cssi/SciSciGPT-SciSciNet huggingface dataset:
Some effects of phonon dynamics on electron lifetime, mass renormalization, and superconducting transition temperature

Effects of the dynamical properties of phonons on the electronic properties of metals are treated through the use of the phonon spectral weight function. It is shown that the leading behavior of the electron quasiparticle lifetime is lowered to quadratic in the frequency or temperature from the cubic behavior which is well known to occur for infinitely sharp phonons. Explicit evaluations of $\frac{1}{\ensuremath{\tau}}$ are made using an extension of the Debye model which allows for a finite phonon lifetime. The mass-enhancement parameter $\ensuremath{\lambda}$ is discussed and is shown formally to be related to the static phonon propagator. Thus if there is a difference between the phonon relaxation at zero frequency and at the phonon frequency, it is possible for the phonon frequencies which determine $\ensuremath{\lambda}$ to differ significantly from the peak frequencies observed in inelastic neutron scattering. The implications of these results for superconducting transition temperatures are discussed with particular reference to recent neutron scattering experiments in ${\mathrm{Nb}}_{3}$Sn.
Protection of the allylic alcohol double bond from catalytic reduction in the preparation of [1-3H]morphine and [1-3H]codeine

The t-butyldimethylsilylation of the allylic alcohol of 1-iodomorphine and 1-iodocodeine protects the double bond of these molecules from catalytic reduction while allowing the reduction of the aryl iodide. This selectivity has been applied to the preparation of tritiated morphine and codeine without complicating over reduction to the dihydromorphine and dihydrocodeine. © 1998 John Wiley & Sons, Ltd.
Calcium‐Activated Neutral Proteinases as Regulators of Cellular Function Implications for Alzheimer's Disease Pathogenesis

Evidence is emerging that calcium-activated neutral proteinases (CANPs) not only participate in intracellular protein turnover but help to regulate the functional reorganization of cytoskeletal proteins in response to calcium and second-messenger stimulation. The high concentration of CANPs in certain neurons has suggested prominent roles for this proteolytic system in neuronal and synaptic function. In addition to acting directly on specific constituents of the cytoplasmic and membrane-associated cytoskeletal networks, CANP may amplify its effects by modulating the activities of protein kinase C and possibly other kinases and phosphatases by limited proteolysis. Given its suspected involvement at the cytoskeleton-membrane interface, calcium-mediated proteolysis is an example of a metabolic process which, if impaired, could provide a unifying basis for the slow progressive development of diverse structural and functional abnormalities within neurons. The multiplicity of mechanisms regulating its activity makes the CANP system a vulnerable target for disruption from various sources. A working hypothesis is advanced that down-regulation (inhibition) of neuronal calcium-mediated proteolysis in Alzheimer's disease is one critical and early step in the development of neurofibrillary degeneration and altered membrane cytoskeleton dynamics, which leads to membrane injury, accumulation of abnormal proteins, and synaptic dysfunction.
Examples of Additionally Constrained Multiple Linear Regression

Abstract An additionally constrained multiple linear regression technique is outlined for use with the prediction or specification of fields of geophysical variables. The additional constraints are the requirement that the predictions or specifications have spatial interrelationships which are similar to the dominant empirical orthogonal functions of the dependent variables. Since the traditional multiple linear regression estimates by definition minimize the mean square errors for the data used to develop the model, the utility of the additional constraint can be evaluated only when the regression models are tested on new data. A so-called jackknife technique is used in this regard. This additionally constrained multiple linear regression technique is tested on two examples of the specification of monthly values using independent data for the same month. The first is the specification of North Pacific sector 700-mb geopotential heights using the time coefficients of the first two empirical orthogonal fun...
COCORP: new perspectives on the deep crust

Summary. Relict sutures from colliding continents, regions characterized by a “young” Mono, layering and faulting throughout the crust, mid-crustal magma traps, and seismic “bright spots” which suggest deep crustal fluids are among recent COCORP findings. In addition, new studies of signal penetration, noise mitigation, recording geometry, and coherency filtering have yielded better understanding of, and substantial improvements in, data quality. Amplitude anomalies, or “bright spots”, in the Basin and Range may be due to magma at mid-crustal levels; in one case, a normal fault appears to link the deep magma with young surface volcanics. Another bright spot. 15 km deep in southeastern Georgia, has a flat geometry that suggests a gas/liquid interface, perhaps within fluids underthrust along an Appalachian suture. The Mono continues to appear relatively undisturbed in many regions of past deformation, suggesting that its formation post-dates these major tectonic episodes. The diversity of reflection patterns from the U.S. Cordillera casts further doubt on the generality of the common model of a reflective, layered lower crust underlying a transparent upper crust.
Practical Application of NASA-Langley Advanced Satellite Products to In-flight Icing Nowcasts

Experimental satellite-based icing products developed by the NASA Langley Research Center provide new tools to identify the locations of icing and its intensity. Since 1997, research forecasters at the National Center for Atmospheric Research (NCAR) have been helping to guide the NASA Glenn Research Center's Twin Otter aircraft into and out of clouds and precipitation for the purpose of characterizing in-flight icing conditions, including supercooled large drops, the accretions that result from such encounters and their effect on aircraft performance. Since the winter of 2003-04, the NASA Langley satellite products have been evaluated as part of this process, and are being considered as an input to NCAR s automated Current Icing Potential (CIP) products. This has already been accomplished for a relatively straightforward icing event, but many icing events have much more complex characteristics, providing additional challenges to all icing diagnosis tools. In this paper, four icing events with a variety of characteristics will be examined, with a focus on the NASA Langley satellite retrievals that were available in real time and their implications for icing nowcasting and potential applications in CIP.
Regulation of Dopamine Release from PC12 Pheochromocytoma Cell Cultures During Stimulation with Elevated Potassium or Carbachol

To examine the role of cyclic AMP in the process of catecholamine release experiments have been performed with cultures of PC12 pheochromocytoma cells. Elevated potassium (56 mM) and carbamylcholine (carbachol, 10(-4) M) cause rapid increases in cyclic AMP levels in the cultures that show a time course similar to that of evoked dopamine release. These secretogogue-induced increases in cyclic AMP levels are well correlated with release in terms of relative magnitude and calcium dependence. Forskolin (a direct activator of adenylate cyclase) causes dose-related increases in cyclic AMP levels in PC12 cell cultures that are synergistic with those caused by either elevated potassium or carbachol. At low concentrations forskolin significantly increases evoked release, whereas at higher concentrations it increases both spontaneous and evoked release. These results suggest that cyclic AMP may be involved in the process of dopamine release from PC12 cells in culture.
Allograft Use in Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) reconstruction is one of the most common procedures performed by orthopedic surgeons. While autograft reconstruction remains the gold standard, allograft tissues have become a controversial option for ACL reconstruction. No data currently exist regarding recent trends in graft choices, and no consensus exists over which graft type is most appropriate for which patient. In this article, we examine trends in ACL graft choice at our institution, and review the pertinent information a surgeon must consider when making this decision. We reviewed operating room records from 2002 to 2008 to determine trends in graft choice for primary single bundle ACL reconstruction. Total number of procedures performed, graft choices, and patient ages were recorded. Patients were divided into the following age groups: less than 16, 16 to 20, 21 to 30, 31 to 40, 41 to 50, and over 50. Percent of ACL reconstructions using allograft was calculated for each year, as well as for each age group. Data were analyzed for trends in ACL graft choice over this time period as well as for trends in graft choice by age. We hypothesized that the rate of allograft use in primary ACL reconstruction had increased over time and that allograft use was associated with higher patient age. We also review the risks, safety, and standards for tissue procurement. Allograft use increased significantly (p < 0.001) from 2002 (17%) to 2008 (46%). There was also a significant difference (p < 0.001) in average age of patients receiving allografts (40.4 years) and autografts (26.4 years). Allograft use was significantly associated with higher patient age (p < 0.05) and increased with each successive age group from a rate of 9.9% in patients under 16 to 79.9% in patients over 50. Our study found that allograft use in primary ACL reconstruction has significantly increased from 2002 to 2008 and is significantly more common in older patients.
Low-dimensional intrinsic material functions for nonlinear viscoelasticity

Rheological material functions are used to form our conceptual understanding of a material response. For a nonlinear rheological response, the possible deformation protocols and material measures span a high-dimensional space. Here, we use asymptotic expansions to outline low-dimensional measures for describing leading-order nonlinear responses in large amplitude oscillatory shear (LAOS). This amplitude-intrinsic regime is sometimes called medium amplitude oscillatory shear (MAOS). These intrinsic nonlinear material functions are only a function of oscillatory frequency, and not amplitude. Such measures have been suggested in the past, but here, we clarify what measures exist and give physically meaningful interpretations. Both shear strain control (LAOStrain) and shear stress control (LAOStress) protocols are considered, and nomenclature is introduced to encode the physical interpretations. We report the first experimental measurement of all four intrinsic shear nonlinearities of LAOStrain. For the polymeric hydrogel (polyvinyl alcohol - Borax) we observe typical integer power function asymptotics. The magnitudes and signs of the intrinsic nonlinear fingerprints are used to conceptually model the mechanical response and to infer molecular and microscale features of the material.
Prevention of experimental retinopathy of prematurity by vitamin A in the newborn rat model

UENPS.358 Prevention of experimental retinopathy of prematurity by vitamin A in the newborn rat model Xanthi Couroucli⁎, Yanhong Liang, Patricia Chevez-Barrios, Weiwu Jiang, Bhagavatula Moorthy Baylor College of Medicine, Houston, United States The Methodist Hospital, Houston, United States Background and aim Oxygen administration to preterm infants contributes to the development of bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP). We recently observed that all-trans retinoic acid (atRA), the active form of vitamin A (vit A), prevented the oxygen induced retinopathy in newborn rats. The purpose of this study was to test the hypothesis that exposure of newborn rats to vit A and hyperoxia would alleviate oxygen induced retinopathy compared to those exposed to hyperoxia alone. Materials and methods Newborn Fisher 344 rats were maintained in room air or exposed to hyperoxia (~95% O2) for 7 days. Some animals were treated i.p. with vit A either 10 mg/kg (3000 IU/kg) or 20 mg/kg (6000 IU/kg), once daily for the first 5 days of hyperoxia. Controls received corn oil and room air. Animals were sacrificed at selected time points after termination of hyperoxia. Vascular morphology was assessed in flat mounted retinas. The mRNA expression of VEGF and VEGFR-1/sFLT-1 and VEGFR-2 was determined by real time RT-PCR. Levels of atRA in the retinas were measured by Liquid Chromatography-Mass Spectrometry (LC-MS).
The effect of number of blades on the performance of H-Darrieus type wind turbine

Wind turbines are widely regarded as an alternative source for electrical power generation. Modern wind turbines are classified into horizontal axis wind turbine (HAWT) and vertical axis wind turbine (VAWT) categories. Vertical axis wind turbines (VAWTs) are attractive for applications in the built environment due to their ability to capture wind from different directions. One type of VAWTs is Darrieus turbine or H-type turbine. Experiments conducted in this paper aims to investigate the effect of number of blades in the performance of H-Darrieus type wind turbine. The experiments used 2, 3 and 4 blades to show rotation, torque and TSR (tip speed ratio) of wind turbine. A simulation using ANSYS 13.0 software will show the coefficient of power of wind turbine. The results of experiments showed that the number of blades rotation and torque influence the performance of wind turbine.
Partial absorption and “virtual” traps

The spatial probability distribution associated with diffusion and attenuation in partially absorbing media is studied. An equivalence is established between a system with free diffusion for x>0 and partial absorption for x 0) with a radiation boundary condition at x=0. By exploiting this equivalence, it is shown that the effect of a partially absorbing medium in the long-time limit is equivalent to that of a perfect, “virtual” trap whose size is smaller than the original absorbing medium. For short times, however, there is substantial penetration of diffusing particles into the absorber. The virtual trap approach is readily generalized to higher dimensions. This allows one to obtain the density profile of diffusing particles around a partially absorbing spherical trap. An unusual crossover between short-time penetration and long-time trapping occurs in two dimensions; the size of the virtual trap is exponentially small in the case of weak absorption, corresponding to an absorption time which is exponentially large.
Single-cell research: What determines its feasibility?

A general problem in single-cell research (SCR) is whether a representative cell is picked for analysis. In many cases, it may determine feasibility of SCR. Here, using a probability approach, we analyze this problem for laser tweezers Raman spectroscopy (LTRS), a promising technique for SCR. The results suggest that two main parameters determine the success and feasibility of SCR: the probability of picking a representative cell and the number of representative cells to be picked and analyzed. Both parameters determine the number of experiments required to obtain meaningful results. The approach is verified on several particular examples of SCR.
Exploring the energetics of histone H1.1 and H1.4 duplex DNA interactions

H1.1 and H1.4 bind tightly to both short DNA oligomers and to CT-DNA (Ka≈1×10(7)). Binding is accompanied by an unfavorable enthalpy change (∆H≈+22 kcal/mol) and a favorable entropy change (-T∆S≈-30 kcal/mol). The Tm for the H1.4/CT-DNA complex is increased by 9 °C over the Tm for the free DNA. H1.4 titrations of the DNA oligomers yield stoichiometries (H1/DNA) of 0.64, 0.96, 1.29, and 2.04 for 24, 36, 48, and 72-bp DNA oligomers. The stoichiometries are consistent with a binding site size of 37±1 bp. CT-DNA titration data are consistent with binding site sizes of 32 bp for H1.1 and 36 bp for H1.4. The heat capacity changes, ΔCp, for formation of the H1.1 and H1.4/CT-DNA complexes are -160 cal mol(-1) K(-1) and -192 cal mol(-1)K(-1) respectively. The large negative ΔCp values indicate the loss of water from the protein DNA interface in the complex.
Oxygen-radical absorbance capacity assay for antioxidants

Abstract A relatively simple but sensitive and reliable method of quantitating the oxygen-radical absorbing capacity (ORAC) of antioxidants in serum using a few μl is described. In this assay system, β-phycoerythrin (β-PE) is used as an indicator protein, 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) as a peroxyl radical generator, and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox, a water-soluble vitamin E analogue) as a control standard. Results are expressed as ORAC units, where 1 ORAC unit equals the net protection produced by 1 μM Trolox. The uniqueness of this assay is that total antioxidant capacity of a sample is estimated by taking the oxidation reaction to completion. At this point all of the nonprotein antioxidants (which include α-tocopherol, vitamin C, β-carotene, uric acid, and bilirubin) and most of the albumin in the sample are oxidized by the peroxyl radical. Results are quantified by measuring the protection produced by antioxidants. This solves many problems associated with kinetics or lag-time measurements. A linear correlation of ORAC value with concentration of serum, Trolox, vitamin C, uric acid, and bovine albumin is demonstrated. The coefficient of variation within a run is found to be about 2% and from run to run about 5%. Trolox, α-tocopherol, vitamin C, β-carotene, uric acid, and bilirubin completely protect β-PE from oxidation, while bovine albumin protects β-PE only partially. On a molar basis, the relative peroxyl radical absorbance capacity of Trolox, α-tocopherol acid succinate, uric acid, bilirubin, and vitamin C is 1:1:0.92:0.84:0.52. Bovine albumin per unit weight has a lower peroxyl absorbing capacity than these antioxidants. However, the serum protein fraction, containing some lipid-soluble antioxidants, represents the major contributor to the ORAC value found in whole serum. The minimum amount of vitamin C and uric acid which could still be detectable when added to a serum supernatant fractiion is 1.5 μg and 0.59 μg, respectively, which account for about 1% of the total ORAC value of the serum supernatant fraction.
The IR antenna pair coupled sensor element and its potential application in wavefront sensing

Abstract A single IR antenna-coupled square-law sensor does not preserve the phase of the radiation field. We considered an IR radiation detector element in which the square-law sensor is coupled with a pair of IR dipole antennas, the simplest coherently interconnected IR antenna array with the potential of preserving phase information. The circuit equivalent model is employed for analyzing the response features of an element to a tilted incident plane wave. The analytical results show that the response of such an element contains the phase difference information of incident radiation field at the positions of the two antennas and can be characterized by its induced phase shift, Δ , and the “visibility” of its oscillation profile, κ . In addition, the numerical computations for the case of shifted square-law detectors shows that Δ and κ are strongly affected by, and therefore can be controlled by the electric and geometrical parameters of the antenna element system. Furthermore, a method of using the response measurement of such elements to retrieve the wavefront phase information is also provided.
Large and small covers of a hyperbolic manifold

The exponent of convergence of a non-elementary discrete group of hyperbolic isometries measures the Hausdorff dimension of the conical limit set. In passing to a non-trivial regular cover the resulting limit sets are point-wise equal though the exponent of convergence of the cover uniformization may be strictly less than the exponent of convergence of the base. We show in this paper that, for closed hyperbolic surfaces, the previously established lower bound of one half on the exponent of convergence of “small” regular covers is sharp but is not attained. We also consider “large” (non-regular) covers. Here large and small are descriptive of the size of the exponent of convergence. We show that a Kleinian group that uniformizes a manifold homeomorphic to a surface fibering over a circle contains a Schottky subgroup whose exponent of convergence is arbitrarily close to two.
Existence of carcinine, a histamine-related compound, in mammalian tissues.

Abstract Carcinine (β-alanylhistamine) was synthesized in vitro from histamine and β-alanine. It was detected quantitatively using an HPLC method previously described for the quantification of the related compounds histamine, histidine, carnosine and 3-methylhistamine. Carcinine was identified in several tissues of the rat, guinea pig, mouse and human, and was then shown to be metabolically related in vivo to histamine, histidine, carnosine and 3-methylhistamine through radioisotopic labeling. The results demonstrate that carcinine may be concurrently quantitated using the same HPLC method as that used to measure histamine, histidine, carnosine and 3-methylhistamine. These findings suggest a role for carcinine in the carnosine-histidine-histamine metabolic pathway and in the mammalian physiologic response to stress.
Probing the Role of Metal Ions in the Catalysis of Helicobacter pylori 3-Deoxy-d-manno-octulosonate-8-phosphate Synthase Using a Transient Kinetic Analysis

3-Deoxy-d-manno-2-octulosonate-8-phosphate (KDO8P) synthase catalyzes the net condensation of phosphoenolpyruvate and d-arabinose 5-phosphate to form KDO8P and inorganic phosphate (Pi). Two classes of KDO8P synthases have been identified. The Class I KDO8P synthases (e.g. Escherchia coli KDO8P synthase) catalyze the condensation reaction in a metal-independent fashion, whereas the Class II enzymes (e.g. Aquifex aeolicus) require metal ions for catalysis. Helicobacter pylori (H. pylori) KDO8P synthase, a Zn2+-dependent metalloenzyme, has recently been found to be a Class II enzyme and has a high degree of clinical significance since it is an attractive molecular target for the design of novel antibiotic therapy. Although the presence of a divalent metal ion in Class II KDO8P synthases is essential for catalysis, there is a paucity of mechanistic information on the role of the metal ions and functional differences as compared with Class I enzymes. Using H. pylori KDO8P synthase as a prototypical Class II enzyme, a steady-state and transient kinetic approach was undertaken to understand the role of the metal ion in catalysis and define the kinetic reaction pathway. Metal reconstitution experiments examining the reaction kinetics using Zn2+, Cd2+, Cu2+, Co2+, Mn2+, and Ni2+ yielded surprising results in that the Cd2+ enzyme has the greatest activity. Unlike Class-I KDO8P synthases, the Class II metallo-KDO8P synthases containing Zn2+, Cd2+, Cu2+, and Co2+ show cooperativity. This study presents the first detailed kinetic characterization of a metal-dependent Class II KDO8P synthase and offers mechanistic insight for how the divalent metal ions modulate catalysis through effects on chemistry as well as quaternary protein structure.
To Stay or Not to Stay? That is the Question

In A Farewell to Arms, Hemingway said that childbirth was “a woman's battleground.” That statement is even more accurate today as women organize to make their voices heard in the offices of government and the boardrooms of insurance companies. How did the most joyous and fundamental of nature's events become the center of such heated controversy? When the British first settled in America, childbirth was the domain of female attendants in the home. It was not until the 1920s that delivery in the hospital became fashionable. The specter of puerperal fever, associated with maternity hospitals in the 19th century, had . . .
Evaluation of a Method to Quantify Glassy-Winged Sharpshooter (Hemiptera: Cicadellidae) Egg Maturation During a Feeding Assay

A method to improve an assay relating adult feeding to egg maturation by the glassy-winged sharpshooter (Hemiptera: Cicadellidae) was evaluated. The assay consisted on confining females to cowpea stems and quantifying feeding and egg maturation. Feeding was quantified by measuring excreta production. The number of eggs matured during the assay was estimated by taking the difference between female egg load (number of mature eggs carried by a female) at end of the assay (determined by dissection) and mean egg load of a subset of females dissected at start of the assay. Estimates of the number of mature eggs produced by females using the aforementioned approach improve as variability in egg loads of females entering the assay declines. As egg loads of females are variable, a pretreatment designed to reduce variance in egg loads of females entering the assay was evaluated. To accomplish this, females were divided into two groups. The control group was placed directly into the assay. The pretreatment group was given an oviposition period on sorghum before the assay. An oviposition period on sorghum was expected to reduce variance in egg load among females, as previous research found that sorghum was suitable for oviposition but provided poor nutrition for egg maturation. Dissection of a subset of females from each group before the assay determined that the mean and variance in egg load of females receiving the pretreatment was significantly reduced compared with females in the control group. Analysis of results from the feeding assay found that there was a significant relationship between feeding and egg maturation for females receiving the pretreatment, but not for females in the control group. Thus, reducing the mean and variance in egg load of females entering feeding assays resulted in detection of a significant positive relationship between feeding and egg maturation that otherwise would not have been observed.
1057 IDIOPATHIC RAPIDLY PROGRESSIVE GLOMERULONEPHRITIS WITH C3NeF AND HYPOCOMPLEMENTEMIA

Hypocomplementemia with circulating C3NeF occurs in membrano-proliferative glomerulonephritis and occasionally in acute post-streptococcal and lupus nephritis. A 7 year old boy with idiopathic rapidly progressive glomerulonephritis (IRPGN), with a serum C3 level of 16 mg/dl, a circulating 7S factor splitting C3 with the classical pathway blocked (C3NeF), and circulating IgG-containing complexes reactive with Clq, is reported. Crescents were present in 50% of the glomeruli. As in normocomplementemic IRPGN, ultrastructure showed subepithelial deposits located exclusively in that part of the basement membrane in apposition to the mesangium (capillary waist) and composed, by immunofluorescence, of C3, C5, and properdin. Following the initiation of therapy with corticosteroid, renal function greatly improved with concurrent fall in the levels of C3NeF and of Clq reactive complexes and rise in C3 concentration. At 8 months, 45% of glomeruli were globally sclerotic and IgG, C3, C5 and properdin could not be demonstrated. The observations emphasize that C3NeF can be present in many types of GN and that hypocomplementemia in RPGN is not necessarily indicative of a streptococcal origin.
A variable length fast Message Authentication Code for secure communication in smart grids

We propose a variable length Message Authentication Code (MAC) scheme for secure communication between Automated Metering Interface (AMI) devices and collector nodes in the smart grid. We prove the security of this scheme and analyze its performance with respect to three attributes namely: (i) communication overhead, (ii) verification delay and (iii) memory usage. The proposed scheme reduces the time for verification by at least two orders compared to existing hash based authentication protocols. The scheme thus provides an efficient solution to support high frequency exchange of large volume messages.
Electron mobilities in MOS channels formed along anisotropically dry etched [110] silicon trench sidewalls

Experimental silicon trench MOSFET structures were fabricated and used to estimate electron mobilities in MOS channels formed along [110] trench sidewalls. A channel electron mobility approaching 87% of its bulk value can be obtained. These results were derived from a novel trench fabrication process, measured MOSFET drain current-voltage characteristics and accurate two-dimensional device simulations of MOSFET transfer characteristics. >
Beyond the Measurement Trap A Reconstructed Conceptualization and Measurement of Woman Battering

Many areas of women's health, including battering, suffer from conceptual and methodological deficits. This article uses the "measurement trap" (Graham & Campbell, 1991), a set of conditions defined by lack of information resulting from a narrow conceptualization of the problem, poor existing data sources, inappropriate outcome indicators, and limited measurement techniques, as a framework for describing how current approaches to conceptualizing and measuring battering hamper research and program efforts in the field of domestic violence. We then describe an alternative conceptualization-and-measurement approach that is based on battered women's experiences. We argue that an experiential approach, which grounds measurement in women's lived experiences, improves our ability to conduct research that correctly identifies, monitors, and explains the epidemiology of this phenomenon and provides a solid basis for policy and program development.
Using protocol analysis to evaluate the usability of a commercial web site

Despite the increasing popularity of electronic commerce, there appears to be little evidence of the methodical evaluation of the usability of commercial web sites. The usability of a web site defines how well and how easily a visitor, without formal training, can interact with the site. This paper reports the results of a research project, which applies a systematic qualitative technique known as protocol analysis or think aloud method, to examine the usability of a commercial web site. About 15 usability principles and 3 evaluation parameters (content, navigation and interactivity) were used as a framework to analyze the verbal protocols of a sample of users interacting with a greeting card web site. The protocols provided evidence of usability problems caused by crowded content, poor navigation and cumbersome interactivity. These results underscore the importance of two crucial usability goals for commercial web sites: clear path to products and transparency of the ordering process.
Growth of Thermophilic and Hyperthermophilic Fe(III)-Reducing Microorganisms on a Ferruginous Smectite as the Sole Electron Acceptor

Recent studies have suggested that the structural Fe(III) within phyllosilicate minerals, including smectite and illite, is an important electron acceptor for Fe(III)-reducing microorganisms in sedimentary environments at moderate temperatures. The reduction of structural Fe(III) by thermophiles, however, has not previously been described. A wide range of thermophilic and hyperthermophilic Archaea and Bacteria from marine and freshwater environments that are known to reduce poorly crystalline Fe(III) oxides were tested for their ability to reduce structural (octahedrally coordinated) Fe(III) in smectite (SWa-1) as the sole electron acceptor. Two out of the 10 organisms tested, Geoglobus ahangari and Geothermobacterium ferrireducens, were not able to conserve energy to support growth by reduction of Fe(III) in SWa-1 despite the fact that both organisms were originally isolated with solid-phase Fe(III) as the electron acceptor. The other organisms tested were able to grow on SWa-1 and reduced 6.3 to 15.1% of the Fe(III). This is 20 to 50% less than the reported amounts of Fe(III) reduced in the same smectite (SWa-1) by mesophilic Fe(III) reducers. Two organisms, Geothermobacter ehrlichii and archaeal strain 140, produced copious amounts of an exopolysaccharide material, which may have played an active role in the dissolution of the structural iron in SWa-1 smectite. The reduction of structural Fe(III) in SWa-1 by archaeal strain 140 was studied in detail. Microbial Fe(III) reduction was accompanied by an increase in interlayer and octahedral charges and some incorporation of potassium and magnesium into the smectite structure. However, these changes in the major element chemistry of SWa-1 smectite did not result in the formation of an illite-like structure, as reported for a mesophilic Fe(III) reducer. These results suggest that thermophilic Fe(III)-reducing organisms differ in their ability to reduce and solubilize structural Fe(III) in SWa-1 smectite and that SWa-1 is not easily transformed to illite by these organisms.
The effects of reduced land fraction and solar forcing on the general circulation: results from the NCAR CCM

Jenkins, G.S., 1992. The effects of reduced land fraction and solar forcing on the general circulation: results from the NCAR CCM. Global Planet. Change, 7: 321-333. Land fraction and the solar energy at the top of the atmosphere (solar constant) may have been significantly lower early in Earth's history, it is likely that both of these factors played some important role in the climate of the early earth. The climate changes associated with a global ocean(i.e, no continents) and reduced solar constant are examined with a general circulation model and compared with the present-day climate simulation. The general circulation model used in the study is the NCAR CCM with a swamp ocean surface First, all land points are removed in the model and then the solar constant is reduced by 10% for this global ocean case. Results indicate that a 4 K increase in air temperature occurs with the global ocean simulation compared to the control. When solar constant is reduced by 10% under global ocean conditions a 23 K decrease in air temperature is noted. The global ocean warms much of the troposphere and stratosphere, while a reduction in the solar constant cools the troposphere and stratosphere. The largest cooling occurs near the surface with the lower solar constant. Global mean values of evaporation, water vapor amounts, absorbed solar radiation and the downward Iongwave radiation are increased under global ocean conditions, while all are reduced when the solar constant is lowered. The global ocean simulation produces sea ice only in the highest latitudes. A frozen planet does not occur when the solar constant is reducedmrather, the ice line settles near 30 ° of latitude, it is near this latitude that transient eddies transport large amounts of sensible hea! across the ice line acting as a negative feedback under lower solar constant conditions keeping sea ice from migrating to even lower latitudes. Clouds, under lower solar fl~rcing, also act as a negative feedback because they are reduced in higher latitudes with colder atmospheric temperatures allowing additional solar radiation to reach the surface. The overall effect of clouds in the global ocean is to act as a positive feedback because they are slightly reduced thereby allowing additional solar radiation to reach the surface and increase the warming caused by the removal of land. The relevance of the results to tile "Faint-Young Sun Paradox" indicates that reduced land fraction and solar forcing affect dynamics, heat transport, and clouds. Therefore the associated feedbacks should be taken into account in order to understand their roles in resolving the "Faint-Young Sun Paradox".
Signaling Mechanism of Poly(ADP-Ribose) Polymerase-1 (PARP-1) in Inflammatory Diseases

Poly(ADP-ribosyl)ation, attaching the ADP-ribose polymer chain to the receptor protein, is a unique posttranslational modification. Poly(ADP-ribose) polymerase-1 (PARP-1) is a well-characterized member of the PARP family. In this review, we provide a general update on molecular structure and structure-based activity of this enzyme. However, we mainly focus on the roles of PARP-1 in inflammatory diseases. Specifically, we discuss the signaling pathway context that PARP-1 is involved in to regulate the pathogenesis of inflammation. PARP-1 facilitates diverse inflammatory responses by promoting inflammation-relevant gene expression, such as cytokines, oxidation-reduction–related enzymes, and adhesion molecules. Excessive activation of PARP-1 induces mitochondria-associated cell death in injured tissues and constitutes another mechanism for exacerbating inflammation.
Effects of pressure and coal rank on carbon conversion in an entrained-coal gasifier

Abstract Elevated-pressure gasification tests were completed with North Dakota lignite, Wyoming subbituminous and Illinois No. 6 bituminous coals. Carbon conversion values obtained in these tests were compared with those obtained with the same three coals at atmospheric pressure. Increased pressure produced greater increases in carbon conversion as coal rank decreased.
Aspects of the mechanisms of smoke generation by burning materials

An investigation of smoke generation during the burning of natural and synthetic solid materials (relevant to fire safety problems), under simulated fire conditions, is presented. Smoke formation mechanisms, including flaming and nonflaming combustion, are reviewed, and the complex physical, chemical, and electrical processes, important in smoke particulate production, are identified. With reference to the smoke formation mechanisms, measured experimental data are discussed, and include effects of ventilation gas temperature, dependence on material composition, and chemical analysis of smoke particulates. Significant differences in smoke characteristics are observed between flaming and nonflaming conditions, which is attributed to specific differences in controlling mechanisms and resultant ways leading to particulate formation. The effects of polymer substrate properties and effects of additives for a given substrate on smoke properties are also discussed in terms of basic processes. It is shown that many of the measured trends can be interpreted by considering postulated mechanisms of particulate formation.
A newly identified surface coat on cochlear hair cells

Abstract Routine electron microscope methods do not well preserve or stain the surface coat or glycocalyx on cochlear hair cells. In other tissues, enhanced preservation and staining of these glycoconjugates was obtained following fixation with glutaraldehyde containing a cationic dye (e.g., Alcian blue and ruthenium red). When cochleas were fixed with glutaraldehyde containing Alcian blue, the endolymphatic surface of hair cells, but not the supporting cells, displayed an extensive (∼90 nm thick) surface coat. Alcian blue positive material was also observed in the tectorial and basilar membranes and in a portion of the spiral ligament. In addition, acellular bands of Alcian blue positive material were observed between the tectorial membrane and the reticular lamina or inner sulcus cells. Although the function of these cochlear glycoconjugates is not yet known, it is proposed that they serve to attach the tectorial membrane to the organ of Corti, and they are involved in stereocilia fusion following sound exposure and ototoxic drug administration.
THE ULTRASTRUCTURE OF GLENODINIOPSIS STEINII (DINOPHYCEAE).

The freshwater dinoflagellate Glenodiniopsis steinii Wolsoszynska was examined using computer-assisted three-dimensional reconstruction of serially sectioned cells observed with the transmission electron microscope and images from the scanning electron microscope. Vegetative cells contain ultrastructure typical of freshwater dinoflagellates including trichocysts, mitochondria, Golgi bodies, starch grains, and lipid bodies. The chloroplast is a single, multilobed structure, not multiple discoid chloroplasts as previously described. The "C" shape of the nucleus is apparently due in part to the size and location of the pusule.
Otogenic Pneumococcal Meningitis with Pneumocephalus

Streptococcus pneumoniae accounts for approximately 50% of bacterial meningitis cases in the United States annually. Since the advent of antibiotics, pneumococcal meningitis as a complication of a primary otogenic focus has been rare in the United States. The widespread use of immunosuppressants and increasing bacterial resistance to commonly prescribed antibiotics may contribute to a higher incidence of complications of otitis media in the future, similar to that of the pre-antibiotic era. We report a case of otogenic pneumococcal meningitis with pneumocephalus in an adult male on chronic immunosuppressant therapy. A 33-year-old man with Crohn's disease and azathioprine use presented to our Emergency Department with progressive headache while taking antibiotics for otitis media. Initial computed tomography scan of the brain revealed pneumocephaly, and cerebrospinal fluid analysis and culture diagnosed pneumococcal meningitis. The patient continued to have fevers while receiving intravenous antibiotics and underwent bilateral myringotomies; his clinical course subsequently improved significantly. Meningitis is a rare complication of Streptococcus pneumoniae infections since the advent of antibiotics; however, it may become more frequent with increasing antibiotic resistance and a growing population of immunocompromised patients. Additionally, pneumocephalus in the setting of meningitis and otitis media should raise the suspicion for mastoiditis (even without overt clinical findings) and early consultation with an otolaryngologist is warranted.
Herstatin, an Autoinhibitor of the Human Epidermal Growth Factor Receptor 2 Tyrosine Kinase, Modulates Epidermal Growth Factor Signaling Pathways Resulting in Growth Arrest

Herstatin is an autoinhibitor of the ErbB family consisting of subdomains I and II of the human epidermal growth factor receptor 2 (ErbB-2) extracellular domain and a novel C-terminal domain encoded by an intron. Herstatin binds to human epidermal growth factor receptor 2 and to the epidermal growth factor receptor (EGFR), blocking receptor oligomerization and tyrosine phosphorylation. In this study, we characterized several early steps in EGFR activation and investigated downstream signaling events induced by epidermal growth factor (EGF) and by transforming growth factor α (TGF-α) in NIH3T3 cell lines expressing EGFR with and without herstatin. Herstatin expression decreased EGF-induced EGFR tyrosine phosphorylation and delayed receptor down-regulation despite receptor occupancy by ligand with normal binding affinity. Akt stimulation by EGF and TGF-α, but not by fibroblast growth factor 2, was almost completely blocked in the presence of herstatin. Surprisingly, EGF and TGF-α induced full activation of MAPK in duration and intensity and stimulated association of the EGFR with Shc and Grb2. Although MAPK was fully stimulated, herstatin expression prevented TGF-α-induced DNA synthesis and EGF-induced proliferation. The herstatin-mediated uncoupling of MAPK from Akt activation was also observed in Chinese hamster ovary cells co-transfected with EGFR and herstatin. These findings show that herstatin expression alters EGF and TGF-α signaling profiles, culminating in inhibition of proliferation.
Influence of Interleukin-2 Deficiency on the Generation of Autoimmune B Cells

The production of auto-antibodies is one of the predominant characteristics of autoimmune disorders. Because IL-2 deficient mice develop autoimmunity, we asked how IL-2 deficiency might impair endogenous mechanisms of B cell tolerance. To this end, we mated BALB/c anti-dsDNA H chain knock-in mice, in which B cells producing anti-dsDNA antibodies are properly regulated, with IL-2 deficient mice and assessed the phenotype of their offspring. IL-2 deficient mice expressing the anti-dsDNA H chain knock-in allele developed anti-dsDNA antibodies of both IgM and IgG isotypes. Production of these antibodies occurred through the disruption of several mechanisms of endogenous tolerance, including deletion, maturational arrest, and follicular exclusion. In summary, our results suggest that IL-2 plays an important role in regulating B cell tolerance.
Response/ability: Imagining a critical race feminist paradigm for the creative arts therapies

Abstract This article examines the emergence of a critical race feminist paradigm and considers its relevance for the creative arts therapies. The diverse paradigms from which creative arts therapists articulate their practice are reviewed. The author's influences within feminist scholarship are presented as they relate to the practice of psychotherapy and to the creative arts therapies.
Treatment of proximal humeral chondrosarcoma with resection and allograft

Chondrosarcoma of the proximal humerus is an uncommon malignant bone tumor, and limited information is available about treatment. We retrospectively reviewed 31 patients treated by resection and replacement with allograft implants during the past 24 years. The patients were followed up for an average of more than 16 years. Despite some allograft complications, the overall success rate for the grafts was 77%, and patient survival was 96%. Only 1 patient died. Two patients required amputation for local recurrences, and the remainder did reasonably well despite some functional problems. On the basis of this study and by comparison data, we believe that proximal humeral chondrosarcomas are less malignant than chondrosarcomas in other sites. In comparing them against 26 metallic implants, we believe that resection and allograft implantation remains a generally successful treatment, although the improvement of the metallic devices over the years has made this technique more available and acceptable.
Correction of defective impressions by the selective addition of impression material.

R elining a deficient or otherwise defective impression after it has been completely relieved and vented is a commonly accepted procedure. Several studies have documented this technique and the resultant accuracy of the relined impressions.1-4 A similar technique is the widely used and accepted putty/wash impression system.i-6 However, the accuracy of correcting slightly defective or deficient impressions by venting, selectively adding a small amount of correcting impression material to the defective or deficient part, and reseating the impression has not been reported. If such a technique demonstrated consistently accurate results, the conservation of time and the economy of the use of minimal material would be beneficial to the dentist. This investigation was conducted to determine if acceptable results could be obtained with the use of a selective correction technique for slightly defective impressions.