cssi/SciSciGPT-SciSciNet huggingface dataset:
Murine intrarectal instillation of purified recombinant C. difficile toxins enables mechanistic studies of pathogenesis

Abstract Clostridioides difficile is linked to nearly 225,000 antibiotic-associated diarrheal infections and almost 13,000 deaths per year in the United States. Pathogenic strains of C. difficile produce toxin A (TcdA) and toxin B (TcdB), which can directly kill cells and induce an inflammatory response in the colonic mucosa. Hirota, et al. first introduced the intrarectal instillation model of intoxication using TcdA and TcdB purified from VPI 10463 and 630 C. difficile strains. Here, we expand this technique by instilling purified, recombinant TcdA and TcdB, which allows for the interrogation of how specifically mutated toxins affect tissue. Mouse colons were processed and stained with hematoxylin and eosin (H&E) for blinded evaluation and scoring by a board-certified gastrointestinal pathologist. The amount of TcdA or TcdB needed to produce damage was lower than previously reported in vivo and ex vivo. Furthermore, TcdB mutants lacking either endosomal pore-formation or glucosyltransferase activity resemble sham negative controls. Immunofluorescent staining revealed how TcdB initially damages colonic tissue by altering the epithelial architecture closest to the lumen. Tissue sections were also immunostained for markers of acute inflammatory infiltration. These staining patterns were compared with slides from a human C. difficile infection (CDI). The intrarectal instillation mouse model with purified recombinant TcdA and/or TcdB provides the flexibility needed to better understand structure/function relationships across different stages of CDI pathogenesis.
Impact of topology and congestion on link criticality rankings in transportation networks

Abstract Due to the lack of ground truth on the link criticality rankings of transportation networks, it is not possible to identify the most accurate metric. While several studies provide reviews of the existing criticality metrics, the consistencies of calculated rankings by these metrics are yet to be explored. In this paper, link criticality rankings with five different metrics are compared under 150 test networks of different network topologies and congestion levels. Accordingly, the consensus metric that provides a ranking that is closest to the aggregate ranking is identified for each test network. The results show transportation network efficiency metric is the most frequent consensus metric and link flow can serve as proxy for criticality analysis under certain network characteristics. The level of congestion and network transitivity are the most important features to determine the consensus metric. The proposed framework is then tested on Sioux Falls, Eastern Massachusetts, and Anaheim networks.
Escaping Poverty & Becoming Self-Sufficient

Using logistic regression analysis on data from the National Longitudinal Survey of Youth, this study found that sociodemographic factors were far more influential in determining escape from poverty and becoming self-sufficient than social psychological factors. The number of years respondents lived in poverty was the best predictor of escaping poverty, while the number of years respondents made use of public assistance programs was the best predictor of becoming self-sufficient. Marital status and change in the number of hours worked influenced the prospect for escaping poverty, though not becoming self-suffcient. Implications regarding the changing philosophy of social welfare from income maintenance to self-sufficiency are discussed
Fiscal federalism and government size in transition economies: the case of Moldova

This paper examines the relationship between fiscal decentralization—the assignment of revenue sources and expenditure functions across government levels—and government size in Moldova. The empirical results—based on data for a cross-section of Moldovan sub-national government in 1998—suggest that fiscal decentralization is associated with larger sub-national governments and that the country's revenue-sharing system imposes a constraint on sub-national revenue mobilization capacity. Copyright © 2001 John Wiley & Sons, Ltd.
Wireless sensor networks

A wireless sensor network comprises at least one sensor unit which comprises a sensor for sensing a parameter and at least one interrogating node. The interrogating node is arranged to transmit an interrogation message periodically to said sensor unit and to receive a reply message from said sensor unit. The sensor unit is arranged to transmit said reply message after a predetermined deliberate delay unless the sensor unit determines that an alarm condition has been met, in which case the sensor unit is arranged to transmit said reply message before the end of the deliberate delay.
Revascularization for asymptomatic carotid artery stenosis improves balance and mobility

Abstract Objective Balance and mobility function worsen with age, more so for those with underlying chronic diseases. We recently found that asymptomatic carotid artery stenosis (ACAS) restricts blood flow to the brain and might also contribute to balance and mobility impairment. In the present study, we tested the hypothesis that ACAS is a modifiable risk factor for balance and mobility impairment. Our goal was to assess the effect of restoring blood flow to the brain by carotid revascularization on the balance and mobility of patients with high-grade ACAS (≥70% diameter-reducing stenosis). Methods Twenty adults (age, 67.0 ± 9.4 years) undergoing carotid endarterectomy for high-grade stenosis were enrolled. Balance and mobility assessments were performed before and 6 weeks after revascularization. These included the Short Physical Performance Battery, the Berg Balance Scale, the Four Square Step Test, the Dynamic Gait Index (DGI), the Timed Up and Go test, gait speed, the Mini-Balance Evaluation Systems Test (Mini-BESTest), and the Walking While Talking complex test. Results Consistent with our previous findings, patients demonstrated reduced scores on the Short Physical Performance Battery, Berg Balance Scale, DGI, and Timed Up and Go test and in gait speed. Depending on the outcome measure, 25% to 90% of the patients had scored in the impaired range at baseline. After surgery, significant improvements were observed in the outcome measures that combined walking with dynamic movements, including the DGI (P = .02) and Mini-BESTest (P = .002). The proportion of patients with Mini-BESTest scores indicating a high fall risk had decreased significantly from 90% (n = 18) at baseline to 40% (n = 8) after surgery (P = .02). We used Pearson's correlations to examine the relationship between balance and mobility before surgery and the change after surgery. Patients with lower baseline DGI and Mini-BESTest scores demonstrated the most improvement after surgery (r = −0.59, P = .006; and r = −0.70, P = .001, respectively). Conclusions Carotid revascularization improved patients' balance and mobility, especially for measures that combine walking and dynamic movements. The greatest improvements were observed for the patients who had been most impaired at baseline.
Aging Delays Epimorphic Regeneration in Mice

Epimorphic regeneration is a multi-tissue regeneration process where amputation does not lead to scarring, but blastema formation and patterned morphogenesis for which cell plasticity and concerted cell-cell interactions are pivotal. Tissue regeneration declines with aging, yet if and how aging impairs epimorphic regeneration is unknown. Here we show for the first time that aging derails the spatiotemporal regulation of epimorphic regeneration in mammals, first, by exacerbating tissue histolysis and delaying wound closure, and second, by impairing blastema differentiation and skeletal regrowth. Surprisingly, aging did not limit stem cell availability in the blastema, but reduced osteoblast-dependent bone formation. Our data suggest that aging delays regeneration not by stem cell exhaustion, but functional defects of differentiated cells that may be driven by an aged wound environment and alterations in the spatiotemporal regulation of regeneration events. Our findings emphasize the importance of accurate timing of signaling events for regeneration, and highlight the need for carefully timed interventions in regenerative medicine.
Bringing Them In or Pushing Them Out? The Labor Market Effects of Pro-cyclical Unemployment Assistance Reductions

We exploit variation from an unanticipated labor market reform in 2012 Spain to causally estimate the effects of pro-cyclical unemployment assistance (UA) reductions on job search behavior and re-employment outcomes. Shorter benefit durations effectively bring individuals back to work and reduce non-employment duration. However, they also induce displacements out of the labor force and strong substitution patterns towards other, less generous, welfare programs, highlighting the social insurance role of long-term benefits during economic downturns. Despite the sharp drop in non-employment duration, we also document a significant decrease in re-employment wages, consistent with reduced workers' reservation wages and limited duration dependence. Heterogeneity analyses show that relatively younger workers are the ones that are brought back into re-employment in lower-quality jobs, while older workers are pushed out of the labor force. Looking at responses over the non-employment spell, we provide evidence against the standard assumption of forward-looking behavior of benefit recipients, as we do not detect any change in workers' behavior before benefit exhaustion. Overall, we estimate that the reform induced only moderate fiscal savings for the government.
A multidisciplinary study of the 'yips' phenomenon in golf: An exploratory analysis.

Background: The ‘yips’ is a psychoneuromuscular impediment affecting execution of the putting stroke in golf. Yips symptoms of jerks, tremors and freezing often occur during tournament golf and may cause performance problems. Yips-affected golfers add approximately 4.7 strokes to their scores for 18 holes of golf, and have more forearm electromyogram activity and higher competitive anxiety than nonaffected golfers in both high and low anxiety putting conditions. The aetiology of the yips is not clear. Objective: To determine whether the yips is a neurological problem exacerbated by anxiety, or whether the behaviour is initiated by anxiety and results in a permanent neuromuscular impediment. Methods: In phase I, golf professionals assisted investigators in developing a yips questionnaire that was sent to tournament players (<12 handicap) to establish the prevalence and characteristics of the yips. Phase II measured putting behaviour in scenarios that contribute to the yips response. Four self-reported yips and 3 nonaffected golfers putted 3 scenarios using an uncorrected grip and a standard length putter. Heart rate was superimposed on the videotape and the putter grip was instrumented with strain gauges to measure grip force. Electromyograms and relative putting performance were also measured. Results: The questionnaire was sent to 2630 tournament players, of whom 1031 (39%) responded (986 men and 45 women). Of these, 541 (52%) perceived they experienced the yips compared with 490 (48%) who did not.Yips-affected golfers reported that the most troublesome putts were 3, 4 and 2 feet (0.9, 1.2 and 0.6 metres) from the hole. Fast, downhill, left-to-right breaking putts and tournament play also elicited the yips response. Golfers affected by the yips had a faster mean heart rate, increased electromyogram activity patterns and exerted more grip force than nonaffected golfers and had a poorer putting performance. Conclusions: For <10 handicap male golfers and <12 handicap female golfers, the prevalence of the yips is between 32.5% and 47.7%, a high proportion of serious golfers. This high prevalence suggests that medical practitioners need to understand the aetiology of the yips phenomenon so that interventions can be identified and tested for effectiveness in alleviating symptoms. Although previous investigators concluded that the yips is a neuromuscular impediment aggravated but not caused by anxiety, we believe the yips represents a continuum on which ‘choking’ (anxiety-related) and dystonia symptoms anchor the extremes. The aetiology may well be an interaction of psychoneuromuscular influences. Future research to test the effect of medications such as β-blockers should assist in better identifying the contributions these factors make to the yips phenomenon.
Monolayer-protected gold nanoparticles as an efficient stationary phase for open tubular gas chromatography using a square capillary: Model for chip-based gas chromatography in square cornered microfabricated channels

Abstract The application of a dodecanethiol monolayer-protected gold nanoparticle (MPN) stationary phase within a microchannel environment was explored using a square capillary column as a model for high-speed, microfabricated gas chromatography (μGC). Successful deposition and evaluation of a dodecanethiol MPN phase within a 1.3 m long, 100 μm ×100 μm square capillary is reported. The thickness of the MPN phase was evaluated using SEM analysis. An average thickness of 15 nm along the capillary walls was determined. While the film depth along the walls was very uniform, the corner depths were greater with the largest observed depth being 430 nm. Overall, an efficient chromatographic system was obtained with a minimum reduced plate height, hmin, of 1.2 for octane (k=0.22). Characterization of the MPN column was completed using four compound classes (alkanes, alcohols, ketones, and aromatics) that were used to form a seven-component mixture with a 2-s separation. A mixture consisting of a nerve agent simulant in a sample containing analytes that may commonly interfere with detection was also separated in only 2 s, much faster than a similar separation previously reported using a μGC system requiring 50 s. A comparison of the MPN stationary phase to phases employed in previously reported μGC systems is also made. Application of the square capillary MPN column for a high-speed separation as the second column of a comprehensive 2-D gas chromatography system (GC×GC) was also explored.
Binding of TBP to promoters in vivo is stimulated by activators and requires Pol II holoenzyme

In eukaryotes, transcriptional activators have been proposed to function by recruiting the RNA polymerase II (Pol II) machinery, by altering the conformation of this machinery, or by affecting steps after initiation, but the evidence is not definitive. Genomic footprinting of yeast TATA-box elements reveals activator-dependent alterations of chromatin structure and activator-independent protection, but little is known about the association of specific components of the Pol II machinery with promoters in vivo. Here we analyse TATA-box-binding-protein (TBP) occupancy of 30 yeast promoters in vivo. We find that TBP association with promoters is stimulated by activators and inhibited by the Cyc8-Tup1 repressor, and that transcriptional activity correlates strongly with the degree of TBP occupancy. In a small subset of promoters, TBP occupancy is higher than expected when gene activity is low, and the activator-dependent increase is modest. TBP association depends on the Pol II holoenzyme component Srb4, but not on the Kin28 subunit of the transcription factor TFIIH, even though both proteins are generally required for transcription. Thus in yeast cells, TBP association with promoters occurs in concert with the Pol II holoenzyme, activator-dependent recruitment of the Pol II machinery occurs at the vast majority of promoters, and Kin28 acts after the initial recruitment.
Treatment of myocardial abnormalities with laser therapy

Laser angioplasty using excimer lasers at 308 nm is approved for treatment of sphenous bypass grafts, ostial lesions, long lesions (>20 mm), moderately calcific lesions, total occlusions traversable by a guide wire, and lesions which have previously failed balloon angioplasty. Limitations of this technology include arterial dissection (20%) and a small lumen site. Direct myocardial perfusion by transmyocardial revascularization (TMR) with lasers is currently undergoing clinical investigation. The feasibility of revascularization of areas of the myocardium which cannot be bypassed may provide additional means for reperfusion. Basic studies currently being done have demonstrated benefit after several weeks following the TMR procedure.
Oral bioavailability of P-glycoprotein substrate drugs do not differ between ABCB1-1Δ and ABCB1 wild type dogs

Mealey, K.L., Waiting, D., Raunig, D.L., Schmidt, K.R., Nelson, F.R. Oral bioavailability of P-glycoprotein substrate drugs do not differ between ABCB1-1Δ and ABCB1 wild type dogs. J. vet. Pharmacol. Therap. 33, 453–460. Previous studies have indicated that intestinal P-glycoprotein (P-gp) limits the oral bioavailability of substrate drugs and alters systemic pharmacokinetics. In this study, dogs lacking functional P-gp were used to determine the contribution of P-gp to the oral bioavailability and systemic pharmacokinetics of several P-gp substrate drugs. The P-gp substrates quinidine, loperamide, nelfinavir, cyclosporin and the control (non P-gp substrate) drug diazepam were individually administered intravenously and per os to ABCB1-1Δ dogs, which have a P-gp null phenotype and ABCB1 wildtype dogs. ABCB1-1Δ dogs have been shown to have greater brain penetration of P-gp substrates, but limited information is available regarding oral bioavailability of P-gp substrate drugs in this animal model. Plasma drug concentration vs. time curves were generated and pharmacokinetic parameters were calculated for each drug. There were no differences in oral bioavailability between ABCB1-1Δ dogs and ABCB1 wildtype dogs for any of the drugs studied, suggesting that intestinal P-gp does not significantly affect intestinal absorption of these particular substrate drugs in ABCB1-1Δ dogs. However, small sample sizes and individual variability in CYP enzyme activity may have affected the power of the study to detect the impact of P-gp on oral bioavailability.
Transcriptional activation of genes by 17 beta-estradiol through estrogen receptor-Sp1 interactions.

Estrogen receptor-α (ERα) is a ligand-activated transcription factor and a member of the nuclear receptor superfamily. The classic mechanism of (ERα) action is associated with estrogen-induced formation of a nuclear (ERα) homodimer, binding to 5′-regulatory estrogen response elements (EREs) in target gene promoters, interaction with other nuclear proteins, and general transcription factors to activate gene expression. (ERα) also interacts with Sp1 protein to transactivate genes through binding Sp1(N)xERE or Sp1(N)xERE half-site (12) motifs where both (ERα) and Sp1 bind DNA elements. Activation through Sp1 (N)xERE12 requires interactions of both proteins with their cognate DNA elements as well as additional nuclear factors to form a functional ERα/Sp1-DNA complex. Recent studies also show that (ERα) and Sp1 physically interact and (ERα) preferentially binds to the C-terminal DNA-binding domain of Sp1 protein. Moreover, ERα/Sp1 can activate transcription from a consensus GC-rich Sp1 binding site in transient transfection studies in MCF-7 human breast cancer cells, and this response is also observed with ERα variants that do not contain the DNA-binding domain. Several genes that are induced by estrogens in MCF-7 cells are activated through one or more GC-rich sites in their regulatory regions and these include the cathepsin D, E2F1, bcl-2, c-fos, adenosine deaminase, insulinlike growth factor binding protein 4, and retinoic acid receptor α1 genes. ERα/Sp1 and ERβ/Sp1 action is dependent on ligand structure and cell context and ERβ/Sp1 is primarily associated with decreased ligand-dependent gene expression. ERα/Sp1, like ERα/AP1, represents a pathway for hormone activation of genes in which the receptor does not bind DNA, and results of ongoing studies suggest that ERα/Sp1 plays an important role in transcriptional activation of multiple growth regulatory genes in breast cancer cells.
Human TMEM30a Promotes Uptake of Antitumor and Bioactive Choline Phospholipids into Mammalian Cells

Antitumor alkylphospholipids initiate apoptosis in transformed HL-60 and Jurkat cells while sparing their progenitors. 1- O -Alkyl-2-carboxymethyl- sn -glycero-3-phosphocholine (Edelfosine) like other short-chained phospholipids—inflammatory platelet-activating factor (PAF) and apoptotic oxidatively truncated phospholipids—are proposed to have intracellular sites of action, yet a conduit for these choline phospholipids into mammalian cells is undefined. Edelfosine is also accumulated by Saccharomyces cerevisiae in a process requiring the membrane protein Lem3p, and the human genome contains a Lem3p homolog TMEM30a. We show that import of choline phospholipids into S. cerevisiae ΔLem3 is partially reconstituted by human TMEM30a and by Lem3p-TMEM30a chimeras, showing the proteins are orthologous. TMEM30a–GFP chimeras expressed in mammalian cells localized in plasma membranes, as well as internal organelles, and ectopic TMEM30a expression promoted uptake of exogenous choline and ethanolamine phospholipids. Short hairpin RNA knockdown of TMEM30a reduced fluorescent choline phospholipid and [ 3 H]PAF import. This knockdown also reduced mitochondrial depolarization from exogenous Edelfosine or the mitotoxic oxidatively truncated phospholipid azelaoyl phosphatidylcholine, and the knockdown reduced apoptosis in response to these two phospholipids. These results show that extracellular choline phospholipids with short sn -2 residues can have intracellular roles and sites of metabolism because they are transport substrates for a TMEM30a phospholipid import system. Variation in this mechanism could limit sensitivity to short chain choline phospholipids such as Edelfosine, PAF, and proapoptotic phospholipids.
Platelets and Coagulation: An Update

The latest developments in the areas of platelets and coagulation are presented and related to physiologic and pathologic processes. Platelet integrins, particularly α IIb β 3 , are discussed and their role in normal platelet aggregation, immune-mediated platelet destruction, and tumor cell metastasis are presented. New perspectives on coagulation pathways, mechanisms of antiphospholipid syndrome, and progress in hemophilia gene therapy are also discussed.
Spline-based controller for power system stability enhancement

The objective of this paper is to design nonlinear excitation controllers for power system stability enhancement. First the direct feedback linearization method is applied to design the excitation controllers. But these controllers have complex structures. Hence, spline techniques are then used to approximate the nonlinear controllers obtained through feedback linearization by polynomials of different degrees and minimize the control effort and yet get a performance similar to the one obtained with the complex nonlinear controllers. A three machine nine bus power system is used as a test system to illustrate the proposed controllers. Simulation results demonstrate that the controllers are effective under different disturbances such as loss of a line and a line to ground fault.
Heteropoly acid-catalyzed microwave-assisted three-component aza-Diels–Alder cyclizations: diastereoselective synthesis of potential drug candidates for Alzheimer's disease

A highly diastereoselective microwave-assisted three component synthesis of azabicyclo[2.2.2]octan-5-ones by a silicotungstic acid-catalyzed aza-Diels–Alder cyclization is described. The one-pot process involves the formation of the in situ generated Schiff base and its immediate cyclization with cyclohex-2-enone. The short reaction times, good yields and excellent diastereoselectivity make this annulation a practical and environmentally attractive method for the synthesis of the target compounds. Preliminary assays were carried out to determine the activity of the products in AChE as well as in amyloid β fibrillogenesis inhibition.
Application of Artificial Intelligence (AI) Programming Techniques to Tactical Guidance For Fighter Aircraft

A research program investigating the use of Artificial Intelligence (AI) techniques to aid in the development of a Tactical Decision Generator (TDG) for Within-Visual-Range (WVR) air combat engagements is discussed. The application of AI methods for development and implementation of the TDG is presented. The history of the Adaptive Maneuvering Logic (AML) program is traced and current versions of the AML program are compared and contrasted with the TDG system. The Knowledge-Based Systems (KBS) used by the TDG to aid in the decision-making process are outlined in detail and example rules are presented. The results of tests to evaluate the performance of the TDG versus a version of AML and versus human pilots in the Langley Differential Maneuvering Simulator (DMS) are presented. To date, these results have shown significant performance gains in one-versus-one air combat engagements, and the AI-based TDG software has proven to be much easier to modify than the updated FORTRAN AML programs.
L-Arginine Does Not Restore Dilatation of the Basilar Artery during Diabetes Mellitus:

The goal of this study was to test the hypothesis that administration of L-arginine, a substrate for the synthesis of nitric oxide, restores endothelium-dependent dilatation of the basilar artery during diabetes mellitus. We measured the diameter, of the basilar artery in vivo in nondiabetic and diabetic (streptozotocin; 50-60 mg/kg i.p.) rats in response to endothelium-dependent agonists (acetylcholine and bradykinin) and an endothelium-independent agonist (nitroglycerin) before and during application of L-arginine. Topical application of acetylcholine (1.0 and 10 muM) and bradykinin (1.0 and 10 microM) produced dilatation in nondiabetic rats of the basilar artery which was impaired in diabetic rats. Topical application of nitroglycerin (0.1 and 1.0 microM) produced similar dilatation of the basilar artery in nondiabetic and diabetic rats. Topical application of L-arginine (0.1 and 3 mM) did not enhance dilatation of the basilar artery in response to acetylcholine and bradykinin in diabetic rats. Thus, impairment of dilatation of the basilar artery in diabetic rats in response to acetylcholine and bradykinin appears to be related to a mechanism unrelated to the availability of L-arginine for nitric oxide synthase.
The Analysis of Activity Networks Under Generalized Precedence Relations GPRs

We present a model for activity networks under generalized precedence relations GPRs, discuss its temporal analysis and the issues that may arise relative to inconsistency among the specified relations and the activity durations. We also give more precise definition to the concept of criticality of an activity, and introduce the new concept of flexibility of an activity which is akin to the traditional concept of activity floats in regular CPM, with the latter taking on different meaning from its common interpretation in standard CPM. Issues of optimization are raised when one assumes, for each activity, a piecewise-linear time-cost function that permits positive and negative deviations from its least-cost duration between specified lower and upper bounds on that duration. We seek the optimal activity durations subject to the specified GPRs and a given due date λ. We also seek the construction of the complete project duration-cost function between the project minimum duration and its least-cost duration when the due date λ is interpreted, first, as a "deadline" and, second, as a "target date" with rewards for early, and penalties for late completion. The relations between the problems posed and the uncapacitated minimum cost flow problems are revealed and are utilized in the algorithmic solution of the problems.
Repetition, cuing, and state-dependent memory.

Two experiments examined the effects of several types of repetition on state-dependent memory for conceptually categorized words. In both experiments, compatibility between pharmacological states at encoding and at retrieval facilitated the uncued recall of nonrepeated categories but had no appreciable effect on the recall of words within recalled categories. In both experiments, compatibility between encoding/retrieval states failed to facilitate the uncued recall of repeated categories li.e., categories whose names and/or exemplars were presented at least twice, in a constant or variable order, and with substantial spacing between successive presentations). And again, in both experiments, the level of uncued recall was higher for repeated than for nonrepeated categories, irrespective of the compatibility or incompatibility of encoding/retrieval states. These findings, together with other relevant observations reported in the literature, suggest that repetition in general, and repetition of category names in particular, influences recall in much the same ways as does explicit cuing with category names: It enhances the accessibility of higher order units, as reflected in uncued category recall, and it diminishes to the extent to which access to these units is state dependent.
A Low Computational Cost Nonlinear Formulation for Multibody Railroad Vehicle Systems

In this investigation, a multibody system formulation for the nonlinear dynamics of railroad vehicles is developed. This formulation, which permits developing simplified models for the forces acting on rail cars, allows the analysis of long trains at a low computational cost. In the dynamic models developed using the formulation proposed in this investigation, each rail car can be represented as a single rigid body. The configurations of the bodies in a train model are defined with respect to trajectory coordinate systems which follow a space curve whose geometry is defined at a preprocessing stage. In the formulation presented in this study, the number of degrees of freedom of an arbitrary body can be varied from one to six degrees of freedom. The principal degree of freedom of an arbitrary body is the arc length along the space curve. This degree of freedom defines the location of the origin and the orientation of the body trajectory coordinate system. The other five degrees of freedom define the location and orientation of the body with respect to the body trajectory coordinate system. The nonlinear equations of motion of the bodies in a train model are developed using the three-dimensional Newton-Euler equations. These equations are then expressed in terms of the trajectory coordinates and their derivatives. To this end, a velocity transformation is obtained by expressing the Cartesian and angular velocities of the bodies in terms of the time derivatives of the trajectory coordinates. Various force element models particular to rail cars are developed in this study. These forces include tractive effort, and air brake and dynamic brake forces, as well as a model of available wheel-rail adhesion. Additionally, various types of couplers are formulated as force elements, allowing the modeling of connections between cars. Resistance forces are also modeled in order to be able to simulate rolling, curve, and air resistance forces that may act on the cars during the train operations.Copyright © 2007 by ASME
The dark side of the boon? Credibility, selective exposure and the proliferation of online sources of political information

Abstract While the media industry may consider credibility its most valuable asset, scholars suggest there is a potential “dark side” to credibility: Perceptions of credibility of a source lead to selective exposure and selective avoidance, and both lead to increased fragmentation and polarization of social and political views. The link between credibility and selective exposure and avoidance has not received much academic attention, therefore this study employed a survey of politically interested Internet users during the 2008 presidential campaign to test the influence of credibility and reliance on selective exposure and avoidance after controlling for demographic and political factors. This study found little evidence of a dark side to credibility. Respondents who judge blogs as credible search for information that supports their point of view, as well as challenges their opinions.
Asymptotic entropy, periodic orbits, and pseudo-Anosov maps

In this paper we derive some properties of a variety of entropy that measures rotational complexity of annulus homeomorphisms, called asymptotic or rotational entropy. In previous work [KS] the authors showed that positive asymptotic entropy implies the existence of infinitely many periodic orbits corresponding to an interval of rotation numbers. In our main result, we show that a Holder ) homeomorphism with nonzero asymptotic entropy.
A laser microprobe, mass spectrometric study of Ar, Kr, K, Cl and Br in an “unconformity garnet”, associated fluid inclusions, staurolite and micas from Vermont, U.S.A.

Abstract Garnet prophyroblasts in paragonite schist of the Pinney Hollow Fm. on the west limb of the Athens mantled gneiss dome in Vermont exhibit apparent angular unconformities. Cores of garnets contain inclusions of chloritoid, rutile and ilmenite that define a foliation which is truncated at a high angle by the foliation in the rims. Electron microprobe traverses across a garnet indicate that the core-rim boundary is the beginning of a steep compositional gradient in Ca, Mg, Mn and Fe that characterizes the rim. Following electron microprobe study, a sample was irradiated in a nuclear pile and then studied by laser microprobe noble gas mass spectrometry. Ar isotopes were measured in garnet and in adjacent micas and staurolite, and Ar plus Kr isotopes were measured in fluid inclusions (FI) in quartz. In garnet and in FI, trapped 40 Ar 36 Ar varies between ∼ 300 and 2000, with no simple correlations indicated between trapped Ar isotope ratios and K, Cl and 84Kr or petrographic features. Similar trapped Ar occurs in the core and rim of garnet and in FI in quartz. Most FI indicate 40 Ar e Cl > 10 −3 and Cl 36 Ar 6 (atom ratios). Br abundances in FI are usually too low to be measured, indicating Br Cl −3 (atom ratio). 84 Kr 36 Ar in FI varies between ∼ 0.02 and ∼ 0.08. Gases extracted from laser craters in white micas in schist outside the garnet indicate mean 40 Ar 39 Ar ages of 362 ± 5 Ma and in biotites 332 ± 7 Ma, with K-bearing inclusions in the garnet rim yielding ages close to 360 Ma. In the garnet core, interpretation of 40 Ar 39 Ar ages is ambiguous due to the combination of low concentrations of in situ radiogenic 40Ar and comparatively large amounts of trapped 40Are poorly correlated with other parameters measured.
Decreased Myocardial Gene Expression of Glucose Transporter 1 (GLUT1) and Glucose Transporter 4 (GLUT4) in Adult Intrauterine Growth Retarded (IUGR) Rats ♦ 494

Asymmetrical IUGR is associated with an increased prevalence and mortality of coronary artery disease in adult males. These adult males are characterized by hypertension, hyperlipidemia, and insulin resistance/NIDDM (Syndrome X). Syndrome X individuals exhibit decreased insulin stimulated glucose uptake in cardiac and skeletal muscle. The molecular basis for the cardiac insulin resistance is unknown. Transport of glucose across membranes is controlled by the glucose transporters (GLUT), a family of 7 structurally similar proteins. GLUT1 and GLUT4 are the predominant isoforms expressed in cardiac muscle. In cardiac muscle, both GLUT1 and GLUT4 are insulin sensitive. We therefore hypothesized that GLUT1 and GLUT4 gene expression would be decreased in adult male IUGR cardiac muscle. We performed maternal bilateral uterine artery ligation (a well characterized model of placental insufficiency and asymmetrical IUGR) and sham surgery (C) in pregnant rats on day 19 of gestation (term-21d). Litters are culled to 6 at birth. Male cardiac tissue was harvested at 120 days of life, and RNA and protein were isolated. GLUT1 and GLUT4 mRNA levels were quantitated using RT-PCR with an internal control, and GLUT1 and GLUT4 protein levels were quantitated by western blotting. RESULTS: Both GLUT1 mRNA and protein were significantly decreased in IUGR hearts (C= 1.O, IUGR GLUT1 mRNA=0.51 ±0.06, IUGR GLUT1 protein=0.56±0.09; p<0.05); in contrast, only GLUT4 protein was decreased (C=1.0, IUGR GLUT4 protein=0.35±0.08). GLUT4 mRNA was not significantly altered in IUGR male hearts. We conclude that GLUT1 mRNA and protein and GLUT4 protein are decreased in adult male IUGR cardiac muscle. These results are intriguing because of the increased mortality of coronary artery disease in adult males with syndrome X. Normal cardiac muscle responds to ischemia by increasing glucose oxidation (relative to fatty acid oxidation) to decrease subsequent oxygen consumption. We speculate the decreased GLUT expression may blunt this response and play a role in the mortality associated with syndrome X.
Kinetics of hydrolysis of cis-dichloro- and cis-chloroaquobis(propylenediamine)-chromium(III) cations

Abstract In 0·10 F HClO4, cis-Cr(pn)2Cl2+ has been found by spectrophotometric, Cl− release and chromatographic methods to aquate to the previously unreported species cis-Cr(pn)2(OH2)Cl2+; at 25·0°C the first-order constant is k1 = (3·5 ± 0·3) × 10−4 sec−1. At 25·0°C, cis-Cr(pn)2(OH2)Cl2+ hydrolyses in 3·1 F HClO4 with a pseudo first-order rate constant of k2 = (9·7) ± 0·9) × 10−6 sec−1, the product having been tentatively identified as a new complex, cis-Cr(pn)2(OH2)23+. Visible absorption spectra of the complexes are reported.
Sternal destruction in rheumatoid arthritis

In rheumatoid arthritis, erosive destruction of articular surfaces is a common finding. The diarthrodial joints primarily are involved and gross destruction of the amphiarthrodial joint of the manubriosternal area is rare.
Threshold estimation of ultrasound-induced lung hemorrhage in adult rabbits and comparison of thresholds in mice, rats, rabbits and pigs

Abstract The objective of this study was to assess the threshold and superthreshold behavior of ultrasound (US)-induced lung hemorrhage in adult rabbits to gain greater understanding about species dependency. A total of 99 76 ± 7.6-d-old 2.4 ± 0.14-kg New Zealand White rabbits were used. Exposure conditions were 5.6-MHz, 10-s exposure duration, 1-kHz PRF and 1.1-μs pulse duration. The in situ (at the pleural surface) peak rarefactional pressure, pr(in situ), ranged between 1.5 and 8.4 MPa, with nine acoustic US exposure groups plus a sham exposure group. Rabbits were assigned randomly to the 10 groups, each with 10 rabbits, except for one group that had nine rabbits. Rabbits were exposed bilaterally with the order of exposure (left then right lung, or right then left lung) and acoustic pressure both randomized. Individuals involved in animal handling, exposure and lesion scoring were blinded to the exposure condition. Probit regression analysis was used to examine the dependence of the lesion occurrence on in situ peak rarefactional pressure and order of exposure (first vs. second). Likewise, lesion depth and lesion root surface area were analyzed using Gaussian tobit regression analysis. Neither probability of a lesion nor lesion size measurements was found to be statistically dependent on the order of exposure after the effect of pr(in situ) was considered. Also, a significant correlation was not detected between the two exposed lung sides on the same rabbit in either lesion occurrence or size measures. The pr(in situ) threshold estimates (in MPa) were similar to each other across occurrence (3.54 ± 0.78), depth (3.36 ± 0.73) and surface area (3.43 ± 0.77) of lesions. Using the same experimental techniques and statistical approach, great consistency of thresholds was demonstrated across three species (mouse, rat and rabbit). Further, there were no differences in the biologic mechanism of injury induced by US and US-induced lesions were similar in morphology in all species and age groups studied. The extent of US-induced lung damage and the ability of the lung to heal led to the conclusion that, although US can produce lung damage at clinical levels, the degree of damage does not appear to be a significant medical problem. (E-mail: wdo@uiuc.edu )
Voltage flicker estimation based on linearization and L/sub p/ norms

This paper presents an approach to estimate voltage flicker components magnitudes and frequencies. The approach is based on L/sub p/ norms (p = 1, 2 and /spl infin/) and Taylor series linearization. Effects of sampling frequency, number of samples, time interval, and noise are introduced. The main result is that it is possible to design an L/sub p/ estimator to identify flicker frequency and amplitude from time series measurements.
Disease Prevention and Health Promotion in Urban Areas: CDC's Perspective

The mission of the Centers for Disease Control and Prevention (CDC) is to prevent disease, injury, and premature death and to promote quality of life. This mission applies to all Americans, especially to the poor and underserved. As so many people who are impoverished live in America's urban areas, the CDC has a unique and specific interest in the health problems of our urban population. The CDC has established five priorities: (1) strengthen essential public health services, (2) enrich capacity to respond to urgent threats to health, (3) develop a nationwide prevention network and program, (4) promote women's health, and (5) invest in our nation's youth. Each of these priorities will contribute to improving the health of people living in urban areas. The CDC has recently undertaken numerous initiatives to address health promotion and disease prevention issues in the urban setting. Future directions for the CDC lie in better understanding the role of socioeconomic and cultural factors in promoting health and how resources within urban areas can be used to promote health. The CDC needs to explore potential relationships with various types of partners. Solving urban health problems requires actions from many federal agencies as well as from state and local organizations.
Pathophysiology of Dysphagia and Aspiration

Swallowing is a complex action that requires the coordination of six cranial nerves, four cervical nerves, and more than 30 pairs of muscles. An understanding of the normal anatomy and physiology of the larynx, pharynx, esophagus, stomach, and intestine allows the clinician to better identify the mechanisms of dysphagia and aspiration, as well as synthesize compensatory strategies and preventative measures. This review summarizes the normal anatomy and physiology of deglutition, as well as several pathophysiological mechanisms of swallowing disorders. Dysphagia can be divided into neuromuscular, mechanical, and iatrogenic mechanisms. Etiologies of swallowing disorders and aspiration include neurogenic dysphagia, gastroesophageal reflux disease, Ludwig’s angina, retropharyngeal infections, Zenker’s diverticulum, non-oral enteral feedings, tracheal intubation and tracheostomy, general anesthesia, and head and neck cancer treatments.
SU‐GG‐J‐131: Immobilization Bed for Multi‐Modality Image Registration

Purpose: To construct an immobilization bed for mice that will allow for longitudinal multimodality imaging studies as well as conformai radiotherapy. The bed must be capable of both intra‐examination immobilization as well as inter‐examination positioning reproducibility. It must also accommodate mice of various sizes and facilitate image registration.Method and Materials: An immobilization bed was manufactured from clear acrylic to enable use with optical imaging modalities. Measurements of multiple mice of various ages and species were made in order to find the optimal size for the bed and for the restrainer pegs. The pegs were placed in stationary positions that effectively immobilize the majority of mice and enable high throughput imaging by avoiding adjustments for every mouse. The pegs were placed such that the front legs of the subject are each placed between two pegs as are the hind legs. An additional set of pegs were placed laterally and posteriorly to guide the hind legs in a reproducible direction. Na‐22 PET/CT fiducials were put into the pegs at unique depths to provide a three‐dimensional reference to allow fast and accurate image registration.Results: An average sized nude mouse without anesthesia (a worst case scenario test) was only capable of 3mm of movement vertically. Serial CT scans in‐between which the bed was moved showed no shifts in bony anatomy or external soft tissues. When PET and CT scans were registered without use of the fiducials, the heart was misplaced medially by ∼1mm and inferiorly by ∼1mm. The fiducials have allowed for accurate CT registration. Conclusion: The bed is effective in immobilization and image registration. The use of this bed will be enable the elucidation of minute changes in the PET scans and the use of molecular imaging data for radiation treatment planning and followup.
Raman Spectroscopic Observation of Laser-Induced Oxidation of Transition-Metal Borides, Carbides, and Nitrides:

Laser Raman microprobe examination in air of small-particle-sized (powders and whiskers) TiN, TiB2, TiC, WC, ZrN, and NbN revealed the formation of surface oxides, which were induced by laser heating. The rate of oxide formation varied with the particle size of the samples and the laser power density applied. The oxides produced were characterized by their Raman spectra. Thus, the Raman spectra obtained with a microprobe should always be carefully analyzed to ascertain whether oxidation or decomposition of so-called inert materials, especially in powder form, has occurred.
Large electron accelerators powered by intense relativistic electron beams

1407_52Novel techniques are described by which electromagnetic energy can be stored, compressed and then used to accelerate high current particle beams to high energy.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Cluster randomized trials to study the comparative effectiveness of therapeutics: stakeholders' concerns and recommendations.

Purpose To describe the concerns raised by health plan members, providers and purchasers related to studying the comparative effectiveness of therapeutics using cluster randomized trials (CRTs) within health plans. An additional goal was to develop recommendations for increasing acceptability. Methods Eighty-four qualitative in-depth telephone interviews were conducted; 50 with health plan members, 21 with providers, and 13 with purchasers. Interviews focused on stakeholders' concerns about and recommendations for conducting CRTs in health plans. Results Members expressed concerns that CRTs might compromise their healthcare. Providers and purchasers recognized the value of and the need for comparative effectiveness research. Providers expressed concerns that they would not have sufficient time to discuss a CRT with patients, and that participation in such a study could negatively impact their relationships with patients. Purchasers would want assurances that study participation would not result in members receiving lesser care, and that benefits would remain equitable for all members. Conclusions This study provides insight into how health plan members, providers and purchasers might react to a CRT being conducted in their health plan. The recommendations reported here provide guidance for researchers and policy makers considering this methodological approach and suggest that with sufficient preparation and planning CRTs can be an acceptable and efficient methodology for studying the comparative effectiveness of therapeutics in real world settings. Copyright © 2009 John Wiley & Sons, Ltd.