cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaporitic paleosols in continental strata of the Carroza Formation, La Popa Basin, Mexico: Record of Paleogene climate and salt tectonics

A succession of continental red beds in the Paleogene Carroza Formation, northeastern Mexico, contains an assemblage of evaporite paleosols previously unknown in pre-Neogene strata that record the syndepositional exposure of nearby diapiric evaporite and a climatic shift to increasing aridity. Carroza red beds were deposited in an ephemeral braided-fluvial system in a high-accommodation setting. Paleosols developed in nearly all depositional settings, including channels, crevasse splays, and floodplains, and contain salic/natric, gypsic, baritic, and calcic horizons. Calcic paleosols are limited stratigraphically to the lowermost part of the formation in oyster-bearing estuarine strata and yield upsection to evaporitic paleosols, thus providing a record of increasingly arid conditions as the Paleogene marine shoreline shifted eastward, toward the Gulf of Mexico Basin. The increase in aridity reduced vegetation and residuum thickness on the exposed diapiric salt, consequently increasing the influx of evaporitic minerals into the basin, and driving the development of salic/natric, gypsic, and baritic horizons in all depositional environments. Evaporitic paleosols of the Carroza Formation have characteristics similar to soils forming today in climates with annual precipitation ranging from <80 mm/yr to as much as 450 mm/yr, in apparent conflict with estimates of subhumid to subtropical conditions from Carroza fossil leaf data. Because evaporitic paleosols are persistent throughout the Carroza section, we infer that a combination of spring-fed, high water tables, augmented by flood-basin inundation from high-discharge seasonal fluvial flood events sustained perennial woodlands, and sodium-caused clay dispersion created poor drainage in topographically low parts of a rapidly subsiding salt-withdrawal basin.
Effect of temperature on hydration kinetics and polymerization of tricalcium silicate in stirred suspensions of CaO-saturated solutions

Tricalcium silicate was hydrated at 274, 278, 283, 298, and 313 K in stirred suspensions of saturated CaO solutions under a nitrogen-gas atmosphere until the end of deceleratory period. The suspension conductivities and energy flows were measured continuously. The individual reaction rates for tricalcium silicate dissolution, calcium silicate hydrate precipitation, and calcium hydroxide precipitation were calculated from these measurements. The results suggest that the proportion of tricalcium silicate dissolved was determined by the rate of tricalcium silicate dissolution and the time to very rapid calcium hydroxide precipitation. The time to very rapid calcium hydroxide precipitation was more sensitive to changes in temperature than was the rate of tricalcium silicate dissolution, so that the proportion of tricalcium silicate hydration dissolved by the deceleratory period increased with decreasing temperature. The average chain length of the calcium silicate hydrate ascertained by magic-angle spinning nuclear magnetic resonance spectroscopy increased with increasing temperature.
Medical outcomes in preterm infants.

Many survivors of the newborn intensive care units who were premature do very well; some, however, go on to have a variety of medical complications related, in part, to their prematurity. An overview of the medical outcomes of prematurity are discussed in the areas of respiratory disease (bronchopulmonary dysplasia), gastrointestinal disorders (short gut syndrome and gastroensophageal reflux), growth and nutrition problems, vision, and hearing outcomes. These complications can be managed on a regular or vigilant outpatient basis and, if exacerbated, may require hospital management. Concepts to assist in family counseling on expected long-term medical outcomes of prematurity are discussed.
For Francisco Varela: explorer of the phenomenal world.

ABSTRACT Francisco Varela was an innovative thinker and researcher as well as a pioneer in the present dialog betweenscience and Buddhism. In this essay, I will first speak briefly about some of Francisco’s contributions to the worldat large and then relate a few vivid moments from my own interactions with him. the structure they called autopoiesis (selforganizing systems). The most radical aspectof autopoeisis is that neither environmentnor organism nor even the mind of theobserving scientist was to be objectified; allare seen as mutually self organizinginterdependent systems. Autopoiesis wasintended not only as philosophy of sciencein the phenomenological tradition, but as aframework and guide for research, asFrancisco himself proposed in his work onthe immune system.Francisco’s second effort was to establishfirst-person experience as a legitimatecontributor to science. One way of doingthis was to introduce phenomenology andencourage phenomenological discussion inother than entirely philosophical contexts.One such example was his editorship ofThe View from Within (a collection of paperson first-person phenomenology publishedas a special edition of the Journal ofConsciousness Studies) and his paper onHusserl’s treatment of time included inthat volume. Another strategy was to arguethat there was a centuries-old method oftraining the mind, Buddhist mindfulnessmeditation, which could render first personreports authoritative for science, especiallyscience conceived in a non-objectivistframework. In this strategy meditation istreated as the development of a skill,somewhat like learning to play the piano.Such a position is controversial, however,in the Buddhist traditions in whichmeditation is viewed not as gaining but as
Atlas-guided segmentation of brain images via optimizing neural networks

Automated segmentation of magnetic resonance (MR) brain imagery into anatomical regions is a complex task that appears to need contextual guidance in order to overcome problems associated with noise, missing data, and the overlap of features associated with different anatomical regions. In this work, the contextual information is provided in the form of an anatomical brain atlas. The atlas provides defaults that supplement the low-level MR image data and guide its segmentation. The matching of atlas to image data is represented by a set of deformable contours that seek compromise fits between expected model information and image data. The dynamics that deform the contours solves both a correspondence problem (which element of the deformable contour corresponds to which elements of the atlas and image data?) and a fitting problem (what is the optimal contour that corresponds to a compromise of atlas and image data while maintaining smoothness?). Some initial results on simple 2D contours are shown.
A New Concept for Aircraft Dynamic Stability Testing

A new approach to dynamic stability testing is introduced, based on the concept of orbital fixed-plane motion. An apparatus is conceived with which an aircraft model is forced in an orbital path while constrained to the fixed-plane reference system. An exposition of the concept is given and the potential advantages in captive model testing and applications in flight mechanics are indicated. Using a single apparatus, it is possible to 1) determine a complete set of first-order, dynamic stability derivatives, 2) vary the relationships between the associated motion parameters, and 3) simulate modes of aircraft motion. A validation scheme, which exploits the considerable flexibility of the method, facilitates the extension of dynamic data to actual flight conditions.
Quantitative Determination of Cannabinoid Receptor Antagonist Surinabant in Human Plasma by LC-UV and LC-ESI-MS/MS Methods

Abstract Surinabant [5-(4-bromophenyl)-1-(2,4-dichlorophenyl)-4-ethyl-N-(1-piperidinyl)-1H-pyrazole-3-carboxamide] is a cannabinoid receptor type 1 antagonist which is believed to indirectly inhibit the dopamine-mediated reward system for food, alcohol and nicotine addiction. Currently, there is no analytical method reported for the determination of surinabant in biological matrices. In this work, a liquid chromatographic (LC) method with both ultraviolet (UV) and electrospray ionization tandem mass spectrometric (ESI-MS/MS) detection has been developed and validated for the quantitative measurement of surinabant in human plasma to support the clinical investigation of this new drug. The compound AM251 was used for internal calibration. A protein precipitation procedure was employed for plasma sample preparation. Chromatographic separation of surinabant and internal standard was carried out on a Waters YMC™ Pro C4 cartridge column using a mobile phase containing 99.9% CH3CN/H2O (50:50, v/v) and 0.1% HCOOH...
Testing major evolutionary hypotheses about religion with a random sample.

Theories of religion that are supported with selected examples can be criticized for selection bias. This paper evaluates major evolutionary hypotheses about religion with a random sample of 35 religions drawn from a 16-volume encyclopedia of world religions. The results are supportive of the group-level adaptation hypothesis developed in Darwin’s Cathedral: Evolution, Religion, and the Nature of Society (Wilson 2002). Most religions in the sample have what Durkheim called secular utility. Their otherworldly elements can be largely understood as proximate mechanisms that motivate adaptive behaviors. Jainism, the religion in the sample that initially appeared most challenging to the group-level adaptation hypothesis, is highly supportive upon close examination. The results of the survey are preliminary and should be built upon by a multidisciplinary community as part of a field of evolutionary religious studies.
Pantographing self adaptive gap elements

This paper develops a so-called pantographing self adaptive gap element type contact strategy. Due to the manner of formulation, the scheme has the capability to handle large deformations in the contact zone; contact initiation in structure exhibiting either positive or indefinite stiffness characteristics; kinematic and material nonlinearity as well as; self adaptively adjusts load/time stepping. In this context, contact in pre and postbuckling structure can be treated. To illustrate the scheme, several benchmark problems are presented. These include contacting structure involving large deformation kinematics, inelastic behavior as well as pre and postbuckling stiffness characteristics.
Shaping Environmental Education Practices

Language has very real and powerful material outcomes for people and for the environments which they construct and inhabit. Social constructions of the category "environment" shape environmental education practices and ultimately affect strategies for mitigating environmental problems and degradation. Anthropologists can play a key role in clarifying these categories of meaning and their ramifications by examining what issues are considered, how they are considered, and what priorities are established, and by noting the things that are omitted, consciously or unconsciously, from the discussion.
Dimensions of Psychological Well-being Predict Consistent Condom Use among Older Adults Living with HIV

This study examined the role of psychological well-being in promoting consistent condom use among a sample of HIV-positive adults ages 50 and older living in New York City. Data were drawn from the Research on Older Adults with HIV (ROAH) project, and 328 sexually active participants (ages 50 to 78) were included in this cross-sectional analysis. Participants completed the Ryff Scales of Psychological Well-being (Ryff Journal of Personality and Social Psychology 57(6):1069–1081, 1989) and a detailed measure of sexual behavior in the past 90 days. Separate regression models were constructed by gender and sexual orientation (i.e., gay/bisexual men, straight men, and women). Psychological well-being was positively associated with sustained prevention practice, i.e. consistent condom use during every act of anal or vaginal sex. The effects of psychological well-being were observed over and above those associated with alcohol and drug use or disease severity (i.e. presence of an AIDS diagnosis). Unique dimensions of psychological well-being were associated with protected sex practice for each of the three gender/sexual orientation cohorts. This study is among the first to identify associations among specific psychological resources and consistent condom use among HIV-positive persons, and provides support for a salutogenic, eudaimonic approach to understanding and fostering prevention behavior among HIV-positive older adults.
Job turnover : a problem with employer-based health care

Many proposals for national health care, including that offered by the Commission on Comprehensive Health Care (the Pepper Commission), are based on pressing or requiring employers to purchase heal...
Aflatoxin deposition and clearance in the eggs of laying hens

Hens fed a diet containing 3310 μg of AFB1 and 1680 μg of AFB2 per kg feed for 28 days showed a significant decrease in egg production and egg weights by wk 3 and 4 of feeding, respectively. Transfer of aflatoxins to the eggs occurred rapidly, reaching maximum levels after 4–5 days, and remained relatively constant throughout aflatoxin feeding. The mean values for combined residue levels in eggs were less than 0.5 μg/kg. Levels of AFB2, AFM1 and AFM2 were similar in yolk and albumen while levels of B1 and B2a were higher in the yolk. Upon removal of the aflatoxin-containing diet, residues in eggs decreased rapidly. Clearance of aflatoxin residues from the albumen occurred faster than from the yolk. Thus, no residues were detected in the albumen and in the yolk after 5 and 7 days of withdrawal, respectively. No aflatoxin residues could be recovered from whole eggs after feeding the aflatoxin-free diet for 4 days.
Latino Adolescent Reproductive and Sexual Health Behaviors and Outcomes: Research Informed Guidance for Agency-Based Practitioners

Latinos are the largest and fastest growing minority youth group in the United States. Currently, Latino adolescents experience higher rates of teen pregnancy compared to any other racial or ethnic group and have disproportionately high levels of sexually transmitted infections and HIV. Latino teens are also affected by a number of social problems such as school dropout, poverty, depression and limited access to healthcare, which contributes to disparities in reproductive health outcomes for this population. Relatively few intervention research studies and programs have been dedicated to reducing sexual risk among Latino youth, despite their particular vulnerabilities in experiencing negative reproductive health outcomes. We provide recommendations for identifying the unique reproductive health needs of Latino youth and specific applied strategies so that agency-based social workers and other providers can develop family-based interventions that improve adolescent Latino sexual and reproductive health.
Alzheimer's disease untangled

The last year has seen major advances in the study of Alzheimer's disease (AD). Four mutations involving amino acid substitutions in exons 16 and 17 of the amyloid precursor protein (APP) gene, have been identified which co-segregate with the disease in some families multiply affected by early onset Alzheimer's disease. These mutations are strongly suggestive of a causative role for the amyloid precursor protein in Alzheimer's disease. Despite their rarity, these mutations are important because they represent the first known cause of Alzheimer's disease. Processing of APP must be central to the pathogenesis of the disease although the precise effects of these amino acid substitutions are not understood. Work is now being undertaken to characterise the processing pathways of APP and to identify other causes of AD. The development of models of AD using the APP mutations offers the possibility of identifying drug targets and developing more effective treatments than are presently available.
Glycogen in isolated mucosal and serosal fractions of turtle bladder.

Abstract 1. 1. The amount and behavior of glycogen in isolated fractions of turtle bladder were determined. The mucosal (epithelial) fraction contained approximately 30 % of whole bladder glycogen in both summer and winter. The remainder was contained in the serosal (muscle) fraction. 2. 2. The mucosal fraction made up a significantly greater proportion of total bladder wet weight in August than in January–March. 3. 3. Anoxia and 2,4-dinitrophenol caused rapid depletion of glycogen in both fractions. The substitution of choline for Na + in bathing fluids reduced glycogen losses both in the presence and absence of dinitrophenol. 4. 4. In each set of conditions tested, glycogenolysis was more extensive in the mucosal fraction than in the serosal fraction. 5. 5. Although the magnitudes of glycogen losses varied under different conditions, mucosal and serosal losses maintained an approximately constant relationship. It was suggested that glycogenolytic systems with similar characteristics (response patterns) but different intrinsic activities are operative in the two fractions.
Conventional 3D conformal versus intensity-modulated radiotherapy for the adjuvant treatment of gynecologic malignancies: a comparative dosimetric study of dose-volume histograms.

Abstract Objectives The goals of this study were to evaluate the feasibility of pelvic intensity-modulated radiotherapy (IMRT) in the adjuvant treatment of gynecologic malignancies and to compare the dose–volume histograms (DVHs) and determine the potential impact on acute and long-term toxicity based on the dose to target and nontarget tissues for both planning techniques. Methods Ten consecutive patients referred for adjuvant radiotherapy for gynecologic malignancies at the University of Pittsburgh School of Medicine and Magee–Womens Hospital were selected for CT-based treatment planning using the ADAC 3D version 4.2g and the NOMOS Corvus IMRT version 4.0. Normal tissues and critical structures were contoured on axial CT slices by both systems in conjunction with a gynecologic radiologist. These regions included internal, external, and common iliac nodal groups, rectum, upper 4 cm of vagina, bladder, and small bowel. Conventional treatment planning included 3D four-field box using 18-MV photons designed to treat a volume from the L 5 /S 1 border superiorly to the bottom of the ischial tuberosity on the AP/PA field and shaped blocks on the lateral fields to minimize the dose to the rectum and small bowel. A seven-field technique using 6-MV photons was used for IMRT. Restraints on small bowel for IMRT were set at 23.0 Gy ± 5% and 35.0 Gy± 5% for the rectum and 37.5 Gy ± 5% for the bladder while simultaneously delivering full dose (45.0 Gy) to the intrapelvic nodal groups in 1.8-Gy daily fractions. The dose–volume histograms where then compared for both treatment delivery systems. Results The volume of each organ of interest (small bowel, bladder, and rectum) receiving doses in excess of 30 Gy was compared in the 3D and IMRT treatment plans. The mean volume of small bowel receiving doses in excess of 30 Gy was reduced by 52% with IMRT compared with 3D. A similar advantage was noted for the rectum (66% reduction) and the bladder (36% reduction). The nodal regions at risk and the upper vagina all received the prescribed dose of 45.0 Gy. Conclusions Intensity-modulated radiotherapy appears to offer several advantages over conventional 3D radiotherapy (3D CRT) planning for adjuvant radiotherapy for gynecologic malignancies. These include a significant reduction in treatment volume for bladder, rectum, and small bowel. It is anticipated that this reduction in volume of normal tissue irradiated would translate into overall reduction in acute and potentially late treatment-related toxicity. Prospective trials are necessary to better evaluate the advantages in a larger group of patients.
The relation of sex and sense of direction to spatial orientation in an unfamiliar environment

An experiment is reported which tested the relation of sex (male, female) and self-reported sense of direction (good, poor) to spatial orientation ability, when walking or driving through an unfamiliar region of large-scale space. Three types of spatial orientation were tested: orientation to distant, non-visible landmarks surrounding the region; orientation to the starting point of a locomoted trajectory within the region; and orientation to compass directions. Sense of direction tended to be related to people's ability to maintain their orientation to distal landmarks, but in the walking task the relation was complex and varied as a function of sex. Sex was related to people's ability to orient to south, but neither sex nor sense of direction were related to people's ability to orient to the starting point of a locomoted trajectory. The findings are consistent with earlier reports that males are more likely than females to use cardinal directions for orientation, and they introduce the idea that the time course over which orientation to distal landmarks develops in an unfamiliar natural environment may differ for males and females as a function of self-reported sense of direction.
On the generalized critical region construct

In his paper "Implementation of a Generalized Critical Region Construct", Ford has proposed a modification to Brinch Hansen and Hoare's concept of Conditional Critical Regions. In this paper, we point out some of the problems with the original proposal and present many improvements in order to make the construct more useful.
Criterion adjustment and probability matching

Probability matching is contraindicated by the data of individual subjects (Dusoir, 1974) and by group data (Creelman & Donaldson, 1968); in general, response frequencies are not as extreme (i.e., distant from one-half) as the corresponding stimulus frequencies. This deviation from probability matching can be accounted for by at least two versions of an error-correcting model in which the subject’s decision criterion may shift only after an error, but not by a model which permits criterion shifts after correct responses. One version of the error-correcting model allows us to specify the dependence of response frequency on payoff magnitude and on signal strength. The deviation from matching is consistent also with a model that assumes that, on each trial, the criterion shifts in the direction of the sensory information, regardless of response accuracy. This model is thus applicable to situations in which trial-by-trial feedback is omitted.
Positive predictive value for polyps detected at screening CT colonography.

Purpose To determine the positive predictive value (PPV) for polyps detected at CT colonography (CTC).
Sex differences in opioid addiction careers.

Differences between the opioid addiction careers of 84 female and 91 male addicts were examined longitudinally. Data were collected from clients participating in methadone maintenance treatment pro...
Fatigue behavior of dissimilar spot friction welds in lap-shear and cross-tension specimens of aluminum and steel sheets

Fatigue behavior of dissimilar friction stir spot welds or spot friction welds in lap-shear and cross-tension specimens of aluminum 6000 series alloy and coated steel sheets is investigated based on experiments and three-dimensional finite element analyses. The Al/Fe spot friction welds in both types of specimens were tested under quasi-static and cyclic loading conditions. Optical micrographs of the welds after failure under quasi-static and cyclic loading conditions show that the Al/Fe welds in both types of specimens mainly fail along the interfacial surface between the aluminum and steel sheets. Three-dimensional finite element analyses based on the micrograph of the weld before testing were conducted to obtain stress intensity factor and J integral solutions for the crack fronts along the nugget circumferences of the welds in both types of specimens. The computational results suggest that the J integral and in-plane effective stress intensity factor solutions at the critical locations of the welds obtained from three-dimensional finite element analyses may be used as fracture mechanics parameters to correlate the experimental fatigue data for the Al/Fe spot friction welds in both types of specimens. Finally, the computational results are used to explain the experimental observations of the fatigue crack growth patterns of the welds.
A new property of the small-scale nonthermal motions in quiescent prominences

Small-scale nonthermal motions are a characteristic feature of astrophysical atmospheres, which have been studied on the basis of an interpretation of high-dispersion spectral line observations. The present paper is concerned with a study based on the close-lying lines Mg double-lambda 5173, 5167 and Fe(+) lambda 5169, in quiescent prominences. A summary of Mg b2, b4, and Fe(+) b3 prominence measurements and derived model profile parameters is presented in a table, while another table contains a summary of derived temperature and microvelocity parameter values. The most important result of the reported study is the finding that the Fe(+) b3 profiles in quiescent prominences are systematically narrower than one would expect from the Mg b2 profile widths and the assumption that both lines arise in regions of common T and v.
Developing and validating a stress appraisal measure for minority adolescents

Although there are a number of measures designed to assess the cognitive appraisal of stress in adult populations, currently there are no measures that are specifically designed to assess this important construct in adolescents. To overcome this limitation, the factorial validity and dimensionality of a dispositional measure of stress appraisal was examined in the current study. Using a multiethnic adolescent sample, both exploratory and confirmatory factor analyses resulted in a three-factor representation of appraisal. The three factors included two primary appraisal dimensions (Threat and Challenge) and one secondary appraisal dimension (Resources). This three-factor model, however, is inconsistent with four- and six-factor models found previously in adult samples. Thus, these findings suggest that the cognitive appraisals made by adolescents are less complex or differentiated than those of adults. Moreover, these findings suggest that dispositional measures are relevant for adolescent samples and should be incorporated into stress and coping paradigms.
The Gordian knot program: a short note on un-teaching "go to"

A simple device is presented for impressing students with the perils of unbridled "go to" statements. Whether or not one believes in go-to-less programming, it is clear to experienced programmers that unrestrained use of a go to statement leads to programs that are difficult to understand. This is much less clear to students in a beginning course, who see only very short programs. To impress these students that there is a problem, I frequently ask them to rewrite a "Gordian knot" program - one which is more than 50% go to statements - in the shortest possible form. A twenty-line program of this character is easy to construct, and gets the point across. Here is an example, which may be solved either under the assumption that only the very last value computed is needed, or that the final values of all variables (x, y, and z) are needed.
An Empirical Examination of Consumer Payment System Attribute Perceptions and Preferences: A Cross-Cultural Perspective

ABSTRACT Examination of the nature, scope, and richness of the payment system phenomena and buyer behavior in general would suggest some unique and important challenges for research. This study therefore attempts to explore payment system attribute perceptions and preferences of Asian-, Hispanic-, and Black-Americans. Strategic implications and future research directions are also suggested.
Industrial research enhancement program at the National Synchrotron Light Source

Abstract Industrial research has attracted more and more attention recently at synchrotron facilities. Bringing the state-of-the-art research capabilities provided by these facilities to the industrial user community will help this community to improve their products and processing methods, to foster competition and build the economy. The National Synchrotron Light Source (NSLS) has a long and celebrated history in research partnerships with industry since its inception more than 25 years ago, and both industry and the facility have benefited tremendously from these partnerships. Over the years, the ways in which industrial research is conducted at synchrotron facilities have evolved significantly, and a new paradigm of collaboration between industry and facilities is clearly needed to address this changing situation. In this presentation, the discussion will focus on an enhancement plan recently implemented at the NSLS to address industrial users' concerns and needs. The goal of NSLS Industrial Program Enhancement plan is to encourage greater use of synchrotron tools by industry researchers, improve access to NSLS beamlines by industrial researchers and facilitate research collaborations between industrial researchers and NSLS staff as well as researchers from university and government laboratories. Examples of recent developments in these areas will be presented.
IN VITRO INHIBITION OF COLLAGEN CROSS LINKS BY CATECHOL ANALOGS

Catechol analogs inhibit the formation of hydroxylysine-derived intermolecular collagen cross links in tissue cultures of chick embryo calvaria. Formation of intermolecular collagen cross links was measured following incorporation of [ 14 C]lysine, reduction with sodium borohydride, and elution from an ion exchange column with a pyridine-formate gradient. Cultures grown in the presence of 10 -3 M catechol, 10 -3 M dopamine, 10 -3 M L-dopa, or 10 -3 M D,L-serine-(2,3,4-trihydroxybenzyl)-hydrazide demonstrated between 43 and 84% inhibition of hydroxylysine formation. Collagen biosynthesis was not diminished in these cultures as compared to controls without additions or with β-aminopropionitrile when measured by collagenase digestion. The formation of hydroxylysine-derived intermolecular cross links was inhibited 34 to 93% for 5,5'-dihydroxylysinonorleucine and 7 to 71% for 5-hydroxylysinonorleucine. The catechol analogs also inhibit the activity of lysyl hydroxylase as measured by specific tritium release as tritiated water from an L-4,5- 3 H]lysine-labeled unhydroxylated collagen substrate prepared form chick calvaria. Since catechol analogs inhibit the formation of hydroxylysine in a cell-free assay, these compounds must pass into the cells of calvaria in this culture system to inhibit intracellular hydroxylysine formation and subsequently to diminish the reducible intermolecular cross links of the newly synthesized collagen.
Phase-tunable fluorophores based upon benzobis(imidazolium) salts.

A new series of highly photoluminescent benzobis(imidazolium) salts with tunable electronic and physical properties is described. Systematic structural manipulations provided a set of materials tha...
What auroral electron and ion beams tell us about magnetosphere-ionosphere coupling.

The electron and ion beams which have been detected on many rockets and satellites are of particular interest because beam particles carry information about both the ionosphere and the magnetosphere out to the distant tail. Stability analyses have shown that even the most dramatic beams have evolved until the particle distribution functions are only weakly unstable. The shortest plasma wave growth lengths in the auroral region are usually comparable to the size of an arc. The resulting clearest electron beams generally are relatively minor features of distribution functions which are dominated by plateaus, loss cones, broad or stretched out field aligned features, and hot or cold isotropic components. The true electron beams therefore represent a small fraction of the total electron number density. Ion beams carry a much larger fraction of all ions, but also are only weakly unstable. The electron beams seen at low altitudes can drive whistlers (both electromagnetic and electrostatic, including lower hybrid waves) and upper hybrid waves, which may be particularly intense near electron gyroharmonics. Ion beams can drive low frequency electromagnetic waves that are related to gyrofrequencies of several ion species as well as ion acoustic and electrostatic ion cyclotron waves. These latter waves can be driven both by the drift of ion beams relative to cold stationary ions and by the drift of electrons relative to either stationary or drifting ions. Abrupt changes or boundaries in the electron and ion velocity space distribution functions (e.g. beams and loss cones) have been analyzed to provide information about the plasma source, acceleration process, and regions of strong wave-particle interactions. Fluid analyses have shown that upgoing ion beams carry a great deal of momentum flux from the ionosphere. This aspect of ion beams is analyzed by treating the entire acceleration region as a black box, and determining the forces that must be applied to support the upgoing beams. This force could be provided by moderate energy (10's of eV) electrons which are heated near the lower border of the acceleration region. It is difficult to use standard particle detectors to measure the particles which carry electric current in much of the magnetosphere. Such measurements may be relatively easy within upgoing ion beams because there is some evidence that few of the hard-to-measure cold plasma particles are present. Therefore, ion beam regions may be good places to study fluid or MHD properties of magnetospheric plasmas, including the identification of current carriers, a study of current continuity, and some aspects of the substorm and particle energization processes. Finally, some of the experimental results which would be helpful in an analysis of several magnetospheric problems are summarized.
Fatigue crack propagation in Ti-6242 as a function of temperature and waveform

Abstract Constant amplitude continuous cycling tests were conducted on the near alpha titanium alloy Ti-6242 at room temperature and at 700 and 1000°F. The fatigue crack propagation rates at elevated temperature were in a scatterband around the room temperature data. The normal deterioration of the mechanical properties of Ti6242, as well as the associated embrittlement, is responsible for the increase of the fatigue crack propagation rates at 1000°F. The tests conducted in a vacuum environment at room temperature revealed a lower crack propagation rate than in the air environment. Rewelding was responsible for this phenomenon. Experiments involving a hold time at the highest temperature of 1000°F showed an apparent decrease of the FCP rates, in which creep mechanisms influence the behavior of the material.
Corporate brand reputation and brand crisis management

Purpose – This paper aims to provide insights into the what, why, and how of recognising corporate brand crisis through a synthesis of organisational experiences with threats to brand reputation, and to offer guidelines for analytic approaches and suggested organisational actions.Design/methodology/approach – The approach takes the form of a clinical set of examinations and interpretation of a substantial number of recognised corporate brand crisis situations. The analysis and suggested approaches in the paper have been tested with corporate executives and communications counselors in classrooms and private applied situations.Findings – The main points are: reputational trouble can come in many forms, from many sources and many publics; the most serious situations are those that affect the distinctive attribute/characteristic – “the essence of the brand” – most closely associated with the brand's meaning and success. A number of specific examples illustrate this point. However, past and present corporate ...
Water splitting: Catalyst or spectator?

The deposition of cobalt-phosphate onto photocatalytic haematite improves its ability to split water and thus create clean hydrogen fuel. The source of this improvement is, however, not yet understood, and now two separate studies suggest different roles for the deposited cobalt-phosphate.
Determination of caffeine content in coffee using Fourier transform infra-red spectroscopy in combination with attenuated total reflectance technique: a bioanalytical chemistry experiment for biochemists

In this report we describe an experiment to estimate the amount of caffeine present in common beverages with the use of Fourier transform infra-red spectroscopy (FTIR), using an attenuated total reflectance accessory as a sampling system. The absorbance band at 1655 cm−1 was used to estimate caffeine in standards and in the samples. The sensitivity of the technique was 5 ppm. The experiment provides a good demonstration of a bio-analytical technique that can be adopted either for a biochemistry or an analytical chemistry course.
SixthSense: Integrating information and the real world

Pattie Maes is an associate professor in MIT's Program in Media Arts and Sciences and associate head of the Program in Media Arts and Sciences. She founded and directs the Media Lab's Fluid Interfaces research group ‹http://fluid. media.mit.edu/› which develops technologies for seamless integration of the digital world and physical world. Previously, she founded and ran the Software Agents group ‹http://fluid.media.mit.edu/›. Prior to joining the Media Lab, Maes was a visiting professor and a research scientist at the MIT Artificial Intelligence Lab. She holds bachelor's and PhD degrees in computer science from the Vrije Universiteit Brussel in Belgium. Her areas of expertise are human-computer interaction and intelligent user interfaces. Maes is the editor of three books, and is an editorial board member and reviewer for numerous professional journals and conferences. She has received several awards: /Newsweek/ magazine named her one of the “100 Americans to watch for” in the year 2000; /TIME/ Digital selected her as a member of the Cyber-Elite, the top 50 technological pioneers of the hightech world; the World Economic Forum honored her with the title “Global Leader for Tomorrow”; Ars Electronica awarded her the 1995 World Wide Web category prize; and in 2000 she was recognized with the “Lifetime Achievement Award” by the Massachusetts Interactive Media Council.
Electronic structure contributions to electron-transfer reactivity in iron-sulfur active sites: 3. Kinetics of electron transfer.

The kinetics of electron transfer for rubredoxins are examined using density functional methods to determine the electronic structure characteristics that influence and allow for fast electron self-exchange in these electron-transport proteins. Potential energy surfaces for [FeX 4 ] 2 - , 1 - models confirm that the inner-sphere reorganization energy is inherently small for tetrathiolates (λ e s e i 0.1 eV), as evidenced by the only small changes in the equilibrium Fe-S bond distance during redox (Δr r e d o x 0.05 A). It is concluded that electronic relaxation and covalency in the reduced state allow for this small λ e s e i in this case relative to other redox couples, such as the tetrachloride. Using a large computational model to include the protein medium surrounding the [Fe(SCys) 4 ] 2 - , 1 - active site in Desulfovibrio vulgaris Rubredoxin, the electronic coupling matrix element for electron self-exchange is defined for direct active-site contact (H 0 D A ). The simple Beratan-Onuchic model is used to extend coupling over the complete surface of the protein to provide an understanding of probable electron-transfer pathways. Regions of similar coupling properties are grouped together to define a surface coupling map, which reveals that very efficient self-exchange occurs only within 4 u-bonds of the active site. Longer-range electron transfer cannot support the fast rates of electron self-exchange observed experimentally. Pathways directly through the two surface cysteinate ligands dominate k ∞ e s e , but surface-accessible amides hydrogen-bonded to the cysteinates also contribute significantly to the rate of electron self-exchange.
Combined use of biochemical indicators to assess sublethal pollution effects on the Gulf killifish ( Fundulus grandis )

Sublethal biochemical markers were used to identify liver enzyme induction in fish from a bayou in Pensacola, Florida. Gulf killifish,Fundulus grandis, from, a nonpolluted site were used in the study which included laboratory-induced fish and their various controls as well as the fish captured in the bayou. The biochemical markers tested were total content of cytochrome P-450, aryl hydrocarbon hydroxylase and ethoxyresorufin-O-deethylase activities, and the specific induction of the LM4bisozyme of the cytochrome P-450 system. The findings suggest that enzyme induction occurred at a sublethal level, indicating the presence of liver cytochrome P-450-inducing substances in the bayou.
Gut microbiota-produced succinate promotes C. difficile infection after antibiotic treatment or motility disturbance.

Clostridium difficile is a leading cause of antibiotic-associated diarrhea. The mechanisms underlying C. difficile expansion after microbiota disturbance are just emerging. We assessed the gene expression profile of C. difficile within the intestine of gnotobiotic mice to identify genes regulated in response to either dietary or microbiota compositional changes. In the presence of the gut symbiont Bacteroides thetaiotaomicron, C. difficile induces a pathway that metabolizes the microbiota fermentation end-product succinate to butyrate. The low concentration of succinate present in the microbiota of conventional mice is transiently elevated upon antibiotic treatment or chemically induced intestinal motility disturbance, and C. difficile exploits this succinate spike to expand in the perturbed intestine. A C. difficile mutant compromised in succinate utilization is at a competitive disadvantage during these perturbations. Understanding the metabolic mechanisms involved in microbiota-C. difficile interactions may help to identify approaches for the treatment and prevention of C. difficile-associated diseases.
A Palliative Ethic of Care: Clinical Wisdom at Life’s End

Correspondence: James Hallenbeck, M.D., Stanford University School of Medicine, VA Palo Alto Health Care System, 3801 Miranda Avenue, Palo Alto, California 94304, USA. Telephone: 650-366-4052; Fax: 650-849-0260; e-mail: james.hallenbeck@med.va.gov ©AlphaMed Press 1083-7159/2006/$20.00/0 A Palliative Ethic of Care: Clinical Wisdom at Life’s End By Joseph Fins, 281 pp., Jones and Bartlett Publishers, 2006. ISBN: 0763732923.
Magnetic resonance imaging in the evaluation of congestive cardiac failure

Congestive cardiac failure is the end-result of various cardiac disorders, and is a major contributor to morbidity, mortality, and financial burden throughout the world. Due to advances in the knowledge of the disease and scanner technology, magnetic resonance imaging (MRI) is playing an increasingly important role in the evaluation of cardiac failure, including in establishing diagnosis, problem solving, risk stratification, and monitoring of therapy. This review discusses and illustrates the role of MRI in the assessment of congestive cardiac failure.
Management of pregnancy after stillbirth

It is difficult for clinicians to counsel, evaluate, and manage subsequent pregnancies after stillbirth as little is known about pregnancy outcome after a stillbirth. In a significant number of cases, either the evaluation was incomplete or the prior stillbirth remains unexplained despite a complete work-up. In addition, there are important psychological and emotional issues when dealing with a pregnancy resulting in a stillbirth. The overall recurrence risk for stillbirth is increased 2 to 10 folds in the next pregnancy, depending on the circumstances. Understanding the circumstances of the previous stillbirth is important for counseling about stillbirth recurrence risk. Categorization of the cause of the previous stillbirth will allow better estimation of individual recurrence risk of the condition that is associated with stillbirth and help guide management.
Validity and reliability of the abdominal test and evaluation systems tool (ABTEST) to accurately measure abdominal force.

Abstract Objectives Ability to generate force from the core musculature is a critical factor for sports and general activities with insufficiencies predisposing individuals to injury. This study evaluated isometric force production as a valid and reliable method of assessing abdominal force using the abdominal test and evaluation systems tool (ABTEST). Secondary analysis estimated 1-repetition maximum on commercially available abdominal machine compared to maximum force and average power on ABTEST system. Design This study utilized test–retest reliability and comparative analysis for validity. Reliability was measured using test–retest design on ABTEST. Validity was measured via comparison to estimated 1-repetition maximum on a commercially available abdominal device. Methods Participants applied isometric, abdominal force against a transducer and muscular activation was evaluated measuring normalized electromyographic activity at the rectus-abdominus, rectus-femoris, and erector-spinae. Results Test, re-test force production on ABTEST was significantly correlated (r = 0.84; p Conclusions Data indicate the ABTEST can accurately measure rectus-abdominus force isolated from hip-flexor involvement. Negligible activation of erector-spinae substantiates little subjective effort among participants in the lower back. Results suggest ABTEST is a valid and reliable method of evaluating abdominal force.
Transcription and replication of a natural hepatitis B virus nucleocapsid promoter variant is regulated in vivo by peroxisome proliferators.

Abstract A hepatitis B virus (HBV) transgenic mouse containing a naturally occurring mutation in the nucleocapsid promoter (A1764T plus G1766A) that inhibits the retinoid X receptor α (RXRα) plus peroxisome proliferator-activated receptor α (PPARα) heterodimer from binding to the proximal nuclear hormone receptor recognition sequence has been generated. Viral transcription and replication occur in the liver and kidney. The nucleocapsid promoter mutation does not prevent peroxisome proliferators from increasing viral transcription and replication in the liver of these variant HBV transgenic mice. This suggests that peroxisome proliferators may enhance viral transcription directly in a PPARα-dependent manner through the nuclear hormone receptor recognition site in the enhancer 1 region of the HBV genome. Hepatocyte nuclear factor 4 (HNF4) binding to the proximal nuclear hormone receptor recognition sequence in the nucleocapsid promoter appears to limit RNA synthesis from the precore transcription initiation site. Consequently, the variant HBV transgenic mice transcribe very little precore RNA and secrete extremely low levels of hepatitis B e antigen (HBeAg) compared with the wild-type HBV transgenic mice. This is consistent with the suggestion that viruses expressing HBeAg are preferentially eliminated in infected individuals when they seroconvert from HBeAg positive to anti-HBe antibody-positive status, leaving escape HBV variants that have reduced HBeAg expression.
Angiosarcoma of the humerus presenting with fluid-fluid levels on MRI: a unique imaging presentation.

Fluid–fluid levels are a known feature of a number of osseous lesions, but have never before been described in primary osseous angiosarcoma, which is itself a rare malignancy. We report a case of humeral angiosarcoma presenting with fluid–fluid levels. Recognizing this entity as a possible etiology for fluid–fluid levels could help radiologists to avoid potential confusion in the differential diagnosis on imaging.