cssi/SciSciGPT-SciSciNet huggingface dataset:
Enhancing the multi-functional properties of renewable lignin carbon fibers via defining the structure–property relationship using different biomass feedstocks

Lignin has been explored extensively as a renewable precursor for carbon materials, considering its abundance as a major component of plant cell walls and its sustainability as a byproduct of both lignocellulosic biorefinery and the paper-making industry. Despite the extensive efforts to define the process–property relationship, it remains largely unknown how lignin biosynthesis and its chemistry would impact the resultant carbon fiber properties, for both mechanical and electroconductive performances. Such inadequate understanding fundamentally limits feedstock design and selection to improve carbon fiber properties toward broader commercial applications. Using lignin from a broad range of biomass feedstocks for carbon fiber manufacturing, we have fundamentally explored the structure–function relationship between lignin chemistry and carbon fiber performance. Specifically, lignin extracted from hardwood (sugar maple), softwood (loblolly pine and red cedar), and herbaceous plants (corn stover and switchgrass) was used for carbon fiber manufacturing, considering the very different lignin structures from these feedstocks. Linear regression models were established to define the relationship between carbon fiber mechanical properties and lignin structural characteristics. The results highlighted that the content of β-O-4 linkages correlates significantly with the tensile strength and elastic modulus of lignin carbon fibers, indicating that more linear β-O-4 linkages would promote the carbon fiber mechanical performance. Moreover, electroconductive properties are essential for broader energy device application of lignin-based carbon fibers, yet the mechanisms controlling their electroconductivity are largely unknown. We hereby demonstrated that a higher β-O-4 content also promotes the electroconductivity of lignin carbon fibers. Microstructure analysis further revealed that the crystallite size and content of the pre-graphitic turbostratic carbon structure in lignin-based carbon fibers were enhanced as the β-O-4 linkages increased. The content of β-O-4 linkages has shown a strong correlation with the crystallite content in a linear regression model. This study thus revealed the underlying mechanisms regarding how the lignin structure in planta defines the resultant carbon fiber properties. Moreover, the study also highlighted the correlation between the mechanical and electroconductive properties of lignin-based carbon fibers, both of which were defined by the lignin structure.
Molecular dynamics simulations

Originally the province of theorists only, molecular dynamics simulations are now accessible to a broad range of scientists. Advances in methodology, coupled with the development of fast and relatively inexpensive computer workstations, have increased the efficiency, accuracy, reliability, and applicability of these methods. Crossing important research frontiers in biology demands understanding molecular function in mechanistic terms through structures, motions, and energetics. The new paradigm of genome science will also make extensive use of structural models to interpret sequence data. The creative application of molecular dynamics techniques will undoubtedly make substantial contributions to these studies.
Simulated changes to tropical cyclones across the Paleocene-Eocene Thermal Maximum (PETM) boundary

Abstract Tropical cyclones are an important meteorological and climatological process in Earth's climate system. These intense, localized storms mainly form over warm equatorial oceans, and propagate poleward. During their lifetime, tropical cyclones can strengthen leading to intense winds and rainfall events. These storms also carry moist energy that contribute to the poleward transport of atmospheric energy. Presently, concern exists about how the characteristics of tropical cyclones will change in a future warming world. The Paleocene Eocene Thermal Maximum (PETM) was a time in Earth's deep past in which the planet warmed by 5° - 8 °C due to an increase in atmospheric CO2. It is thus of interest to understand how past warming affected tropical cyclone behavior. Here, a high resolution (25 km) atmospheric model is used to study changes in tropical cyclones across the PETM boundary. Orbital variation is also investigated as an additional forcing mechanism at the time of the PETM. The climate simulations indicate that greenhouse forcing leads to a poleward shift in TCs, much like projected future scenarios and in simulations of other warm periods in Earth history. It is also found that the orbital forcing response is very different than the greenhouse cases due to the difference in thermal response, which, in turn, induces a different dynamical response in wind shear. Although the spatial pattern between changes across the PETM and the future differ, there are still many similarities in TC response for these two very different periods in time, indicating the robustness of the TC response to greenhouse warming.
Cellulonodin-2 and Lihuanodin: Lasso Peptides with an Aspartimide Post-translational Modification

Lasso peptides are a family of ribosomally synthesized and post-translationally modified peptides (RiPPs) defined by their threaded structure. Besides the class-defining isopeptide bond, other post-translational modifications (PTMs) that further tailor lasso peptides have been previously reported. Using genome mining tools, we identified a subset of lasso peptide biosynthetic gene clusters (BGCs) that are colocalized with protein L-isoaspartyl methyltransferase (PIMT) homologs. PIMTs have an important role in protein repair, restoring isoaspartate residues formed from asparagine deamidation to aspartate. Here we report a new function for PIMT enzymes in the post-translational modification of lasso peptides. The PIMTs associated with lasso peptide BGCs first methylate an L-aspartate sidechain found within the ring of the lasso peptide. The methyl ester is then converted into a stable aspartimide moiety, endowing the lasso peptide ring with rigidity relative to its unmodified counterpart. We describe the heterologous expression and structural characterization of two examples of aspartimide-modified lasso peptides from thermophilic Gram-positive bacteria. The lasso peptide cellulonodin-2 is encoded in the genome of actinobacterium Thermobifida cellulosilytica, while lihuanodin is encoded in the genome of firmicute Lihuaxuella thermophila. Additional genome mining revealed PIMT-containing lasso peptide BGCs in 48 organisms. In addition to heterologous expression, we have reconstituted PIMT-mediated aspartimide formation in vitro, showing that lasso peptide-associated PIMTs transfer methyl groups very rapidly as compared to canonical PIMTs. Furthermore, in stark contrast to other characterized lasso peptide PTMs, the methyltransferase functions only on lassoed substrates. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/444711v1_ufig1.gif" ALT="Figure 1"> View larger version (9K): org.highwire.dtl.DTLVardef@f0ed44org.highwire.dtl.DTLVardef@1694443org.highwire.dtl.DTLVardef@908forg.highwire.dtl.DTLVardef@112b2da_HPS_FORMAT_FIGEXP M_FIG C_FIG
Prevalence of advance care planning in a resident run clinic in an underserved community.

e24067Background: Advance Care Planning (ACP) ensures that patients receive care that is in line with their values and preferences. ACP is best done in the outpatient setting. Despite recognizing t...
Gender Differences in Impacts of Place-Based Neighborhood Greening Interventions on Fear of Violence Based on a Cluster-Randomized Controlled Trial.

Maintained green space in underserved urban neighborhoods may be an important environmental pathway to improving community health and safety, though effects may vary across population subgroups and by time of day. We examined survey responses from 442 participants (178 men and 264 women), living near vacant lots in a cluster-randomized controlled trial of a cleaning and greening intervention, on perceived safety during the day and at night. At the intervention sites after the intervention, only men reported feeling less unsafe during the day. Women reported more fear, and men reported less fear, after the intervention, although these results and tests for effect modification were not statistically significant. The clean-and-green intervention may have allayed fears for men during the day and supported their ease of movement throughout their neighborhoods. However, at night, it may have had the opposite effect on women. Though our study was under-powered, not designed to test associations stratified by gender, directions and magnitudes of associations differed substantially, indicating a need for further investigations into potential gender differences in the benefits of green space, to inform and better tailor interventions to improve perceived safety for all.
Accounting for Risk

This monograph reports on developing research that assesses the risk of equity investing from financial statements. The relevant information is conveyed by accounting numbers generated under accounting principles that respond to risk and its resolution, namely the realization principle and conservative accounting for investment. The recognition of this information leads to a financial statement analysis that extracts the risk information, to a reevaluation of performance metrics, and to revisions in risk factor models in asset pricing that utilize accounting information. The research also has implications for accounting-based valuation and for accounting standards that provide information for valuation and equity investing.
The Hormonal Milieu in Obesity and Influences on the Trabecular, Cortical, and Geometric Properties of Bone

Obesity is associated with alterations in several endocrine factors, some of which are involved in regulating bone metabolism. The higher serum concentrations of parathyroid hormone (PTH), estradiol, pancreatic hormones, and adipokines such as leptin, resistin, and cytokines and the lower 25-hydroxyvitamin D (25OHD) have specific actions on the skeleton and regulate cortical and trabecular bone differently. Recent evidence suggests that bone quality is altered in obesity with a higher trabecular volumetric bone mineral density (vBMD), while cortical vBMD is lower. Also, the obese are at greater risk of fracture for a given BMD compared to normal weight individuals supporting the evidence that bone quality is altered due to excess adiposity. Higher concentrations of serum PTH have a catabolic effect on cortical bone and may play a role in reducing cortical vBMD in obesity. The lower serum 25OHD, higher leptin and resistin, and lower adiponectin may also independently contribute to the lower cortical vBMD in obesity. There is little evidence to show that higher pancreatic hormones and cytokines influence trabecular and cortical bone in obesity. The altered hormonal milieu in obesity is one important factor that explains bone architectural changes that occur due to excess adiposity. However, other factors such as diet, genetic factors, altered mechanical loading, and/or other environmental factors may also contribute to bone quality and site-specific fracture risk in obesity.
Predictors of mortality, hospital utilization, and the role of race in outcomes in head and neck trauma.

Objective A retrospective cross-sectional analysis was undertaken to determine the impact of race and insurance status on trauma outcomes in patients admitted to a Level I trauma center following head and neck fractures. Study Design Putative predictive factors, including injury mechanism, hemorrhagic shock, injury severity score (ISS), race, gender, and insurance status, were used in a multivariate outcome analysis to determine their influence on length of hospital stay, number of procedures performed, discharge status, and mortality; P Results Proportionately more male patients (76.5%) sustained head and neck fractures compared with females (23.5%). Blacks and Hispanics sustained proportionately more gunshot wounds (GSWs) compared with Whites, 16:1 and 7:1, respectively. There were no significant differences in length of hospital stay and mortality based on race or insurance status. Mortality was related to age, GSW as a mechanism of injury, increasing ISS, and shock on admission. Conclusions Minority race and insurance status did not correlate with worse outcomes. Treatment biases in the acutely injured patient with head and neck injuries may be less prevalent than thought, if we consider mortality and utilization of care as primary outcome measures.
Real analytic solutions of parabolic equations with time-measurable coefficients

We use Bernstein's technique to show that for any fixed t, strong solutions u(t, x) of the uniformly parabolic equation Lu:= a ij (t)u xix -ut = 0 in Q are real analytic in Q(t) = {x: (t, x) ∈ Q}. Here, Q ⊂ R d+1 is a bounded domain and the coefficients a ij (t) are measurable. We also use Bernstein's technique to obtain interior estimates for pure second derivatives of solutions of the fully nonlinear, uniformly parabolic, concave equation F(D 2 u, t)-u t = 0 in Q, where F is measurable in t.
A geometrical characterization of a class of holomorphic vector bundles over a complex torus

This note is to be a supplement of the preceeding paper in the journal by Matsushima, settling a question raised by him. In his paper he associates a holomorphic vector bundle over a complex torus to a holomorphic representation of what he calls Heisenberg group. We shall show that a simple holomorphic vector bundle is determined in this manner if and only if the associated projective bundle admits an integrable holomorphic connection. A theorem by Morikawa ([3], Theorem 1) is the motivation of this problem and is somewhat strengthened by our result.
Mast cell‐cholinergic nerve interaction in mouse airways

We addressed the mechanism by which antigen contracts trachea isolated from actively sensitized mice. Trachea were isolated from mice (C57BL/6J) that had been actively sensitized to ovalbumin (OVA). OVA (10 μg ml−1) caused histamine release (∼70% total tissue content), and smooth muscle contraction that was rapid in onset and short-lived (t1/2 < 1 min), reaching approximately 25% of the maximum tissue response. OVA contraction was mimicked by 5-HT, and responses to both OVA and 5-HT were sensitive to 10 μm-ketanserin (5-HT2 receptor antagonist) and strongly inhibited by atropine (1 μm). Epithelial denudation had no effect on the OVA-induced contraction. Histological assessment revealed about five mast cells/tracheal section the vast majority of which contained 5-HT. There were virtually no mast cells in the mast cell-deficient (sash−/−) mouse trachea. OVA failed to elicit histamine release or contractile responses in trachea isolated from sensitized mast cell-deficient (sash−/−) mice. Intracellular recordings of the membrane potential of parasympathetic neurons in mouse tracheal ganglia revealed a ketanserin-sensitive 5-HT-induced depolarization and similar depolarization in response to OVA challenge. These data support the hypothesis that antigen-induced contraction of mouse trachea is epithelium-independent, and requires mast cell-derived 5-HT to activate 5-HT2 receptors on parasympathetic cholinergic neurons. This leads to acetylcholine release from nerve terminals, and airway smooth muscle contraction.
Steady state hydrogen transport in solids exposed to fusion reactor plasmas: Part I: Theory☆

Abstract A simple analytical transport parameter formalism is presented for evaluating the steady state hydrogen (tritium) inventory, recycle rate, and permeation rate for surfaces exposed to the plasma of an operating magnetic confinement fusion reactor. The formalism includes hydrogen trapping, recombination barriers to release at inner and outer surfaces, diffusion, and effects of thermal gradients (e.g., Ludwig-Soret effect). The transport parameter concept results in a natural classification of the transport behavior of hydrogen in all materials at temperatures for which the solutionized hydrogen is mobile. The analytical results provide physical insight into the processes governing hydrogen permeation and inventory and also allow simple checks on the accuracy of numerical calculations which must be used at early times in the buildup to steady state operation.
Treatment of Chronic Dacryocystitis

This paper prepared by cooperation of the Sections on Ophthalmology and on Otology, Laryngology and Rhinology of the Mayo Clinic includes a general discussion of the subject and the description of a preferred method of operation.
Chiroptical properties of 2-substituted pyrrolidines

Abstract The CD spectra of L-2-methylpyrrolidine, L-prolinol, and their N-methylated derivatives have been determined. As in the 2-substituted piperidines, N-methylation results in an inversion of the sign of the Cotton effects (CE). However, the sign of the long-wavelength CE does not follow the simple helicity rule found for 2-substituted piperidines, since the pyrrolidine ring is itself chiral and makes its own contributions to the observed CE's. The rotational contribution due to pyrrolidine ring chirality appears to be opposite in sign to and larger in magnitude than that due to the 2-substituent in both the secondary and the tertiary amines.
Isolation of an acidic pigment in Neurospora

Abstract The major component of the acidic pigments of Neurospora was isolated by chromatography and crystallization. Absorption spectra are given for 1% solutions in different solvents. The name neurosporaxanthin is proposed for this carotenoid.
The organization of ideological diversity in discourse: Modern and neotraditional visions of the Tongan state

In current cultural anthropology, under the influence of postmodernism, considerable attention is given to the multiplicity of interpretive perspectives with which people contend in making sense of their daily experiences. In this article I examine diverse representations of the nation-state in Tonga and other Pacific microstates. My focus is on the configuration of ideological diversity in the Tongan Magistrate's Courts compared with configurations of traditional and modern nationalist ideologies in other Tongan political domains and in other Pacific nations. Some contemporary anthropological accounts represent ideological diversity as plural, fluid, and rapidly changing. Other accounts of ideological diversity emphasize the oppositional structuring of ideas and the power struggle for ideological domination. I argue that it is useful to think of an ecology of ideas, in which multiple ideas move across discourse domains, becoming implanted in hospitable discourse environments, much as plants move into new environments.
Quantum nucleation and thermal activation of vortex rings in high-Tc superconductors.

Vortex-ring nucleation by thermal activation and quantum-tunneling processes in high-${\mathit{T}}_{\mathit{c}}$ superconductors is discussed. The nonlinear resistance scales as ${\mathit{e}}_{\ensuremath{\nu}}^{\mathrm{\ensuremath{-}}(\mathit{J}}$/J${)}^{\ensuremath{\nu}}$. Thermal activation yields a critical index of \ensuremath{\nu}=1, while quantum tunneling (without normal current dissipation) yields a critical index of \ensuremath{\nu}=2. Current-voltage characteristics were measured on both disordered (low-${\mathit{J}}_{\mathit{c}}$), ordered (c axis normal to the film plane, high-${\mathit{J}}_{\mathit{c}}$) Y-Ba-Cu-O films, and microbridges below ${\mathit{T}}_{\mathit{c}}$. The data were examined in terms of both thermal-activation and quantum-nucleation models. For the disordered films, the \ensuremath{\nu}=1 scaling law is in reasonable agreement with data, while \ensuremath{\nu}=2 scaling is required to explain the results of the ordered films at low temperatures. For the microbridges, the \ensuremath{\nu}=2 scaling extends even to high temperatures.
Cardiovascular reactivity during positive and negative marital interactions

Marriage reduces risk of cardiovascular disease (CVD) but marital stress increases risk, perhaps through cardiovascular reactivity (CVR). However, previous studies have lacked controls necessary to conclude definitively that negative marital interactions evoke heightened CVR. To test the specific effects of marital stress on CVR, 114 couples engaged in positive, neutral, or negative interactions in which speaking and task involvement were controlled. Compared to positive and neutral conditions, negative discussions evoked larger increases in systolic blood pressure, heart rate, and cardiac output, and larger decreases in peripheral resistance and pre-ejection period—similarly for men and women. Hence, CVR could contribute to the effects of marital difficulties on CVD. Previous evidence of sex differences in this effect might reflect factors other than simple reactivity to negative interactions.
Petrographic analysis of the Rosebud seam at the Absaloka, Big Sky, and rosebud mines, powder river basin, Montana

Abstract Analysis of maceral and mineral content and huminite reflectance for the Rosebud coal at the Absaloka, Big Sky, and Rosebud mines provides information on the variation of coal composition and rank probably caused by variation in depositional environments and coalification. Humanite reflectance indicates that rank is gradational from lignite at the Absaloka and Rosebud mines to subbituminous C at the Big Sky mine. Amounts of minerals and huminite, inertinite, and liptinite group macerals vary vertically at Absaloka and Big Sky, defining lithologic layers and suggesting changes in type and style of peat accumulation. Direct correlation of huminite reflectance with huminite abundance and inverse correlation with inertinite abundance suggests a possible relationship with coalification, depositional environment, and/or original floral characters. Depositional environment is initially interpreted as a swamp with mixed vegetation, or a swamp alternating from arboreal to herbaceous vegetation.
Existence and Stability of Traveling Fronts in the Extended Fisher-Kolmogorov Equation

Abstract We study traveling wave solutions to a general fourth-order differential equation that is a singular perturbation of the Fisher–Kolmogorov equation. We apply the geometric method for singularly perturbed systems to show that for every positive wavespeed there exists a traveling wave. Also, we find that there exists a critical wavespeed c * which divides these solutions into monotonic ( c ⩾ c *) and oscillatory ( c c *) solutions. We show that the monotonic fronts are locally stable under perturbations in appropriate weighted Sobolev spaces by using various energy functionals.
Racial Differences in the Fate of Melanosomes in Human Epidermis

MELANIN pigment in the skin is located in a very small granule, the melanosome1, which is barely visible in the light microscope. This melanosome is formed in the melanocyte and is transferred into the keratinizing or malpighian cell2.
Evaluation Of Multi-Spectral Linear Array Detectors For Spaceborne Applications

A NASA laboratory for evaluating linear detector arrays for remote sensing applications from the visible to shortwave infrared is described. Nominal requirements are presented on the critical parameters of signal-to-noise ratio, modulation transfer function, response linearity, dynamic range, and detector-to-detector response uniformity. Results of tests on a custom developed multi-spectral linear array from RCA and two commercial arrays from Texas Instruments and Reticon for the visible and near-infrared are presented. The custom array was clearly superior in signal-to-noise ratio and dynamic range to its off-the-shelf counterparts. Allthe arrays were found to have somewhat less than desirable modulation transfer functions, but excellent response linearity.
Adolescents and eating disorders: An examination of a day treatment program

Objective: In this study, we report on our day treatment program (DTP) for adolescents and young adults with eating disorders (EDs). Method: Data for the 82 female patients in DTP were examined, compared across ED diagnosis and by age (adolescents vs. young adults). At admission, patients completed the Eating Disorder Inventory-2 (EDI-2) and the Beck Depression Inventory (BDI) and the Family Adaptability and Cohesion Evaluation Scale- II (FACES-II). Results: Forty-nine percent of patients successfully completed the day program and 13% required hospitalization following day treatment. Overall, there were no significant differences between the adolescents and adults at discharge of the day program. Discussion: With shortened inpatient (IP) hospitalizations, DTPs can provide the long-term care required by many adolescent patients for psychological and physical recovery. This may be particularly important for the development of children and adolescents.
Refining a Jagged Edge

In a recent Cell Reports article, Chillakuri and colleagues showed that the N-terminal "MNNL" domain of the essential Notch ligand Jagged1 resembles a C2 domain and relies on calcium binding to facilitate productive signal transduction.
123I research and production at Brookhaven National Laboratory

Abstract The procedures for preparing high purity 123 I at the Brookhaven Linac Isotope Producer using the 127 I(p, 5n) 123 Xe reaction on a NaI target are described. The activity is supplied in a glass ampoule with anhydrous 123 I deposited on the interior walls, allowing maximum flexibility in subsequent iodinations. Preliminary experience with a continuous flow target is also described. The results of a series of measurements of specific activity by neutron activation, x-ray fluorescence, u.v. absorption, and wet chemistry generally showed no detectable carrier. HPLC methods to analyze the chemical form of radioiodine and to characterize various iodinated radiopharmaceuticals have been developed. These methods provide higher sensitivity, speed and resolution than commonly used techniques.
Note on the potential of ionized impurities in semiconductors

Abstract The theory of the potential of an impurity ion in a semiconductor is reconsidered by extending the original treatment of Dingle and Mansfield which resulted in a screened Coulomb potential. This simple form was obtained by using an approximation; namely, first expanding the Fermi-Dirac integral in terms of the ion potential and then discarding terms higher than linear. In the present treatment a modified ion potential is derived by retaining also the quadratic term in the expansion of the Fermi-Dirac integral. The modified potential is expressed as a product of the Dingle-Mansfield potential and a correction factor. At any distance from the impurity ion the correction factor is found to have a maximum as a function of charge carrier concentration. It is concluded that the screened Coulomb potential approximates well the potential of an impurity ion in the semiconductor since, in that range of distance from the ion which is important for scattering problems, its magnitude is only a few percentage ...
Management of nutritional and infectious complications of postoperative chylothorax in children

Postoperative chylothorax may occur following any intrathoracic surgical procedure in children. From January 1979 through February 1987, 18 children aged 1 month to 9 years had chylothorax listed among their discharge diagnoses. Initial therapy for all patients consisted of chest tube placement for pleural space drainage and nutritional support with either enteral formulas enriched with medium-chain triglycerides or total parenteral nutrition. Both total parenteral nutrition and medium-chain triglyceride-enriched enteral regimens provided adequate nutritional support in these children. Five of the 18 experienced lymphopenia secondary to chylous lymphocyte loss. Infections were diagnosed in 5 patients during hospitalization; one was a fatal viral pneumonitis. No correlation between infectious complications and lymphocyte count could be demonstrated.
Effects of CuCl2 on the hydrolysis of cyclic GMP and cyclic AMP by the activator-dependent cyclic nucleotide phosphodiesterase from bovine heart.

In the presence of 10 micrometer Ca2+ and 5 mM Mg2+ (or 0.25 mM Mg2+), the addition of 100 micrometer Zn2+, Ni2+, Co2+, Fe2+, Cu2+ or 1 mM Mn2+ resulted in varying degrees of stimulation or inhibition of 10(-6) M cyclic GMP and cyclic AMP hydrolysis by the activator-dependent cyclic nucleotide phosphodiesterase from bovine heart in the absence or presence of phosphodiesterase activator. The substrate specificity of the enzyme was altered under several conditions. The addition of Zn2+ in the presence of 5 mM Mg2+ and the absence of activator resulted in the stimulation of cyclic GMP hydrolysis over a narrow substrate range while reducing the V 65% due to a shift in the kinetics from non-linear with Mg2+ alone to linear in the presence of Zn2+ and Mg2+. Zn2+ inhibited the hydrolysis of cyclic GMP and cyclic AMP in the presence of activator with Ki values of 70 and 100 micrometer, respectively. Zn2+ inhibition was non-competitive with substrate, activator and Ca2+ but was competitive with Mg2+. In the presence of 10 micrometer Ca2+ and activator, a Ki of 15 micrometer for Zn2+ vs. Mg2+ was noted in the hydrolysis of 10(-6) M cyclic GMP. Several effects of Zn2+ are discussed which have been noted in other studies and might be due in part to changes in cyclic nucleotide levels following phosphodiesterase inhibition.
Metal-semiconductor-metal (MSM) photodetectors based on single-walled carbon nanotube film-silicon Schottky contacts

We fabricate and experimentally characterize metal-semiconductor-metal (MSM) photodetectors with CNT film Schottky electrodes on n -type and p-type silicon substrates. We extract a Schottky barrier height of ~0.45 eV and ~0.51 eV for CNT films on n -type and p-type Si respectively. The extracted barrier height corresponds to a CNT film workfunction of 4.5-4.7 eV, which is within the range of the previously reported workfunction values for individual CNTs. Furthermore, we find that while at temperatures above 240°K thermionic emission is the dominant transport mechanism, at lower temperatures tunneling begins to dominate. We also characterize the photoresponse of the CNT film-Si MSM photodetector by illuminating the samples with a 633 nm HeNe laser. We observe that while the photocurrent of the CNT film MSM devices is similar to that of the Ti/Au control samples at high biases, their lower dark current results in a higher photo-to-dark current ratio relative to the control devices. We explain these observations by comparing the two interfaces. This work opens up the possibility of integrating CNT films as transparent and conductive Schottky electrodes in conventional semiconductor electronic and optoelectronic devices.
Retrovirus-Induced Lymphoproliferation as a Model for Developing Diagnostic Criteria for Malignant Lymphoma in Mice

Several methods for evaluating lymphoproliferative lesions in mice were compared. The model systems included spontaneous lymphomas arising in CWD mice and NFS mice congenic for ecotropic murine leukemia virus (MuLV) induction loci and a series of transplants in mice with severe combined immunodeficiency disease mutation of cells derived from mice infected with LP-BM5 MuLV. Primary lymphomas and donor tissues and transplants were examined using histopathology, flow cytometry, and Southern blot analysis of DNA for rearrangements of immunoglobulin and T-cell receptor genes and for viral integrations. The use of flow cytometric analysis, to establish cell lineage and define population size, and DNA analysis, for cell lineage and clonality determination, allowed the identification of malignant lymphoproliferations. Histologic evaluation did not define clonal populations of particular lineage but did provide other indications of malignancy such as invasiveness and presence of a dominant morphologic cell type. Thus, the precision of diagnosis of mouse lymphomas can be considerably enhanced by augmenting histopathologic examination with antigenic and molecular characterizations that can define malignant populations.
Effect of Calcination Temperature on the Photocatalytic Reduction and Oxidation Processes of Hydrothermally Synthesized Titania Nanotubes

Titania nanotubes having diameters 8 to 12 nm and lengths of 50−300 nm were prepared using a hydrothermal method. Further, the titania nanotubes were calcined over the temperature range 200−800 °C in order to enhance their photocatalytic properties by altering their morphology. The calcined titania nanotubes were characterized by using X-ray diffraction and surface area analysis and their morphological features were studied by scanning and transmission electron microscopy. Nanotubes calcined at 400 °C showed the maximum extent of photocatalyitc reduction of carbon dioxide to methane, whereas samples calcined at 600 °C produced maximum photocatalytic oxidation of acetaldehyde. Electron paramagnetic resonance (EPR) spectroscopy was used to interrogate the effects of nanotube structure on the charge separation and trapping as a function of calcination temperature. EPR results indicated that undercoordinated titania sites are associated with maximum CO2 reduction occurring in nanotubes calcined at 400 °C. Des...
Getting around cosmic variance

Cosmic microwave background (CMB) anisotropies probe the primordial density field at the edge of the observable Universe. There is a limiting precision (“cosmic variance”) with which anisotropies can determine the amplitude of primordial mass fluctuations. This arises because the surface of last scatter (SLS) probes only a finite two-dimensional slice of the Universe. Probing other SLS's observed from different locations in the Universe would reduce the cosmic variance. In particular, the polarization of CMB photons scattered by the electron gas in a cluster of galaxies provides a measurement of the CMB quadrupole moment seen by the cluster. Therefore, CMB polarization measurements toward many clusters would probe the anisotropy on a variety of SLS's within the observable Universe, and hence reduce the cosmic-variance uncertainty.
The combined influence of substrate elasticity and ligand density on the viability and biophysical properties of hematopoietic stem and progenitor cells.

Hematopoietic stem cells (HSCs) are adult stem cells with the capacity to give rise to all blood and immune cells in the body. HSCs are housed in a specialized microenvironment known as the stem cell niche, which provides intrinsic and extrinsic signals to regulate HSC fate: quiescence, self-renewal, differentiation, mobilization, homing, and apoptosis. These niches provide a complex, three dimensional (3D) microenvironment consisting of cells, the extracellular matrix (ECM), and ECM-bound or soluble biomolecules that provides cellular, structural, and molecular signals that regulate HSC fate decisions. In this study, we examined the decoupled effects of substrate elasticity, construct dimensionality, and ligand concentration on the biophysical properties of primary hematopoietic stem and progenitor cells (HSPCs) using homologous series of two and three dimensional microenvironments. Microenvironments were chosen to span the range of biophysical environments presented physiologically within the bone marrow, ranging from soft marrow and adipose tissue ( 30 kPa). We additionally investigated the influence of collagen ligand density on HSPC biophysical parameters and compared these behaviors to those observed in HSPCs grown in culture on stiff glass substrates. This work suggests the potential for substrate stiffness and ligand density to directly affect the biophysical properties of primary hematopoietic stem and progenitor cells at the single cell level and that these parameters may be critical design criteria for the development of artificial HSC niches.
Between-hole acoustic surveying and monitoring of a granitic rock mass

The purpose of this technical note is to present preliminary results of an acoustic monitoring study performed as part of a comprehensive rock mechanic and geophysics research program (Ref.20) associated with large-scale heater tests in an abandoned iron-ore mine in central Sweden. The investigation was performed in a fractured granitic rock mass at a sub-surface depth of 340 m, in a drift adjacent to the original iron-ore mine workings. Acoustic monitoring took place between four empty, dry, vertical boreholes of 10 m depth spaced in the vicinity of a vertical heater borehole in the floor of a drift.
Suppression of tunneling by interference in half-integer-spin particles.

Within a wide class of ferromagnetic and antiferromagnetic systems, quantum tunneling of magnetization direction is spin-parity dependent: it vanishes for magnetic particles with half-integer spin, but is allowed for integer spin. A coherent-state path-integral calculation shows that this topological effect results from interference between tunneling paths.
Controlled Ventilation Enhances Catheter Stability During Radiofrequency Ablation

Variations in the amplitude of the atrial and ventricular depolarization waves of the intracardiac electrogram occur during different phases of respiration. Therefore, we tested whether controlled ventilation would reduce ablation attempts and increase the rate of success in patients undergoing radiofrequency ablation with general anesthesia. Thirty-eight children were divided into two groups: (1) controlled and (2) noncontrolled or cyclic ventilation. In the controlled ventilation group, the mapping electrogram was recorded during sustained inspiration, sustained expiration, and cyclic ventilation. Ablation was done in the phase of ventilation that had the least variability in atrial and ventricular amplitudes. Seventeen patients in the controlled ventilation group had tracings adequate for review. In eight patients, ablation was done during sustained inspiration with the percentage change of atrial and ventricular amplitudes (15% +/- 16% and 13% +/- 16%, respectively) being < that during sustained expiration (38% +/- 27%, P = 0.04 and 20% +/- 21%) or during cyclic ventilation (57% +/- 27%, P < 0.01 and 54% +/- 26%, P = 0.003). In nine patients, ablation was done during sustained expiration with the percentage change of atrial and ventricular amplitudes (5% +/- 5% and 5% +/- 2%) being less than that during sustained inspiration (21% +/- 14%, P = 0.01 and 11% +/- 6%, P = 0.01) or during cyclic ventilation (68% +/- 23%, P < 0.001 and 48 +/- 26%, P = 0.001). We achieved success with each patient in both groups, but the number of ablation attempts were less in the controlled ventilation group 1 (3 +/- 2), as compared to the cyclic ventilation group 2 (8 +/- 8; P < 0.02). We concluded that controlled ventilation reduced the number of ablation attempts and facilitated the ablation procedure.
Computation-rate-distortion in transform coders for image compression

We consider the computational complexity of block transform coding and tradeoffs among computation, bit rate, and distortion. In particular, we illustrate a method of coding that allows decompression time to be traded with bit rate under a fixed quality criteria, or allows quality to be traded for speed with a fixed average bit rate. We provide a brief analysis of the entropy coded infinite uniform quantizer that leads to a simple bit allocation for transform coefficients. Finally, we consider the computational cost of transform coding for both the discrete cosine transform (DCT) and the Karhunen-Loeve transform (KLT). In general, a computation-rate- distortion surface can be used to select the appropriate size transform and the quantization matrix for a given bandwidth/CPU channel.
An analysis of interdependent decisions

Abstract A conditional analytic technique for evaluating interdependent decisions, based on Bellman's ‘Principle of Optimality’ is proposed. The procedure computes both the present and future impacts of a decision and permits: (1) each decision to be evaluated independently; (2) an accurate and more informative evaluation of such decisions relative to existing evaluative schemes; and (3) important insights regarding the decision process, such as the employed planning horizon, the degree of choice conservatism, and whether and to what degree learning occurs. A nontime-staged assignment problem and time-staged production planning problem are used to illustrate its potential utility and generalizeability. The implications of the technique for evaluating non-programmable (e.g. managers) and programmable (e.g. heuristic) decisions as well as for designing organizational planning and control systems are discussed.
Feature selection for diagnosis of vectorcardiograms

The automatic classification of vectorcardiograms and electrocardiograms into disease classes using computerized pattern recognition techniques has been a much studied problem. To date, however, no system exists which meets desired accuracy and noise immunity requirements and development of new techniques continues. An important aspect of the problem is that of feature selection, in which the functions of data reduction and information preservation are performed. In this paper, the problem of linear feature extraction is studied and a modified form of the Karhunen-Loeve expansion is developed which appears to have some advantages for the present application. Comparison with other feature selection methods is made using a two-dimensional example. Finally, some areas for future research are pointed out.
Forensic psychiatry: anatomy of a service.

Abstract An examination of an urban forensic service over a 22 year period was undertaken by reviewing the records of 1195 defendants admitted. This revealed an increasing referral of violent and youthful defendants. Referral rates were highest for homicide. The prominent diagnosis seen was antisocial personality (27%), while schizophrenia (16%) was the next most common diagnosis. The reports to the court indicate an increasing tendency toward a finding of competency to stand trial as a result of increasing pretrial treatment. These data are compared to reports for other English-speaking forensic services and a correlation between admissions of schizophrenic defendants and a tendency toward relatively minor criminal offenses is seen.
Verifying irreducibility and continuity of a nonlinear time series

When considering the stability of a nonlinear time series, verifying aperiodicity, irreducibility and smoothness of the transitions for the corresponding Markov chain is often the first step. Here, we provide reasonably general conditions applicable to nonlinear autoregressive time series, including many with nonadditive errors.
Functional observer and state feedback

In this paper, relations between the designs of functional observers and state feedback in the state space and transfer function approaches are presented. If the state space description of the plan can be written in a controllable canonical form, we show that the state space approach of the functional observer and state feedback design can be transformed in the transfer function approach form, Once the equations in the transfer function approach are solved, all unknown elements in the equations of the state space approach can be computed by an iterative algorithm. Thus, the relationship between the two approaches is established. We shall also show that the transfer function approach has fewer restrictions.
The Impact of a ‘‘Low-Intensity’’ Versus ‘‘High-Intensity’’ Medical Intensive Care Unit on Patient Outcomes in Critically Ill Veterans:

Objective: To determine whether a low-intensity versus high-intensity medical intensive care unit (MICU) format in a Veterans Affairs (VA) hospital setting improves patient outcomes, as measured by...
Axial pairs and convergence groups on S1

Abstract We prove that group G of homeomorphisms of S 1 will be a convergence group if it satisfies a finiteness condition which is satisfied by Fuchsian groups.
Experiments Toward Fundamental Validation of PEM Fuel Cell Models

Detailed experimental parameters are controlled and measured under widely varying operating conditions. In addition to polarization curves, feed gas flow rates, temperatures, pressure drop, and relative humidity are all measured accurately. Performance of a polymer electrolyte fuel cell (PEFC) was studied using steady-state polarization curves and electrochemical impedance spectroscopy (EIS) techniques. The effects of relative humidity, temperature, pressure and feed gas stoichiometry on fuel cell performance were investigated. It was found that the humidity of both the anode and cathode inlet gases had a significant effect on fuel cell performance. The experimental results showed that a decrease in the cathode humidity has a more detrimental effect on cell performance than a comparable decrease in the anode humidity. The obtained results will be used to define conditions of optimal hydration of the membrane. Based on the performance and resistance measurements, optimal humidification can be achieved. The polarization curves of the cell at different operating temperatures showed that fuel cell performance was improved with increasing temperature from 65 to 75°C. The fuel cell performance also improved as the operating pressure was increased from 1 atm to 4 atm. The resistance of the working fuel cell showed that the membrane resistance increased as the feed gas relative humidity (RH) decreased. The experimental results were compared with the results of a CFD mathematical model. These experimental data will provide a baseline for validation of fuel cell models.Copyright © 2005 by ASME
1,4-Dioxobenzene Compounds of Gallium: Reversible Binding of Pyridines to [{(tBu)2Ga}2(μ-OC6H4O)]n in the Solid State

The gallium aryloxide polymer, [[((t)Bu)(2)Ga](2)(mu-OC(6)H(4)O)](n)(1) is synthesized by the addition of Ga((t)()Bu)(3) with hydroquinone in a noncoordinating solvent, and reacts with pyridines to yield the yellow compound [((t)()Bu)(2)Ga(L)](2)(mu-OC(6)H(4)O) [L = py (2), 4-Mepy (3), and 3,5-Me(2)py (4)] via cleavage of the Ga(2)O(2) dimeric core. The analogous formation of Ga((t)()Bu)(2)(OPh)(py) (5) occurs by dissolution of [((t)Bu)(2)Ga(mu-OPh)](2) in pyridine. In solution, 2-4 undergo dissociation of one of the pyridine ligands to yield [((t)()Bu)(2)Ga(L)(mu-OC(6)H(4)O)Ga((t)Bu)(2)](2), for which the DeltaH and DeltaS have been determined. Thermolysis of compounds 2-4 in the solid-state results in the loss of the Lewis base and the formation of 1. The reaction of 1 or [((t)Bu)(2)Ga(mu-OPh)](2) with the vapor of the appropriate ligand results in the solid state formation of 2-4 or 5, respectively. The deltaH and deltaS for both ligand dissociation and association for the solid-vapor reactions have been determined. The interconversion of 1 into 2-4, as well as [((t)Bu)(2)Ga(mu-OPh)](2) into 5, and their reverse reactions, have been followed by (13)C CPMAS NMR spectroscopy, TG/DTA, SEM, EDX, and powder XRD. Insight into this solid-state polycondensation polymerization reaction may be gained from the single-crystal X-ray crystallographic packing diagrams of 2-5. The crystal packing for compounds 2, 3, and 5 involve a head-to-head arrangement that is maintained through repeated ligand dissociation and association cycles. In contrast, when compound 4 is crystallized from solution a head-to-tail packing arrangement is formed, but during reintroduction of 3,5-Me(2)py in the solid state-vapor reaction of compound 1, a head-to-head polymorph is postulated to account for the alteration in the deltaH of subsequent ligand dissociation reactions. Thus, the deltaH for the condensation polymerization reaction is dependent on the crystal packing; however, the subsequent reversibility of the reaction is dependent on the polymorph.