cssi/SciSciGPT-SciSciNet huggingface dataset:
Mixing Behavior of Colyophilized Binary Systems

The purpose of this study was to investigate the factors which govern the mixing of amorphous sucrose with trehalose, poly-(vinylpyrrolidone) (PVP), dextran, and poly(vinylpyrrolidone-co-vinyl acetate) (PVP/VA). These materials were chosen as model systems to represent multicomponent freeze-dried pharmaceutical preparations. Mixtures were prepared by colyophilization of the components from aqueous solutions. The glass transition temperatures (Tg) of these mixtures were measured using differential scanning calorimetry (DSC) and were compared to predictions based on simple mixing rules. FT- Raman spectroscopy was used to probe selected mixtures for evidence of molecular interactions between components. Colyophilized mixtures were confirmed to be amorphous by X-ray powder diffraction. The Tg values of the various mixtures generally were lower than values predicted from free volume and thermodynamic models, indicating that mixing is not ideal. The FT-Raman spectra of colyophilized sucrose-PVP and sucrose-PVP/VA mixtures provided evidence for interaction between the components through hydrogen bonding. Hydrogen bonds formed between components in colyophilized sucrose-additive mixtures are formed at the expense of hydrogen bonds within sucrose and in some cases within the additive. A thermodynamic analysis of these mixtures indicates that mixing is endothermic, which is consistent with a net loss in the degree of hydrogen bonding on mixing. There is also a positive excess entropy of mixing which accompanies the net loss in hydrogen bonds. Despite this gain in excess entropy, the excess free energy of mixing is positive, consistent with the observed deviations in Tg from values predicted using models which assume ideal mixing.
Symmetric solutions to the maximally Gauss-Bonnet extended Einstein equations

The most general gravitational lagrangian which can be constructed from the curvature two-form, the vielbein one-form, and tensors invariant in the tangent space is a linear combination of dimensionally extended Euler characteristics. Several recent studies indicate that superstring lagrangians include such terms. In an arbitrary number of dimensions, with arbitrary torsion, we show that in the most general such extended theory the only static, spherically symmetric, massive solutions to the variational equations of motion contain gravitational singularities. The existence of an event horizon is proved for certain cases, and a bound on the location of singularities is found. A certain class of non-asymptotically flat solutions is found for which the metric and the torsion are not entirely determined by the field equations.
Gonadotropin-releasing hormone receptor binding in bovine anterior pituitary

Abstract Synthetic gonadotropin-releasing hormone (GnRH) was monoiodinated at a high specific radioactivity with 125 I. The iodinated hormone retained full biological activity as assessed by the release of luteinizing hormone in vitro form bovine anterior pituitary tissue slices. Specific binding of 125 I-labeled gonadotropin-releasing hormone of high affinity and low capacity was obtained using dispersed bovine anterior pituitary cells. The binding had sigmoid characteristics, compatible with the presence of more than one binding site. The subcellular fraction responsible for binding was identified with the plasma membranes. However, significant binding also occurred in the secretory granules fraction. The plasma membranes were solubilized with sodium dodecyl sulfate. Using gonadotropin-releasing hormone covalently to a solid phase, a protein was purified by an affinity technique from the solubilized plasma membrane preparation which possessed similar binding properties as plasma membranes, both intact and solubilized. The protein migrated as a single component on polycrylamide gel in sodium dodecyl sulfate and the estimated molecular weight was 60 000. The character of the gonadotropin-releasing hormone concentration dependence binding as well as association kinetics were multiphasic and suggested the presence of more than one binding site. When analyzed by the Hill plot, the Hill coefficient of all binding curves was always greater than one which is compatible with positive cooperativity. This was further supported by the dissociation studies where the dissociation rate was inversely proportionate to both the gonadotrophin-releasing hormone concentration and the time interval during which the gonadotropin-releasing hormone-gonadotropin-releasing hormone receptor protein complex was formed. Using difference chromatography, aggregation of the purified gonadotropin-releasing hormone receptor protein was demonstrated to occur upon its exposure to gonadotropin-releasing hormone. The formed macromolecular complexes bound preferentially 125 I-labeled gonadotropin-releasing hormone. It is concluded that a single receptor protein is responsible for gonadotropin-releasing hormone binding in the bovine anterior pituitary. It is a part of the plasma membranes. Its interaction with gonadotropin-releasing hormone provokes transitions of the protein into different allosteric forms and this may be related to the biological effect of gonadotropin-releaing hormone on gonadotropin secretion.
On Deciding Readiness and Failure Equivalences for Processes

In this paper, we study the complexity of deciding readiness and failure equivalences for finite state processes and recursively defined processes specified by normed context-free grammars (CFGs) in Greibach normal form (GNF). The results are as follows: (1) Readiness and failure equivalences for processes specified by normed GNF CFGs are both undecidable. For this class of processes, the regularity problem with respect to failure or readiness equivalence is also undecidable. Moreover, all these undecidability results hold even for locally unary processes. In the unary case, these problems become decidable. In fact, they are ?p2-complete, We also show that with respect to bisimulation equivalence, the regularity for processes specified by normed GNF CFGs is NL-complete. (2) Readiness and failure equivalences for finite state processes are PSPACE-complete. This holds even for locally unary finite state processes. These two equivalences are co-NP-complete for unary finite state processes. Further, for acyclic finite state processes, readiness and failure equivalences are co-NP-complete and they are NL-complete in the unary case. (3) For finite tree processes, we show that finite trace, readiness, and failure equivalences are all L-complete. Further, the results remain true for the unary case. Our results provide a complete characterization of the computational complexity of deciding readiness and failure equivalences for several important classes of processes.
The contribution of morphology to word recognition

Evidence of morphological processing was investigated in three word recognition tasks. In the first study, phonological ambiguity of the base morpheme in morphologically complex words of Serbo-Croatian was exploited in order to evaluate the claim that the base morpheme serves as the unit by which entries in the lexicon are accessed. An interaction of base morpheme ambiguity and affix characteristics was obtained and this outcome was interpreted as evidence that all morphological constituents of a word participate in lexical access. In the second study, facilitation due to morphological relatedness of prime and target was observed with Serbo-Croatian materials in the lexical decision and naming versions of the repetition priming task and results were interpreted as evidence of a morphological principle of organization among wholeword forms in the lexicon. In the third study, morphological affixes of both English and Serbo-Croatian words were segmented from a source word and affixed to a target word more rapidly than phonemically matched controls. Results suggest that the morphological constituents of complex words are available in some word recognition tasks and that morphological knowledge is represented in the speaker's lexicon.
Effect of Heat Treatment at 1150°C on Creep-Rupture Properties of a Fe3Al-Based Alloy

The effects of heat treatment at 1,150 C on the creep-rupture properties of a Fe{sub 3}Al-based alloy were studied. Tests were conducted in air using various test temperatures and stresses. By plotting the data to a power-law equation, the activation energy for creep was determined to be approximately 150 kcal/mole and the creep exponent to be about 8. Optical metallography and scanning electron microscopy of ruptured specimens indicated that failure was in a ductile manner by microvoid coalescence at grain boundaries and triple points. Analytical electron microscopy was used to study characteristics of the microstructure and to identify Zr-rich precipitates that formed during heat treatment or creep testing. These precipitates were found to provide strengthening by pinning dislocations and grain boundaries.
Electrophysiological properties of frog spinal dorsal horn neurons and their responses to serotonin: an intracellular study in the isolated hemisected spinal cord.

Abstract Frog dorsal horn neurons and their responses to serotonin (5-HT) were studied in intracellular recordings from isolated hemisected spinal cords. Electrophysiological properties were comparable to those of mammals. Bath application of 5-HT (10–50 μM) increased the excitability and caused membrane depolarizations in 7/14 cells, reduced or abolished activity and caused hyperpolarizations in 4 neurons, exerted a biphasic effect in two cells, and produced no detectable change in one neuron. The multiple effects of 5-HT may be mediated through different 5-HT receptor subtypes.
All the News that’s Fat to Print: The American “Obesity Epidemic” and the Media

In the last twenty years scientific, medical, and public health interest in obesity has skyrocketed. Increasingly the term “epidemic” is being used in the media, medical journals, and public health policy literature to describe the current prevalence of fatness in the U.S. Using social scientific literature on epidemics, social problems, and feminist theories of the body, this paper traces the historical emergence of the “obesity epidemic” through an analysis of 751 articles on obesity published in The New York Times between 1990 and 2001. Through the identification and analysis of three discursive pairings I argue that the “obesity epidemic” is a part of a new breed of what I call “post-modern epidemics,” epidemics in which unevenly medicalized phenomena lacking a clear pathological basis get cast in the language and moral panic of “traditional” epidemics. I show how this moral panic together with the location of the problem within the individual precludes a more macro level approach to health and health care delivery at a time when health care services are being dismantled or severely cut back.
Effects of Thyroid-Stimulating Hormone on Human Thyroid Carcinoma and Adjacent Normal Tissue*

Effects of TSH on the adenylate cyclase-cAMP system and some parameters of intermediary metabolism were investigated in human thyroid carcinoma and adjacent normal thyroid tissue. Basal adenylate cyclase activity and cAMP concentrations were significantly higher in carcinomatous tissue. Basal [1-l4C]glucose oxidation, 32Pi incorporation into phospholipids, and organification of iodide were similar in both tissues. Stimulation of cAMP by TSH was significantly greater in normal compared to carcinomatous tissue. In neither tissue was there a good correlation between TSH stimulation of adenylate cyclase activity and cAMP concentrations. The TSH stimulation of 32Pi incorporation into phospholipids by TSH was significantly greater in normal tissue. The mean effect of TSH on iodide organification and glucose oxidation was similar in normal and carcinomatous tissue. Although specific binding of TSH was demonstrated in both normal and carcinomatous tissue, it did not correlate very well with stimulation of adenyla...
The contribution of formal planning to decisions

This paper presents results from a study of the contribution of formal strategic planning to 1087 decisions made by 129 of the Fortune 500 companies during the years 1982–86. Multivariate analysis of covariance revealed that the characteristics of decisions account for over 15 percent of the variance in data and should therefore be regarded as important determinants of the contribution planning makes to decision-making. The planning systems studied contributed more to decisions that were considered important and risky, and also to those that were either global in nature or related to divestments.
Ritual versus logic in significance testing in communication research

Statistical tests of significance tend to produce Type I error probabilities far in excess of the reported “alphas”; when more than one significance test is conducted on a data set. Since this condition is almost always the case in communication research, most reported alpha levels are little more than fiction as they relate to the occurrence of the Type I errors they are supposed to index and monitor. The calculation of an alpha percentage (α%) allows an estimation of the number of Type I errors being reported as “significant,”; suggests a rational basis for where to set the nominal alpha level for a given data set in order to obtain any specified ratio of fictional to “real”; results, and provides a general method of controlling Type I error rates since it is applicable across all tests of significance.
A two-spark schlieren system for very-high velocity measurement

To produce movies of supersonic flows, from which meaningful information can be extracted, is a non-trivial task. In a supersonic wind tunnel, speeds are of the order of 1,000 m/s and the scale of turbulent structures is typically of the order of millimeter. To capture the flow details, exposure times of less than 0.1 µs, and framing rates from 1 to 100 µs are desirable. While high-speed movie cameras with framing rates up to 5 million per second are commercially available, they are expensive, require an extremely-powerful light source, and are inflexible as to adjusting the exposure and the framing rate independently.
Comparison of Visual and Spectrophotometric Methods of Broth Microdilution MIC End Point Determination and Evaluation of a Sterol Quantitation Method for In Vitro Susceptibility Testing of Fluconazole and Itraconazole against Trailing and Nontrailing Candida Isolates

Visual determination of MIC end points for azole antifungal agents can be complicated by the trailing growth phenomenon. To determine the incidence of trailing growth, we performed testing of in vitro susceptibility to fluconazole and itraconazole using the National Committee for Clinical Laboratory Standards broth microdilution M27-A reference procedure and 944 bloodstream isolates of seven Candida spp., obtained through active population-based surveillance between 1998 and 2000. Of 429 C. albicans isolates, 78 (18.2%) showed trailing growth at 48 h in tests with fluconazole, and 70 (16.3%) showed trailing in tests with itraconazole. Of 118 C. tropicalis isolates, 70 (59.3%) showed trailing growth in tests with fluconazole, and 35 (29.7%) showed trailing in tests with itraconazole. Trailing growth was not observed with any of the other five Candida spp. tested (C. dubliniensis, C. glabrata, C. krusei, C. lusitaniae, and C. parapsilosis). To confirm whether or not isolates that showed trailing growth in fluconazole and/or itraconazole were resistant in vitro to these agents, all isolates that showed trailing growth were retested by the sterol quantitation method, which measures cellular ergosterol content rather than growth inhibition after exposure to azoles. By this method, none of the trailing isolates was resistant in vitro to fluconazole or itraconazole. For both agents, a 24-h visual end point or a spectrophotometric end point of 50% reduction in growth relative to the growth control after 24 or 48 h of incubation correlated most closely with the result of sterol quantitation. Our results indicate that MIC results determined by either of these end point rules may be more predictive of in vivo outcome for isolates that give unclear visual end points at 48 h due to trailing growth.
Propagation of a brittle crack at constant and accelerating speeds

Abstract The integral solutions for a symmetrical crack propagating at a varying speed in an elastic solid under the action of an arbitrary symmetrical crack pressure are obtained as sums of associated static solutions and stress-wave integrals. Two special cases are studied in detail. For the case of a symmetrical crack running at a constant speed under a uniform pressure, exact dynamic solutions for crack shape and stress distribution with singularities in the crack plane are obtained in closed forms that are easily comparable to associated static solutions. The difference between dynamic and static solutions for quantities such as crack shape and stress intensity factors is governed by dynamic correction factors which are nondimensional functions of Poisson's ratio and the ratio between crack speed and shear-wave speed. The values of these dynamic factors are obtained for large range of crack speed and the difference can clearly be determined from the results obtained. A study is made for the propagation of a crack at a constant acceleration. The quantities similar to those obtained for the above constant-speed crack are also obtained. The deviations of crack-shape and stress-intensity factors from the associated static state are relatively smaller for an accelerating crack than for a constant-speed crack propagating at the same speed.
High concentrations of chlorine monoxide at low altitudes in the Antarctic spring stratosphere: secular variation

We have reported the observation of millimetre-wave emission from abnormally high concentrations of chlorine monoxide, ClO, in the lower stratosphere over McMurdo Station, Antarctica during the period 1–22 September 1986 and demonstrated1 its diurnal behaviour. Here we report on the secular variation of daytime ClO in the lower stratosphere with a time resolution of 4 or 5 days, during the period 1 September to 16 October. We show that the ClO concentration declines during the latter half of September and disappears by early October. As ClO is directly involved in a catalytic ozone destruction cycle, these observations give evidence that the Antarctic ozone hole2 is caused by a chemical depletion mechanism which operates in the early spring. This is also consistent with models in which large quantities of ClO are maintained through chemical reactions3–5 on the surface of polar stratospheric cloud particles which evaporate with the warming of the stratosphere.
Early Modern Postmodern Polities: The Narratives of Colonial Political Development. A Review of: The Varieties of Political Experience in Eighteenth-Century America

Richard R. Beeman's The Varieties of Political Experience in Eighteenth-Century America is an ambitious effort to re-think the development of democratic political practices during the eighteenth century. Beeman orients his narrative around the trope of pluralism. Pluralism, for Beeman, works on two levels. First, he argues that one cannot tell a common story of colonial political practices during the eighteenth century. In fact, he writes, "diversity may be the only generalization that we can make about eighteenth-century American political culture" (pp. 1-2). Second, Beeman argues that ethnic, religious, economic, and political diversity was vital to moving American politics in a democratic direction, first in the western backcountry and the cities and then-during and after the American Revolution-throughout the new nation.
Application of one-dimensional mechanical formulations to model the sagging behavior of a polymer sheet

The deformation of a heated plastic sheet clamped on two opposite sides subject to sagging under its own weight was examined experimentally and then modeled using two separate one-dimensional approaches based upon cable (membrane) and beam formulations. The cable formulation neglects both bending and shear deformation, but includes a generalized Maxwell viscoelastic constitutive model to capture the time-dependent nature of sheet sag. The resulting equations are integrated using a Runge-Kutta technique and solved via a shooting method. The beam formulation is based upon the Timoshenko theory and thus includes shear deformation along with the flexural contributions. A finite element method is developed from application of the principle of virtual work for the beam written in curvilinear coordinates in order to include the effects of finite deformation. A generalized Maxwell model is again employed to account for the time-dependent material response. In both formulations, the method of reduced variables is used to describe the variation of material response with temperature. The effect of temperature and thermal relaxation is included. The particular case of a styrenic material is discussed in detail.
Rhetorical Action in Professional Space Information Architecture as Critical Practice

This article focuses on information architecture as a site for developing critical practice for technical communication. Such a focus suggests methods for rhetorical intervention aimed at democratizing the process of technocultural development. As a site of intervention, information architecture invites practitioners and academics to develop plans for action based on the analysis generated in descriptive research, completing the circuit from analysis to informed action.
EFFECT OF SWITCHING METHANE/OXYGEN REACTANTS IN A COAXIAL INJECTOR ON THE STABILITY OF NON-PREMIXED FLAMES

An investigation was performed to examine the effect of switching non-premixed gaseous fuel and oxidizer coaxial injector flow configurations on the stability of a CH4/O2 diffusion flame. Over 170 ...
Incorporating nonmarket time into benefit-cost analyses of social programs: An application to the self-sufficiency project ☆

Abstract Benefit–cost analysis is used extensively in the evaluation of social programs. Often, the success or failure of these programs is judged on the basis of whether the calculated net benefits to society are positive or negative. Almost all existing benefit–cost studies of social programs count entire increases in income accruing to participants in a social program as net benefits to society. However, economic theory implies that the conceptually appropriate measure of the impact of a government program on any group of individuals is the net change in their surplus (or economic rent), rather than the net change in their income. For example, if a social program causes increases in income by increasing work hours, then the lost nonmarket time that accompanies these increases has value that needs to be counted as a cost when assessing the merits of that program. In this paper, we develop a methodology for incorporating lost nonmarket time into benefit–cost analyses of social programs. We apply our methodology to the Self-Sufficiency Project (SSP), an experimental welfare-to-work program tested on a pilot basis in two provinces in Canada during the 1990s. We find that if losses in nonmarket time are ignored, SSP yields a substantial positive net benefit to society. However, if losses in nonmarket time are taken into account, the net societal benefits are greatly reduced, even becoming negative in certain instances. We conclude that future benefit–cost analyses of social programs must take effects on nonmarket time into account in order to give a more accurate picture of the net benefits of the program.
Dynamic fracture behavior of syntactic epoxy foams: optical measurements using coherent gradient sensing

Abstract Dynamic fracture behavior of syntactic foams made of thin-walled microballoons dispersed in epoxy matrix is studied. Monotonically decreasing dynamic Young's modulus with increasing volume fraction of microballoons is observed using ultrasonic pulse-echo and density measurements. The results are also in good agreement with the Hashin–Shtrikman lower-bound predictions for elastic porous solids. Dynamic crack initiation toughness and crack growth behaviors are examined using instrumented drop-tower tests and optical measurements. Crack initiation toughness shows a linear relationship with Young's modulus over the entire range of volume fraction of microballoons studied. A proposed model based on simple extension of micromechanics prediction agrees well with the measurements. The optical method of coherent gradient sensing (CGS) has been used along with high-speed photography to record crack tip deformation histories in syntactic foam samples subjected to impact loading. Pre- and post-crack initiation events have been successfully captured and apparent dynamic stress intensity factor histories are extracted from the interferograms. Results suggest increasing crack speeds with volume fraction of microballoons. No significant dependence of dynamic fracture toughness on crack speed in any of the volume fractions is observed.
The effects of propofol on cerebral perfusion MRI in children.

Introduction The effects of anesthesia are infrequently considered when interpreting pediatric perfusion magnetic resonance imaging (MRI). The objectives of this study were to test for measurable differences in MR measures of cerebral blood flow (CBF) and cerebral blood volume (CBV) between non-sedated and propofol-sedated children, and to identify influential factors.
Cell cycle and neuroepithelial cell shape during bending of the chick neural plate

Neuroepithelial cells change shape from spindle-like to wedge-like within three restricted areas (hinge points) of the bending neural plate. The mechanisms underlying these localized cell shape changes and the specific role that these changes play in bending are nuclear. This study was designed to determine whether changes in neuroepithelial cell shape involve basal cellular expansion owing to alteration of the cell cycle. Neurulating chick embryos were treated with colchicine to arrest and accumulate cells in metaphase, and colchicine indices and cell generation times were calculated for the neural plate. During bending of the neural plate, cell generation time in the median hinge point, which contains predominantly wedge-shaped cells, was significantly longer than that in adjacent lateral areas of the neural plate, which contain predominantly spindle-shaped cells. In addition, cell generation time in the flat neural plate, which contains predominantly spindle-shaped cells and has not yet differentiated into the median hinge point and lateral subdivisions, was identical to that in lateral areas of the bending neural plate but was significantly shorter than that in the median hinge point. These results support the hypothesis that changes in neuroepithelial cell shape from spindle-like to wedge-like involve basal cellular expansion owing to alteration of the cell cycle. Additional tests of this hypothesis and studies on the role of localized cell shape changes in neurulation are in progress.
How fast can photosystem II split water? Kinetic performance at high and low frequencies.

Molecular oxygen evolution from water is a universal signature of oxygenic photosynthesis. Detection of the presence, speed and efficiency of the enzymatic machinery that catalyzes this process in vivo has been limited. We describe a laser-based fast repetition rate fluorometer (FRRF) that allows highly accurate and rapid measurements of these properties via the kinetics of Chl-a variable fluorescence yield (Fv) in living cells and leaves at repetition rates up to 10 kHz. Application to the detection of quenching of Fv is described and compared to flash-induced O2 yield data. Period-four oscillations in both Fv and O2, caused by stimulation of primary charge recombination by the O2 evolving complex (WOC) within Photosystem II (PS II), are directly compared. The first quantitative calculations of the enzymatic parameters of the Kok model (α – miss; β – double hit; S-state populations) are reported from Fv data over a 5 kHz range of flash frequencies that is 100-fold wider than previously examined. Comparison of a few examples of cyanobacteria, green algae and spinach reveals that Arthrospira m., a cyanobacterium that thrives in alkaline carbonate lakes, exhibits the fastest water-splitting rates ever observed thus farin vivo. In all oxygenic phototrophs examined thus far, an unprecedented large increase in the Kok α and β parameters occur at both high and low flash frequencies, which together with their strong correlation, indicates that PS II-WOC centers split water at remarkably lower efficiencies and possibly by different mechanisms at these extreme flash frequencies. Revisions to the classic Kok model are anticipated.
Enhanced hysteresis in the semiconductor-to-metal phase transition of VO2 precipitates formed in SiO2 by ion implantation

A strongly enhanced hysteresis with a width of >34 °C has been observed in the semiconductor-to-metal phase transition of submicron-scale VO2 precipitates formed in the near-surface region of amorphous SiO2 by the stoichiometric coimplantation of vanadium and oxygen and subsequent thermal processing. This width is approximately an order of magnitude larger than that reported previously for the phase transition of VO2 particles formed in Al2O3 by a similar technique. The phase transition is accompanied by a significant change in infrared transmission. The anomalously wide hysteresis loop observed here for the VO2/SiO2 system can be exploited in optical data storage and switching applications in the infrared region.
CHLORIDE RETENTION IN EXPERIMENTAL HYDRONEPHROSIS

1. In acute experimental hydronephrosis chloride retention occurs as well as retention of water, urea, and phenolsulfonephthalein. 2. If both water and chlorides are retained there may be no appreciable rise in the plasma chloride content. 3. When chlorides are retained, but not water, the chloride content of the plasma rises strikingly. 4. After the removal of the ureteral obstruction in acute hydronephrosis all renal functions, water, urea, and chloride excretion, may be rapidly restored in equal degree, or the chlorides may be retained temporarily while there is free excretion of water and urea. 5. In chronic hydronephrosis adequate daily excretion of urea and chlorides may be maintained by a compensatory polyuria. 6. Chloride retention or an abnormal chloride excretion may occur in certain renal lesions when there is no change in the urea, phenolsulfonephthalein, or water excretion.
Phenomenological analysis for intrinsic properties of nonstoichiometric BaTiO3

The defect and phase equilibria of nonstoichiometric BaTiO3 have been systematically investigated. Self-consistent data were obtained and successfully modeled analytically with defect reactions taking into account the dependent variables of Ba/Ti ratio, temperature, and oxygen partial pressure (Po2). The compositional dependence of the ferroelectric properties in the solid solution regime was described by the Landau-Devonshire theory allowing the parameters of the theory to be functions of stoichiometry. With this approach, we are able to self-consistently determine the spontaneous polarization, dielectric constant, and energetics of the paraelectric-ferroelectric phase transition of powder samples. This theoretical approach provided a way of predicting the intrinsic properties of nonstoichiometric BaTiO3, which have had no previous complete determination or consideration.
Probing the mechanism of cyanobacterial aldehyde decarbonylase using a cyclopropyl aldehyde.

Cyanobacterial aldehyde decarbonylase (cAD) is a non-heme diiron oxygenase that catalyzes the conversion of fatty aldehydes to alkanes and formate. The mechanism of this chemically unusual reaction is poorly understood. We have investigated the mechanism of C1–C2 bond cleavage by cAD using a fatty aldehyde that incorporates a cyclopropyl group, which can act as a radical clock. When reacted with cAD, the cyclopropyl aldehyde produces 1-octadecene as the rearranged product, providing evidence for a radical mechanism for C–C bond scission. In an alternate pathway, the cyclopropyl aldehyde acts as a mechanism-based irreversible inhibitor of cAD through covalent binding of the alkyl chain to the enzyme.
Utility of the Mayo-Portland Adaptability Inventory-4 for Self-Reported Outcomes in a Military Sample With Traumatic Brain Injury

Abstract Objective To investigate the psychometric properties of the Mayo-Portland Adaptability Inventory-4 (MPAI-4) obtained by self-report in a large sample of active duty military personnel with traumatic brain injury (TBI). Design Consecutive cohort who completed the MPAI-4 as a part of a larger battery of clinical outcome measures at the time of intake to an outpatient brain injury clinic. Setting Medical center. Participants Consecutively referred sample of active duty military personnel (N=404) who suffered predominantly mild (n=355), but also moderate (n=37) and severe (n=12), TBI. Interventions Not applicable. Main Outcome Measure MPAI-4 Results Initial factor analysis suggested 2 salient dimensions. In subsequent analysis, the ratio of the first and second eigenvalues (6.84:1) and parallel analysis indicated sufficient unidimensionality in 26 retained items. Iterative Rasch analysis resulted in the rescaling of the measure and the removal of 5 additional items for poor fit. The items of the final 21-item Mayo-Portland Adaptability Inventory-military were locally independent, demonstrated monotonically increasing responses, adequately fit the item response model, and permitted the identification of nearly 5 statistically distinct levels of disability in the study population. Slight mistargeting of the population resulted in the global outcome, as measured by the Mayo-Portland Adaptability Inventory-military, tending to be less reflective of very mild levels of disability. Conclusions These data collected in a relatively large sample of active duty service members with TBI provide insight into the ability of patients to self-report functional impairment and the distinct effects of military deployment on outcome, providing important guidance for the meaningful measurement of outcome in this population.
Hemodynamic Evaluation of Rate Augmentation Produced by Atrial Pacing and Isoproterenol in the Early Postoperative Phase of Cardiac Valve Surgery

The hemodynamic effects of atrial pacing were evaluated in a group of 19 patients soon after cardiac valve surgery. Atrial pacing at 30 beats/min above the control rate of 88 beats/min produced an increase in cardiac index of 600 ml/min/m2. Isoproterenol was infused into eight of these patients to produce an increment in heart rate identical to that during atrial pacing. In these patients atrial pacing produced an increment in cardiac index of 400 ml/min/m2 as compared to an increment of 1400 ml/min/m2 produced by isoproterenol. It is concluded (1) that atrial pacing is a useful technique for augmenting cardiac index soon after cardiac valve surgery and (2) that isoproterenol provides a greater increment in cardiac index at identical heart rates and the major portion of its effect is directly inotropic.
Front line workers’ attitudes towards psychiatric advance directives

Studies have begun to explore provider attitudes’ toward psychiatric advance directives (PADs) and how those attitudes are related to provider characteristics. The study gathered attitudinal data from a sample of 193 social workers serving mentally ill adults. Social workers with pro-healthcare power of attorney (HCPA) attitudes were likely to have prior experience with an HCPA and to believe that involuntary treatment violates the NASW Code of Ethics. Social workers are more favorable of HCPAs than advance instructions. The findings suggest that clinical experiences with PADs may positively impact social worker’s perceptions of the law.
Subjective, physiological, and cognitive responses to intravenous nicotine: effects of sex and menstrual cycle phase.

Nicotine dependence is a serious public health concern. Optimal treatment of nicotine dependence will require greater understanding of the mechanisms that contribute to the maintenance of smoking behaviors. A growing literature indicates sex and menstrual phase differences in responses to nicotine. The aim of this study was to assess sex and menstrual phase influences on a broad range of measures of nicotine response including subjective drug effects, cognition, physiological responses, and symptoms of withdrawal, craving, and affect. Using a well-established intravenous nicotine paradigm and biochemical confirmation of overnight abstinence and menstrual cycle phase, analyses were performed to compare sex (age 18–50 years; 115 male and 45 female) and menstrual cycle phase (29 follicular and 16 luteal) effects. Females had diminished subjective drug effects of, but greater physiological responses to, nicotine administration. Luteal-phase females showed diminished subjective drug effects and better cognition relative to follicular-phase women. These findings offer candidate mechanisms through which the luteal phase, wherein progesterone is dominant relative to estradiol, may be protective against vulnerability to smoking.
Femoral bone adaptation to stable long-term cemented total hip arthroplasty in dogs.

Objective— To evaluate femoral adaptation after unstable long-term cemented total hip arthroplasty (cTHA) in dogs. Study Design— Clinical study. Animals— Four dogs. Methods— Paired femurs were examined from client-owned dogs that were donated to a retrieval program after death from causes unrelated to their cTHA. Mean (±SEM) dog age was 10.0±1.5 years and implant duration was 6.0±1.4 years. Implanted femurs had radiographic changes associated with implant loosening and gross mechanical instability at femur retrieval. Femurs were evaluated at 3 levels relative to implant length. Cortical area and medullary area were measured at each level, and cortical porosity was assessed at each level in 4 quadrants and in 3 regions. Implanted femurs were compared with the contralateral non-implanted femurs. Results— Cortical area and cortical porosity were increased at all levels in femurs with unstable implants. Implanted femurs had increased porosity in all quadrants and regions at the proximal 2 levels, and increased porosity in only the cranial quadrant and mid-cortical area at the distal level, when compared with contralateral non-implanted femurs. Corresponding medullary areas were not different. Conclusions— Significant histomorphometric changes occur in femurs after unstable cTHA. The patterns of periosteal bone formation and endosteal bone resorption support mechanisms of stress shielding and wear debris-mediated osteolysis as factors that may contribute to femoral adaptation and implant loosening. Clinical Relevance— Despite popularity and excellent return to function with cTHA, aseptic loosening remains a serious long-term complication. Substantial net bone loss and unfavorable environment with unstable cTHA may make revision surgery less successful.
Faecal calprotectin concentrations in untreated coeliac patients.

Objective. Calprotectin is a granulocyte cytosolic protein that is considered to be a promising marker of subclinical inflammation. High faecal calprotectin concentrations (FCCs) have been found in several intestinal diseases, but no data are currently available on patients with coeliac disease. The purpose of this pilot study was to evaluate FCCs in untreated coeliac patients and to correlate them with clinical score and histological characteristics. Material and methods. Twenty-eight consecutive coeliac patients were recruited. Thirty healthy adult volunteers participated as the control group. FCCs were determined by ELISA. Clinical assessment was carried out in all patients. The histological severity of lesions and the infiltration of neutrophil polymorphs in the intestinal mucosa were also evaluated. Mean FCCs in patients and the control group were compared by means of the t-test for independent samples. In coeliac patients, differences in FCCs in subgroups identified by clinical score, lesion severit...
Diabetic Complications of the Central Nervous System

Introduction DIABETES mellitus is a metabolic disorder associated with structural and functional alterations of various organ systems. The tissue injury is attributed primarily to chronic hyperglycemia. Although the peripheral neuropathy along with the small and large blood vessel disease can explain most of the diabetes-related organ failure, we have been increasingly more aware over the last two decades that the deleterious effects of chronic hyperglycemia extend beyond neuropathy and angiopathy. Examples of such diabetic complications include cataractous opacification of the lens (1–3), altered immune system (4–7), cardiomyopathy in the absence of appreciable intramural bloodvessel disease (8–10), alterations in specific transport functions of the intestine (11–16), and central nervous system (CNS) dysfunction. Thus glucotoxicity is not tissue specific, albeit the severity of organ system dysfunction in diabetes is highly variable. In contrast to the high prevalence rate of renal failure in diabetic pa...
Intrinsic Birefringence Signal Preceding the Onset of Contraction in Heart Muscle

An intrinsic birefringence signal with two components occurring before sarcomere shortening was measured in mammalian cardiac muscle. The second component was sensitive to the inotropic state of the muscle as affected by external calcium concentration and epinephrine but not by changes of resting length. The second component was absent in frog heart. These results suggest that the second component of the birefringence signal reflects the activity of the sarcoplasmic reticulum related to excitation-contraction coupling processes occurring prior to onset of contraction in mammalian cardiac muscle.
New Directions in Artificial Intelligence for Public Health Surveillance

The next decade of disease surveillance research will require novel methods to effectively use massive quantities of complex, high-dimensional data. We summarize two recent approaches which deal with the increasing complexity and scale of health data, including the use of rich text data to detect emerging outbreaks with novel symptom patterns, and fast subset scan methods to efficiently identify the most relevant patterns in massive datasets.
Coupled vibration of nonlinear breathing cracked rotor in lateral, torsional, and longitudinal DOFs

In this paper, finite element model of a shaft-disk system is developed to investigate the nonlinear breathing behavior of transverse cracks in terms of crack location and rotation speed. The crack model is built using the released strain energy concept in fracture mechanics. Zero Stress Intensity Factor (SIF) method is employed to determine the crack closure line at each time step by calculating the stress intensity factor of opening mode for prescribed resolutions in crack area. The stiffness matrix is updated every time step by integrating compliant coefficients over instantly calculated crack open area. With the finite element model of rotor system, the breathing behavior of cracks is explored as a function of eccentricity phase under different rotation speeds. The coupling of lateral, longitudinal and torsional vibration is studied in time and frequency domain, which may indicate the existence of damage.
DLPC and SAMe combined prevent leptin‐stimulated TIMP‐1 production in LX‐2 human hepatic stellate cells by inhibiting H2O2‐mediated signal transduction

: Background/Aims: Both dilinoleoylphosphatidylcholine (DLPC) and S-adenosylmethionine (SAMe) have antioxidant properties and antifibrogenic actions. Because H2O2 mediates signal transduction-stimulating liver fibrogenesis, we investigated whether DLPC and SAMe attenuate the production of tissue inhibitor of metalloproteinase (TIMP)-1 by inhibiting H2O2 formation. Methods: LX-2 human hepatic stellate cells were treated with leptin with or without DLPC, SAMe or various inhibitors. Results: Leptin-stimulated TIMP-1 mRNA and its protein were diminished by DLPC or SAMe alone, and the response was fully prevented by the combination of DLPC and SAMe. H2O2 was increased while glutathione was decreased; these changes were prevented by AG490, suggesting a Janus kinases (JAK)-mediated process. Up-regulation of leptin receptor and activation of JAK1 and 2 were not affected by DLPC+SAMe, whereas phosphorylation of ERK1/2 and p38 was blocked by DLPC+SAMe or catalase, suggesting an H2O2-dependent mechanism. These treatments also suppressed leptin-stimulated TIMP-1 promoter activity and decreased TIMP-1 mRNA stability, contributing to TIMP-1 mRNA down-regulation. PD098059, an ERK1/2 inhibitor, suppressed TIMP-1 promoter activity, whereas SB203580, a p38 inhibitor, decreased TIMP-1 message stability; both resulted in a partial reduction of TIMP-1 mRNA. Conclusion: As decreased TIMP-1 production may enhance collagen deposition, the combined administration of DLPC+SAMe should be considered for the prevention of H2O2-mediated signaling and the resulting fibrosis.
The Victim-Bind Dilemma of Black Female Sociologists in Academe.

In this article, the author argues that black female academicians, in particular sociologists, are in a “victim-bind,” which indicates their paradoxical ambivalence and produces stereotypical perceptions. This article examines the purpose and functions of stereotypic perceptions of black females in various phases of graduate school and early career development. It draws on the limited literature as well as the experiences and observations of the author and points out how the political culture and institutional structures of academic communities and departments shape images and career patterns of black women being professionalized as sociologists and social scientists in general. It concludes that stereotypic perceptions of black females are tied into the institutional systems of gender, race and power relations which represent in microcosm, the society at large.
Wall deposition of aerosol particles in a turbulent channel flow

Abstract Motion of small suspended particles in a turbulent channel flow is studied. The mean flow field is simulated using a two-equation κ-e turbulence model. Trajectories of aerosol particles in the channel are evaluated by solving the corresponding Lagrangian equation of motion, which includes the effects of Brownian motion and turbulence fluctuations. Simulations are carried out for aerosol particles (of various sizes) released at different locations across the channel. Depositions of particles on the channel wall for several flow Reynolds numbers and different inlet turbulence intensity are evaluated. The results show that turbulence fluctuations dominate the particle dispersion and deposition processes. The deposition rate is shown to increase as the flow Reynolds number or the inlet flow turbulence intensity increases. The Brownian effects become significant for particles smaller than 1 μ.
Spectral Tilt Change in Stop Consonant Perception by Listeners With Hearing Impairment

Purpose To evaluate how perceptual importance of spectral tilt is altered when formant information is degraded by sensorineural hearing loss. Method Eighteen listeners with mild to moderate hearing...
Dimensions and Geometric Relationships of the Human Aortic Value as a Function of Pressure

In a continuing effort to develop improved prosthetic heart valves, a redefinition of the anatomy of the human aortic valve as a function of stress was undertaken. Dimensions and geometric relationships of the human aortic valve as a function of intraaortic pressure between 0 and 120 mm Hg were obtained from a series of silicone rubber valve casts. The axial length of the valve region was found to vary negligibly with pressure, but significant variations in geometry and angular dimensions were seen. The leaflet attachment annulus forms an ellipse at the plane of intersection with the cylindrical surface passing from the left ventricular tract through the aorta. Deductions from stress considerations for the measured geometry indicate that the loaded leaflet is a section of a cylindrical surface. The equation for this developed surface was obtained, and a prosthetic design was determined using average values at 100 mm Hg. The leaflet is developable onto a plane with a cut required along part of the junction...