated strong lines are determined with similar high accuracy, along with the center frequencies for 1107 non-isolated lines at lower accuracy. The measured methane line-center frequencies have an uncertainty comparable to the few available laser heterodyne measurements in this region but span a much larger optical bandwidth, marking the first broad-band measurements of the methane 2ν3 region directly referenced to atomic frequency standards. This study demonstrates the promise of dual comb spectroscopy to obtain high resolution broadband spectra that are comparable to state-of-the-art Fourier-transform spectrometer measurements but with much improved frequency accuracy. Work of the US government, not subject to US copyright.
Control of the conjugation length and solubility in electroluminescent polymers

A new type of cyclolinear polymer, poly(phenylene vinylene-alt-cyclotriphosphazene), was synthesized through Heck-type coupling reactions to produce π-conjugated macromolecules with excellent solubility and precise electronic control of the band-gap energy. This synthesis method is capable of producing well-defined alternating polymers. The method is highly adaptable and can be readily used for other chromophore systems. The resulting polymers were also capable of accommodating a wide variety of substituents on the cyclophosphazene rings with minimal effect on the electronic properties. The band gap and electron affinities of the polymer were varied through the manipulation of the π-conjugated unit located between the insulating phosphazene rings. Each chromophore matched the intended conjugation length consistently throughout the macromolecules. The polymers were good film formers because of the chosen substituents on the phosphazene rings. The absorbance of the polymers indicated minimal spectral shift from the monomer absorbance. This suggested an effective insulation of each chromophore unit from its neighbors by the phosphazene rings. Solution photoluminescence efficiencies were found to be up to 44.1%. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 69–76, 2006
Anthropogenic carbon dioxide transport in the Southern Ocean driven by Ekman flow

Modelling studies suggest that more than 40% of the carbon dioxide produced from fossil fuels is taken up by the Southern Ocean, yet observations suggest that relatively little CO2 is retained there. Takamitsu Ito and colleagues use a high-resolution circulation and carbon cycle model to investigate the mechanisms controlling the fate of carbon in the Southern Ocean sink on a timescale of two years. They find that the primary mechanism for moving anthropogenic carbon dioxide is Ekman transport — a wind-driven surface current — but that there is also a complex interplay between Ekman flow, ocean eddies and the subduction of water masses. The analysis reveals intimate connections between carbon uptake by the ocean and climate variability through the variability of Ekman transport with time. The Southern Ocean is potentially a substantial sink of anthropogenic carbon dioxide; however, the regulation of this carbon sink by the wind-driven Ekman flow, mesoscale eddies and their interaction is under debate. Here, a high-resolution ocean circulation and carbon cycle model is used to study intra-annual variability in anthropogenic carbon dioxide over a two-year time period; the Ekman flow is found to be the primary mechanism of anthropogenic carbon dioxide transport across the Antarctic polar front. The Southern Ocean, with its large surface area and vigorous overturning circulation, is potentially a substantial sink of anthropogenic CO2 (refs 1–4). Despite its importance, the mechanism and pathways of anthropogenic CO2 uptake and transport are poorly understood. Regulation of the Southern Ocean carbon sink by the wind-driven Ekman flow, mesoscale eddies and their interaction is under debate5,6,7,8. Here we use a high-resolution ocean circulation and carbon cycle model to address the mechanisms controlling the Southern Ocean sink of anthropogenic CO2. The focus of our study is on the intra-annual variability in anthropogenic CO2 over a two-year time period. We show that the pattern of carbon uptake is correlated with the oceanic vertical exchange. Zonally integrated carbon uptake peaks at the Antarctic polar front. The carbon is then advected away from the uptake regions by the circulation of the Southern Ocean, which is controlled by the interplay among Ekman flow, ocean eddies and subduction of water masses. Although lateral carbon fluxes are locally dominated by the imprint of mesoscale eddies, the Ekman transport is the primary mechanism for the zonally integrated, cross-frontal transport of anthropogenic CO2. Intra-annual variability of the cross-frontal transport is dominated by the Ekman flow with little compensation from eddies. A budget analysis in the density coordinate highlights the importance of wind-driven transport across the polar front and subduction at the subtropical front. Our results suggest intimate connections between oceanic carbon uptake and climate variability through the temporal variability of Ekman transport.
Percutaneous Left Ventricular Assist Devices

Percutaneous left ventricular assist devices (P-LVADs) can be life saving and may permit the stabilization of a patient in cardiovascular collapse who would otherwise face imminent demise. For specific patients and clinical indications, or where a greater degree of hemodynamic support is required, numerous studies have demonstrated the feasibility and safety of the newer generation P-LVADs. The potential applications for P-LVADs have continued to expand, now including diverse uses such as support for cardiogenic shock, bridge to and following cardiac surgery, and more novel applications such as complex electrophysiologic mapping and ablation studies of unstable ventricular rhythms.
Sex differences in the distribution of axon types within the genu of the rat corpus callosum

Neuroanatomical sex differences have been documented in the rat neocortex, including dimorphism of its predominant commissure, the corpus callosum (CC). In particular, CC sex differences have been reported in the ultrastructure of the posterior callosal region, the splenium. Since the CC is a heterogeneous fiber tract with its axons arising from distinct cortical areas and passing through restricted regions along its length, it became of interest to ascertain whether cellular sexual dimorphisms may also be present in another division of the CC. To test this hypothesis, electron microscopy was used to examine axon composition in adult male and female rats in the anterior portion, the genu. The number and size of axons, the thickness of the myelin sheath, and the area within the genu occupied by these constituents, were quantified. Results showed a significant sex difference in the ratio of unmyelinated to myelinated axons, with females having a larger proportion of unmyelinated fibers. This effect was present for both (1) the number of axons, and (2) the area taken up by axonal fibers. No differences were found in the size of either axon type, or for myelin thickness. Comparison of these results with those from the splenium and possible mechanisms underlying this dimorphsim are discussed.
Identification of a developmental gradient of estrogen receptor expression and cellular localization in the developing and adult female rat primary somatosensory cortex

Abstract Immunohistochemistry was used to investigate the spatiotemporal distribution of estrogen receptor α and β (ERα, ERβ) in the posteromedial barrel subfield (PMBS) of the cerebral cortex in developing and adult female rats. Counting of immunopositive cells in predefined areas from each layer of the PMBS showed that at PN3, ERα immunoreactivity (IR) was present in every cell, whereas ERβ-IR was not detected. At PN6, about 59% of the cells were ERα immunopositive and low levels of ERβ-IR were observed in scattered cells. At PN18 the proportion of ERα-IR cells decreased to 49%; however, ERβ-IR became widespread and was detected in 39% of cells. By PN25 only faint ERα-IR was observed and in the adults ERα-IR was not detected. In contrast, at PN25 and in adults, ERβ-IR was detected in about half the cells of the PMBS. Regarding the cellular localization of ER-IR, at PN3 an outside-in gradient of cytoplasmic to nuclear localization of ERα-IR was observed. At PN18 and in adults ERβ-IR was preferentially localized to the nucleus of principal neurons, and to the cytoplasm of small, stellate-shaped interneurons. Together, these observations reveal a developmental transition of ER expression in the PMBS; ERα is expressed during early development, ERα and ERβ are co-expressed at later developmental times, and only ERβ is expressed in adults. These changes in ER expression and localization suggest that ERα and ERβ may play important, but different roles in the formation and function of the PMBS region of the primary somatosensory cortex.
Inhibitory control following perinatal brain injury.

Evidence from developmental, lesion, and neuroimaging studies indicates that the prefrontal cortex plays a major role in executive abilities, including inhibitory control. Proficient executive performance, however, relies not only on the integrity of the prefrontal cortex but also on its interactions with other brain regions. In the current study, the authors focused on the effect that early damage to the white matter tracts interconnecting prefrontal and other brain regions has on inhibitory control. Data were collected from 13 children with bilateral spastic cerebral palsy and from a control group of 20 children with no history of neurologic compromise. Converging evidence from 3 separate paradigms is presented that strongly suggests these children experience impairments in inhibitory control. Findings are discussed within the context of current cognitive and neuroanatomical models of inhibition. Executive ability is a broad term used to describe an assemblage of higher order cognitive abilities such as strategy use, cognitive flexibility, and inhibitory control (Pennington, 1997; Stuss, 1992). Although spanning a broad spectrum, all of these abilities require the efficient coordination and integration of information across a variety of sensory modalities and cognitive domains (e.g., visuoperceptual, language, and memory). From a neuroanatomical perspective, cognitive integration of this nature appears to be most heavily mediated by a common brain region, the prefrontal cortex (Stuss, Alexander, & Benson, 1997). Because the prefrontal cortex has numerous interconnections with other brain regions, it is well suited to support the synchronization of widely distributed neural activity (Cummings, 1995; Thatcher, 1997). The prefrontal cortex is the last brain region to reach maturity, with development continuing into early adulthood (Krasnegor, Lyon, & Goldman-Rakic, 1997). A particularly important aspect of prefrontal development, and the subsequent enhancement of executive abilities, is the refinement of intricate white matter connections between the prefrontal cortex and other brain regions. Thatcher (1997) suggested that the refinement of prefrontal connections stems from cyclical patterns of neural growth during which synapses are rapidly generated and then selectively pruned. The re
Patterned running as a function of the sequence of trial administration

Groups of S and T received 201 trials on a recursive RNN schedule of reinforcement. Group T, in which each S received its first daily trial before the first S received its second trial, etc., ran fast on R and slow on N trials. Group S, in which each S received all of its daily trials, before the second S received its first trial, ran fast, slow, fast on R, N1, and N2 trials, respectively.
The Role of Self-Regulation in Abstinence Maintenance: Effects of Communal Living on Self-Regulation

Studies of self-regulation suggested that self-control requires finite resources; this requirement, in turn, may present a significant challenge for those trying to recover from or control addictive behaviors. The present study examined the relationships between self-regulation and abstinence maintenance among adults in recovery (n = 606: 407 men, 199 women; M age = 38.5 years) residing in self-governed, communal-living, abstinent homes across the United States. Self-regulation scores (controlling for sex and age) were positively related to length of abstinence. In addition, a factor analysis of self-regulation scores resulted in some differentiation between general self-discipline and impulsivity in self-control related to addiction. The relationship between impulsivity and length of abstinence was stronger than the relationship derived between general self-regulation and length of abstinence.
Alternative male mating tactics in bembecinus quinquespinosus hymenoptera sphecidae correlations with size and color variation

The digger wasp Bembecinus quinquespinosus exhibits characteristics not typical of other species in the family Sphecidae: there is no sexual size dimorphism (Fig. 1) and there is a size-linked color polymorphism among males (Fig. 2). We studied a population of this species in eastern Colorado, USA to determine if the above attributes were related to the male mating strategy.
Hydrazine adsorption and decomposition on the GaAs(100)-c(8 × 2) surface

Abstract Temperature programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), and high resolution electron energy loss spectroscopy (HREELS) have been used to study the decomposition mechanism of hydrazine (N2H4) on the GaAs(100)-c(8 × 2) surface. Hydrazine adsorbs in a “side on” manner as indicated by XPS results. For small doses, hydrazine decomposition is complete, and the major decomposition product is ammonia, with nitrogen and hydrogen also being formed. For large doses, nitrogen is the major gas phase decomposition product. The absence of a high temperature atomic nitrogen recombination TPD peak indicates that nitrogen is made through an intramolecular mechanism. Both N2Hy and NHx species (y = 1, 2, 3; x = 1, 2) are identified as reaction intermediates. Above 350 K, only NHx species are present on the surface.
Full-wave electromagnetic modeling of terahertz RTD-gated HEMTs

Full-wave analysis has been extensively used in the past to model traveling-wave transistors. However, no design has incorporated resonant tunneling diode structures to assess their resonance and gain. In this investigation, finite element (frequency-domain) and finite-difference time-domain techniques are used to model the performance of a HEMT/RTD integrated structure. These structures are unique as they have the potential to resonate at terahertz frequencies. In this paper, an RTD-gated structure is designed and shown to deliver nearly 4 dB of gain.
Long-term treatment effects of vitamin E for tardive dyskinesia.

Abstract Background: Several studies have found that alpha-tocopherol (vitamin E) can effectively treat tardive dyskinesia (TD). A limitation of these trials is their short treatment durations (maximum of 12 weeks), which do not allow us to address the effects of long-term treatment. Methods: To participate, patients had to have TD and be on stable oral medications. The study enrolled 40 patients who received up to 36 weeks of treatment with d-vitamin E (1600 IU per day) or placebo. Results: Using the Abnormal Involuntary Movements Scale (AIMS) score (sum of items #1–7) to measure TD severity, the study found a significant difference (3 points) in mean AIMS scores, in favor of vitamin E, starting at 10 weeks of treatment and continuing through the full 36 weeks. We used linear mixed-effects regression to quantify the impact of several covariates, and found that treatment assignment, TD duration, and chlorpromazine equivalents had significant effects on decreasing the AIMS score. Conclusions: The study’s finding that vitamin E is effective in treating TD agrees with results from prior studies and provides evidence that the effect may extend to treatment of up to 36 weeks. These findings are in direct contrast to those of VA Cooperative Study #394, a much larger, long-term, multi-site study, conducted by many of the same investigators, in which Vitamin E was not superior to placebo (see Editorial in this issue).
Reality Without Reference

Summary A dilemma concerning reference is posed: on the one hand it seems essential, if we are to give an account of truth, to first give an account of reference. On the other hand, reference is more remote than truth from the evidence in behavior on which a radical theory of language must depend, since words refer only in the context of sentences, and it is sentences which are needed to promote human purposes. The solution which is proposed is to treat reference as a theoretical construct whose sole function is to serve a theory of truth. Since more than one relation between words and objects will serve a theory of truth equally well, this amounts to giving up the concept of reference as basic. Resume L'auteur pose un dilemme a propos de la reference: d'un cote, il semble essentiel, pour rendre compte de la verite, de tenir d'abord compte de la reference. D'autre part, la reference est plus eloignee que la verite du donne comportemental dont une theorie radicale du langage doit dependre, puisque les mots n'ont de reference que dans le contexte de phrases, et que ce sont les phrases dont on a besoin pour realiser les buts humains. La solution qui est proposee, c'est de traiter la reference comme une construction theorique dont la seule fonction est de servir a une theorie de la verite. Puisque plusieurs relations entre les mots et les objets rendront les memes services a une theorie de la verite, cela revient a renoncer a considerer le concept de reference comme un concept de base. Zusammenfassung Das Problem der Referenz stellt uns vor folgendes Dilemma: einerseits scheint eine Theorie der Wahrheit eine Theorie der Referenz vorauszusetzen, und andererseits ist Referenz einer behavioristischen Behandlung weniger unmittelbar zuganglich als Wahrheit. Auf eine solche Behandlung muss sich aber eine radikale Sprachtheorie abstutzen, da Worter nur im Kontext von Satzen sich auf etwas beziehen und da wir Satze benotigen, um unsere Zwecke voranzubringen. Die vorgeschlagene Losung besteht darin, die Referenz als ein theoretisches Konstrukt einzufuhren, das allein die Funktion hat, eine Grundlage fur die Wahrheitstheorie zu liefern. Da jedoch mehr als bloss eine Relation zwischen Wortern und Objekten in befriedigender Weise einer Wahrheitstheorie zugrundegelegt werden kann, bedeutet dies, dass wir die Referenz nicht mehr als fundamentalen Begriff betrachten.
NMR Measurement of Transient Phenomena in Liquid Crystals

Abstract A method for measuring the time dependence of molecular orientation is presented. The molecular orientation is obtained from the nuclear free induction decay using the method of moments. This technique is useful for measuring a variety of' transient phenomena with several application to liquid crystals.