cssi/SciSciGPT-SciSciNet huggingface dataset:
Use of cine magnetic resonance angiography in quantifying aneurysm pulsatility associated with endoleak.

Abstract Objective Persistent aneurysm perfusion or endoleak is associated with pulsatility of abdominal aortic aneurysm (AAA) after endovascular repair. However, the resultant pulsatile change in aneurysm diameter may be difficult to quantify, and therefore its significance is unknown. In this study cine magnetic resonance angiography (MRA) was used to quantify aneurysm wall motion during the cardiac cycle and to correlate it with the presence and type of endoleak. Methods Cine MRA was performed in 16 patients undergoing endovascular repair of AAA. A 1.5 T magnet and post-processing with GEMS 4.0 Fiesta computerized video image analysis software were used to calculate maximum aortic diameter during systole and diastole. Changes in aortic diameter were determined from these measurements. Cine MRA was performed on aneurysms before treatment and in patients with and without endoleak after endovascular repair. Type of endoleak was confirmed at angiography in all cases. Four patients had antegrade (type I) endoleak, and eight patients had retrograde (type II) endoleak; no endoleak was present in four patients. Endovascular grafts with stent support throughout the entire length of the graft (Talent) were used in all cases (14 bifurcated grafts, 2 tube grafts). Results Cine MRA demonstrated significantly greater wall motion and resultant change in aneurysm diameter in patients with type I endoleak compared with patients without endoleak (type I, 2.14 ± 1.28 mm vs no endoleak, 0.12 ± 0.09 mm, P = .001). Change in aneurysm diameter in patients with type II endoleak was not significantly greater than in patients with no endoleak (type II, 0.26 ± 0.21 mm vs no endoleak, 0.12 ± 0.09 mm, P = NS). Untreated aneurysms demonstrated the greatest change in diameter during the cardiac cycle (3.51 ± 0.79 mm). Conclusion Cine MRA may be used to accurately quantify AAA wall motion before and after endovascular stent-graft treatment. The extent of change in diameter corresponds to the type of endoleak, with antegrade (type I) endoleak generating greater pulsatile change in diameter than retrograde-collateral (type II) endoleak or no endoleak. Cine MRA may provide a noninvasive means of assessing the success of endovascular treatment of AAA. Further studies will be necessary to confirm the utility and efficacy of cine MRA in postoperative assessment of endovascular aneurysm repair.
Mathematical and computational aspects of nonuniform frictional slip modeling

A mechanics-based model of non-uniform frictional sliding is studied from the mathematical/computational analysis point of view. This problem is of a key importance for a number of applications (particularly geomechanical ones), where materials interfaces undergo partial frictional sliding under compression and shear. We show that the problem is reduced to Dirichlet's problem for monotonic loading and to Riemman's problem for cyclic loading. The problem may look like a traditional crack interaction problem, however, it is confounded by the fact that locations of n sliding intervals are not known. They are to be determined from the condition for the stress intensity factors: K11=0 at the ends of the sliding zones. Computationally, it reduces to solving a system of 2n coupled non-linear algebraic equations involving singular integrals with unknown limits of integration.
ON THE THEORY OF STABILITY OF MOTION OF A NONLINEAR SYSTEM ON A TIME SCALE

We investigate the problem of stability of a nonlinear system on a time scale and propose a unified approach to the analysis of stability of motion based on a generalized direct Lyapunov method.
Prediction of RNA binding proteins comes of age from low resolution to high resolution

Networks of protein–RNA interactions is likely to be larger than protein–protein and protein–DNA interaction networks because RNA transcripts are encoded tens of times more than proteins (e.g. only 3% of human genome coded for proteins), have diverse function and localization, and are controlled by proteins from birth (transcription) to death (degradation). This massive network is evidenced by several recent experimental discoveries of large numbers of previously unknown RNA-binding proteins (RBPs). Meanwhile, more than 400 non-redundant protein–RNA complex structures (at 25% sequence identity or less) have been deposited into the protein databank. These sequences and structural resources for RBPs provide ample data for the development of computational techniques dedicated to RBP prediction, as experimentally determining RNA-binding functions is time-consuming and expensive. This review compares traditional machine-learning based approaches with emerging template-based methods at several levels of prediction resolution ranging from two-state binding/non-binding prediction, to binding residue prediction and protein–RNA complex structure prediction. The analysis indicates that the two approaches are complementary and their combinations may lead to further improvements.
Erosion in the DIII-D divertor by neon-detached plasmas

We report the first measurements of erosion of divertor materials by plasmas detached by neon injection. Neon injection cooled the plasma edge by radiation, reduced the temperature and increased the density of the divertor plasma, and reduced the peak heat flux onto the divertor plate, while maintaining good H-mode energy confinement and purity of core plasma. The rate of carbon erosion at the outer strike point was very high (∼15 nm/s), in contrast to the absence of erosion from plasmas detached by deuterium injection observed in previous experiments. The erosion rate for tungsten and vanadium remained low for neon-detached plasma. A likely cause of the high net carbon erosion rate is physical sputtering by neon, chemically enhanced by the formation of hydrocarbons.
Estuarine oxygen dynamics: What can we learn about hypoxia from long-time records in the Delaware Estuary?

Hypoxia and anoxia occurred in the upper Delaware Estuary throughout much of the 20th century and diminished over the past several decades. I reviewed 30 yr of data from my laboratory's research efforts, 40 yr of consistent monitoring data from a multistate agency, results from inconsistent data collection from the past century, and anecdotal information to construct a long-time picture of the decline and increase of dissolved oxygen concentrations (DO) in the urban region of the estuary. The primary cause of the DO decline appeared to be inputs or allochthonous materials from urban sources (reduced nitrogen and carbon). In spite of extremely high nutrient concentrations, excess algal production did not influence DO anywhere along the tidal freshwater stretch or the saline portion of the well-mixed Delaware Estuary; and it does not have an influence today. The nutrient loading to the Delaware Estuary is very high, yet the typical signs of eutrophication are not obvious. Based on a model of apparent oxygen utilization, the Delaware Bay apparently had higher primary production 50 yr ago, a time when nutrient concentrations were as high or higher than today, shellfish and finfish production were apparently also higher, and DO was close to saturation. This analysis is offered as guidance in assessing and managing estuarine eutrophication, which is too often considered narrowly to be the result of inadvertent overfertilization by nutrients or a single nutrient element.
Regulation of [3H]norepinephrine release from guinea pig hippocampus by σ2 receptors

Abstract The binding profile of the σ2 receptor ligand endo-N-(8-methyl-8-azabicyclo[3.2.1.]oct-3-yl)-2,3-dihydro-(1-methyl)ethyl-2-oxo-1H-benzimidazole-1-carboxamidehydrochloride (BIMU-8) had previously been determined, but its agonist/antagonist status at σ2 receptors had not been identified. We therefore investigated the effects of BIMU-8 for its ability to regulate the stimulated release of [3H]norepinephrine from slices of guinea pig hippocampus. BIMU-8 alone, at a concentration chosen to occupy 50% of σ2 receptors, had no significant effect on N-methyl- d -aspartate (NMDA)-stimulated release of [3H]norepinephrine. We have shown previously that the σ receptor agonist (+)-pentazocine inhibits NMDA-stimulated release in a concentration-dependent manner, producing a biphasic inhibition curve. Similarly, the σ receptor agonist 1S,2R-(−)-cis-N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)cyclohexylamine (BD737) produced a broad inhibition curve. The inhibition by low concentrations of (+)-pentazocine or BD737 that selectively activated σ1 receptors was reversed by the σ1-selective receptor antagonist (1-(cyclopropylmethyl)-4-2′-oxoethyl)piperidine HBr (DuP 734). In the current study, when the σ1 component of inhibition by (+)-pentazocine was blocked by DuP 734, the remaining component of inhibition mediated by σ2 receptors was reversed by BIMU-8. Our results suggest that (1) BIMU-8 is an antagonist at σ2 receptors and that (2) σ2 receptors contribute to regulation of norepinephrine release in guinea pig hippocampus.
The capacity ratio as a measure of solvency in experiential education.

Objective. To determine the utility of the capacity ratio to measure and compare solvency in experiential education in 6 colleges and schools of pharmacy in the Northwestern United States.Methods. ...
Denitrification in a nitrogen-limited stream ecosystem

Denitrification was measured in hyporheic, parafluvial, and bank sediments of Sycamore Creek, Arizona, a nitrogen-limited Sonoran Desert stream. We used three variations of the acetylene block technique to estimate denitrification rates, and compared these estimates to rates of nitrate production through nitrification. Subsurface sediments of Sycamore Creek are typically well-oxygenated, relatively low in nitrate, and low in organic carbon, and therefore are seemingly unlikely sites of denitrification. However, we found that denitrification potential (C & N amended, anaerobic incubations) was substantial, and even by our conservative estimates (unamended, oxic incubations and field chamber nitrous oxide accumulation), denitrification consumed 5–40% of nitrate produced by nitrification. We expected that denitrification would increase along hyporheic and parafluvial flowpaths as dissolved oxygen declined and nitrate increased. To the contrary, we found that denitrification was generally highest at the upstream ends of subsurface flowpaths where surface water had just entered the subsurface zone. This suggests that denitrifiers may be dependent on the import of surface-derived organic matter, resulting in highest denitrification rate at locations of surface-subsurface hydrologic exchange. Laboratory experiments showed that denitrification in Sycamore Creek sediments was primarily nitrogen limited and secondarily carbon limited, and was temperature dependent. Overall, the quantity of nitrate removed from the Sycamore Creek ecosystem via denitrification is significant given the nitrogen-limited status of this stream.
The Scope of Coverage of the Truth in Lending Act

Although the Truth in Lending Act (TIL) was actively considered by Congress for the better part of a decade questions of coverage rarely arose, and debate on the scope of the coverage provisions was almost nonexistent. The reasons appear to be twofold. First, as Justice Frankfurter observed, every statute has a “core of indisputable application” about which there is little question, and there was general agreement that certain types of transactions constituting the majority of consumer credit transactions would clearly be covered. Thus the undisputed coverage of the TIL Act was very broad. Second, legislators were preoccupied with debating a number of the substantive provisions that creditors found so objectionable and consumerists thought so necessary that little attention was focused on defining the perimeter of coverage. Moreover, as this paper will show, a number of “fringe” transactions bear at least superficial resemblance to transactions that were clearly to be covered. Thus, creditors might wisely have preferred to take their chances on later interpretations of the scope of coverage by administrators and courts rather than risking a specific congressional resolution. of the coverage issues.
Contribution to the mathematical theory of mass behavior: I. The propagation of single acts

The propagation of a single act in a large population is supposed to depend on some external circumstance and on an “imitation component”, where encounters with individuals who are performing or have already performed the act contribute to the tendency of an individual to perform it. The “tendency” to perform is supposed to be measured by the average frequency of stimuli, randomly distributed in time, impinging on the individual. The deduced equation is a relation between the fraction of the population who have performed the act and time, provided the time course of the “external circumstance” and the way in which the imitation component contributes are known. Several special cases are studied, in particular, cases without the imitation component, cases with imitation only, and various mixed cases. Examples are given of social situations in which such factors may operate and general suggestions are made for the systematization of observations and/or experiments to test the assumptions of the theory.
Estimating time-since-death from the free amino acid content of the mollusc shell; a measure of time averaging in modern death assemblages? Description of the technique

The concentration of free amino acids (FAA) increases in three species of bivalves, Tagelus plebeius, Rangia cuneata, and Phacoides pectinatus, taken from ever increasing depth in the upper 72 cm of a core from a mesohaline, sandy-bottom site in Copano Bay, Texas. Analysis of museum shells of known age indicates that [FAA]* increases with shell age (time-since-death) as the proteinaceous matrix gradually breaks down. Estimation of relative age (one shell older than another) in shells less than a few hundred years old is readily accomplished using a measure of [FAA]. The estimation of absolute age (actual time-since-death) depends on an independent calibration. Museum shells of known age offer one possible method. The glycinelalanine ratio decreases with time either because the rate of alanine production increases or because glycine diffuses out of shells more rapidly. Hence [glycine] is a useful estimator of age for relatively young shells and [alanine] or [glutamic acid] for older shells. Age estimates from calibration curves using museum specimens of T. plebeius and R. cuneata and independent estimates based on sediment accumulation rates agree for shells taken from the Copano Bay site. Measuring [FAA] provides a method to appraise the degree of time averaging in modern death assemblages because the relationship of shell age and burial depth can be determined. [FAA] changed little in shells below 72 cm in the core indicating that an increase in time averaging may have occurred below that depth, whereas, in the upper 72 cm, changes in death assemblage
Utilization of chemical looping strategy in coal gasification processes

Abstract Three chemical looping gasification processes, i.e. Syngas Chemical Looping (SCL) process, Coal Direct Chemical Looping (CDCL) process, and Calcium Looping process (CLP), are being developed at the Ohio State University (OSU). These processes utilize simple reaction schemes to convert carbonaceous fuels into products such as hydrogen, electricity, and synthetic fuels through the transformation of a highly reactive, highly recyclable chemical intermediate. In this paper, these novel chemical looping gasification processes are described and their advantages and potential challenges for commercialization are discussed.
Ventricular septal summit stimulation in atrioventricular nodal reentrant tachycardia

Abstract In all, 18 consecutive patients with atrioventricular nodal reentry tachycardia (AVNRT) underwent right ventricular (RV) stimulation during AVNRT from either the RV apex or summit. Stimulation from the RV apex advanced the tachycardia with the same atrial sequence in 6 of 18 patients (33%), but never conclusively excluded the presence of a low atrial tachycardia. RV summit stimulation resulted in direct stimulation of the tow septal right atrium in 6 patients. RV summit stimulation advanced the tachycardia in 4 patients, delayed it in 2 and terminated it in 3 without an atrial electrogram. The latter 2 findings exclude the presence of a low atrial tachycardia. Thus, in patients with AVNRT, application of extrastimuli closer to the putative reentrant site enables greater efficacy in tachycardia resetting and in excluding a low septal atrial tachycardia.
A13. Dermocosmoceuticals after ablative and non-ablative laser and IPL photorejuvenation

During recent years, requests for treatment of photoinduced damage such as wrinkles, atrophy, telangiectasia, dyschromia and enlarged pores have increased considerably. In response to the increase in demand, various techniques have been developed that use light sources that are coherent (laser), or non-coherent (IPL), or other techniques, such as radio frequencies. Demand is also increasing for treatments for slight blemishes using non-invasive methods, with a post-operative course that does not affect the patient's normal working and/or recreational activities. We discuss the possibilities and limits that these procedures present.
Identifying Red Flags: Using Anthropometry Measures to Screen for Elevated Blood Pressure Risk in Children

Childhood obesity is predictive of adulthood obesity, hypertension, and cardiovascular disease risk. The purpose of this study was to examine BMI for age as an independent risk factor for elevated ...
Parasite effects on isopod feeding rates can alter the host’s functional role in a natural stream ecosystem

Changes to host behaviour as a consequence of infection are common in many parasite-host associations, but their effects on the functional role hosts play within ecosystems are rarely quantified. This study reports that helminth parasites significantly decrease consumption of detritus by their isopod hosts in laboratory experiments. Natural host and parasite densities across eight contiguous seasons were used to estimate effects on the amount of stream detritus-energy processed. Extrapolations using mass-specific processing rates from laboratory results to field patterns suggest that the effects of the parasites occur year round but the greatest impact on the amount of detritus processed by isopods occurs in the autumn when the bulk of leaf detritus enters the stream, and when parasite prevalence in the isopod population is high. Parasites have a lesser impact on the amount of detritus processed in spring and summer when isopods are most abundant, when parasite prevalence is not high, and when fish predation on isopods is high. These results support the idea that parasites can affect the availability of resources critical to other species by altering behaviours related to the functional role hosts play in ecosystems, and suggest that seasonality may be an important factor to consider in the dynamics of these parasite-host interactions.
A new framework for computationally efficient structure–structure evolution linkages to facilitate high-fidelity scale bridging in multi-scale materials models

Abstract A novel mathematical framework called materials knowledge systems (MKS) was recently formulated to extract, store and recall computationally efficient hierarchical linkages that are at the core of multi-scale modeling of materials phenomena. A salient feature of this new framework is that it facilitates flow of high-fidelity information in both directions between the constituent length scales, and thereby offers a new strategy for concurrent multi-scale modeling. The viability of this new framework has thus far been largely explored for capturing the mechanical response of composite material systems. This paper extends the MKS framework to applications involving microstructure evolution, where the local states are typically defined in a continuous local state space. In particular, it will be shown that it is possible to obtain an efficient discretization of the local state space to produce a sufficiently accurate description of the linearized structure–structure evolution linkages for modeling spinodal decomposition. Furthermore, it will be shown that these linkages can be used successfully to accurately predict the continuous evolution of microstructure over the long time periods involved in such problems.
Transaction costs and the transition to environmentally sustainable development

As global environmental problems mount, the transition to sustainable economic development seems elusive. A major reason is that the world is facing a monumental challenge in overcoming policy, market and institutional failures. The most formidable barriers are institutional rigidities and transaction costs that replicate the same patterns of resource-based development, despite the rising costs associated with increasing environmental degradation. Vested interests reinforce this institutional intransigence. Reorienting economies to foster more sustainable development will only succeed if we overcome these institutional barriers and costs.
v-Bundle: Flexible Group Resource Offerings in Clouds

Traditional Infrastructure-as-a-Service offerings provide customers with large numbers of fixed-size virtual machine (VM) instances with resource allocations that are designed to meet application demands. With application demands varying over time, cloud providers gain efficiencies through resource consolidation and over-commitment. For cloud customers, however, this leads to inefficient use of the cloud resources they have purchased. To address cloud customers' dynamic application requirements, we present a new cloud resource offering, called v-Bundle, which makes flexible the exchange of resource capacity among multiple VM instances belonging to the same customer. Specifically targeting network resources, for each customer application, we first use DHT-based techniques to achieve an initial VM placement that minimizes its use of the data center network's bi-section bandwidth. When VMs' networking requirements change, the customer can then use v-Bundle to trade the networking resources allocated to her application. v-Bundle maintains information about network resources with any-cast tree-based methods implemented as extensions of the Pastry pub-sub core. Experimental evaluations show that the approach can scale well to thousands of hosts and VMs, and that v-Bundle can provide customers with better bandwidth utilization and improved application quality of service through borrowing extra bandwidth when needed, at no additional cost in terms of the total resources allocated to the customer.
Behavioral exchanges between teachers and children over the course of a typical preschool day: Testing bidirectional associations

In the present study, 314 preschool classrooms and 606 children were observed to understand the behavioral exchanges between teachers and children. Teachers' emotionally and organizationally supportive behaviors and children's engagement were explored for longitudinal associations throughout a day. Observations were conducted in each classroom wherein emotional and organizational supports were assessed, followed by observations of two children's positive engagement with teachers, tasks, and peers as well as negative classroom engagement. Cross-lagged autoregressive models were used to test for time-lagged associations which could be unidirectional or bidirectional. Results indicated teachers' emotionally and organizationally supportive behaviors were related to later child engagement in seven of eight models. Furthermore, in two of those seven models, we found evidence of bidirectional associations whereby children's engagement was associated with later teacher emotional and organizational supports. Findings are discussed in terms of understanding classroom processes over the course of a day in preschool.
Thionapthene-2-carboxylic acid: a new antihypercalcemic agent.

Thiophene-2-carboxylic acid (TCA) was previously shown to be hypocalcemic in the rat. We have compared TCA with thionapthene-2-carboxylic acid (TNCA), an analog which is a more potent inhibitor of bone resorption in vitro, for the ability to decrease serum calcium concentration in vivo. In normocalcemic rats on a low calcium diet, TNCA (2 mmol/kg) produced a larger and more prolonged decrease in calcium concentration than TCA. In rats bearing the Walker 256 carcinosarcoma, which became hypercalcemic, TNCA produced a doserelated decrease in serum calcium concentration at 0.3–1.2 mmol/kg. TNCA reduced serum calcium concentration in 4–6 h, and the effects were sustained for up to 72 h. TNCA was effective after oral as well as sc administration. Unlike calcitonin which produced only a transient reduction in serum calcium followed by escape, the effects of TNCA (0.6 mmol/kg) were sustained for 1 week and were accompanied by a decrease in mortality in tumor-bearing animals. We conclude that TNCA is a potent hyp...
Urban Adolescents’ Understandings of the Relationship Between Background and Success

This qualitative study examined urban adolescents’ beliefs about how their backgrounds—“where they come from”—might influence their chances for success in the world of work. Participants were 27 adolescents participating in a school-to-work program or otherwise employed. To elicit their more experience-near ideas about the relationship between background and success, we attempted to thwart the adolescents’ tendency to voice the dominant ideology of individualism and achievement by asking not if but how background might matter. Four ways of viewing the relationship between background and success emerged from our inductive analysis. Results are discussed in terms of the adolescents’ abilities to hold multidimensional beliefs about success and economic status.
On-Road Evaluation of Inspection/Maintenance Effectiveness

This study presents an evaluation of inspection and maintenance (I/M) programs in terms of their effect on motor vehicle carbon monoxide (CO) and hydrocarbon (HC) exhaust emissions as measured on-road by remote sensing technology. The results show that the performance of past I/M programs at several monitored locations has been less effective than predicted by the U.S. Environmental Protection Agency. The emissions from I/M and non-I/M vehicles measured in Tucson, AZ, and in rural Colorado show no statistically significant difference. An apparent I/M effect observed in El Paso, TX, and in Denver, CO, is smaller than predicted. Comparisons of CO emissions by vehicle age for several years at the same locations in Chicago and Denver show no evidence that the Chicago centralized I/M program was more effective than the Denver decentralized I/M program.
The Relationship Between Faculty Unionism and Organizational Effectiveness

In a study of colleges and universities, unionized institutions are found to be less effective than nonunionized institutions on eight of nine dimensions of effectiveness. Statistically significant...
Novel CD measurement and precise pattern size extraction method for optical images

A new method for accurate CD measurement and precise pattern size extraction from optical images is proposed. The approach is based on the underlying field theory of optical image generation. The method demonstrates superior precision compared with traditional edge detection schemes based on the image and not on the field nature of image creation. The proposed method presents accuracy parallel to that achieved by SEM imaging. Therefore it provides an alternative to electronic microscopy measurements in certain cases. This new method may be implemented for applications of accurate mask-CD measurement, as well as for retrieving the mask model from an optical image for a die to model application.
GROUND STATE OF THE CHARGED BOSE GAS

The ground-state energy of the charged Bose gas is calculated by the pair-correlation variational method of Girardeau and Arnowitt. The method is exact in the high-density limit (${r}_{s}\ensuremath{\ll}1$) and provides a variational extrapolation to intermediate densities. The leading terms of the high-density expansion, obtained by iteration of the variational integral equation, are ${u}_{0}=\ensuremath{-}0.804{{r}_{s}}^{\ensuremath{-}\frac{3}{4}}\ensuremath{-}(\frac{1}{8})\mathrm{ln}{r}_{s}+O(1)$, where ${u}_{0}$ is the ground-state energy per particle in Rydbergs and ${r}_{s}$ is the ratio of the mean interparticle spacing to the Bohr radius. The first term was obtained previously by Foldy, but the logarithmic term is new; it is related to screening of the long-range correlations at a distance ${r}_{0}\ensuremath{\sim}{{r}_{s}}^{\ensuremath{-}\frac{1}{2}}{\ensuremath{\rho}}^{\ensuremath{-}\frac{1}{3}}$, in analogy with the logarithmic term in the correlation energy of the electron gas. Results of numerical solutions for the intermediate-density region are presented, ranging up to ${r}_{s}=10$. On the basis of a comparison with the energy calculated from the known low-density expansion, it is estimated that the transition into Wigner's electron crystal (here a boson crystal) should occur at ${r}_{s}\ensuremath{\sim}5$.
Physical map of defective interfering particles of bacteriophage f1.

Multiple passages of bacteriophage f1 at high multiplicities of infection lead to the accumulation of mutants that overgrow the wild-type phage in a mixed infection but are unable to complete an infectious cycle by themselves. These mutants (defective interfering particles) lack more than 70% of the genome and contain no intact rans-acting cistrons. Genetic and physical mapping of several defectives shows that they contain the origin of phage DNA replication and the large intercistronic space that surrounds this region. A marked selective advantage is given to some of these mutants by a partial duplication in this region of the genome.
On the stability of TiN-based electrocatalysts for fuel cell applications

Abstract The transition metal compound – titanium nitride (TiN), with its high electrical conductivity and corrosion resistance, can be a potential fuel cell material, particularly in the development of durable electrocatalysts replacing the state-of-the-art Pt/C. Compared to conventional carbon black, TiN nanoparticle (TiN NP) catalyst supports have a lower rate of corrosion under fuel cell conditions. The current research is a follow up study on the stability of TiN based fuel cell electrodes and its impact on the electrochemical activity of the Pt based electrocatalysts when used as an alternative to the state-of-the-art carbon black support in commercial fuel cell catalyst systems under fuel cell operating conditions. Through this paper, we report that an active behavior of TiN NP can be observed at the optimal conditions of 0.5 M H2SO4 and 60 °C. But under increased temperature or acidic conditions, the native layer on TiN tends to dissolve in the electrolyte exposing the underlying nitride surface which then gets passivated with hydroxide groups. Electrochemical and XPS characterization is used to validate our hypothesis of active or passive nature of TiN NP due to presence or absence of surface passivating -OH groups, respectively. The synthesized Pt/TiN electrocatalyst, upon subjecting to accelerated durability test, showed the performance trends which agree well with the active and passive nature of the TiN NP supports.
Acyclic Orientations of Random Graphs

An acyclic orientation of an undirected graph is an orientation of its edges such that the resulting directed graph contains no cycles. The random graphG"n","pis a probability space consisting of subgraphs ofK"nthat are obtained by selecting eachK"n-edge with independent probabilityp. The random graphQ^n"2","pis defined analogously and consists of subgraphs of then-cube,Q^n"2. In this paper we first derive a bijection between certain equivalence classes of permutations and acyclic orientations. Second, we present a lower and an upper bound on the r.v.a(G"n","p) that counts the number of acyclic orientations ofG"n","p. Finally we study the distribution ofa(G"n","p) anda(Q^n"2","p) and show that log"2a(G"n","p) and log"2a(Q^n"2","p) are sharply concentrated at their respective expectation values.
Melting and sintering of a body-centered cubic superlattice of PbSe nanocrystals followed by small angle X-ray scattering

The structural evolution of a body-centered cubic (bcc) superlattice of 6.6 nm diameter organic ligand-coated PbSe nanocrystals was studied in situ by small-angle X-ray scattering (SAXS) as it was heated in air from room temperature to 350 °C. As it was heated above room temperature, the superlattice contracted slightly but maintained bcc structure up to 110 °C. Once the temperature rose above 110 °C, the superlattice began to disorder, by first losing long-range translational order and then local positional order. At temperatures exceeding 168 °C, the nanocrystals sintered and oxidized, transforming into PbSeO3 nanorods.
Pharmacokinetics and pharmacodynamics of phase II drug metabolizing/antioxidant enzymes gene response by anticancer agent sulforaphane in rat lymphocytes.

This study assesses the pharmacokinetics (PK) and pharmacodynamics (PD) of Nrf2-mediated increased expression of phase II drug metabolizing enzymes (DME) and antioxidant enzymes which represents an important component of cancer chemoprevention in rat lymphocytes following intravenous (iv) administration of an anticancer phytochemical sulforaphane (SFN). SFN was administered intravenously to four groups of male Sprague–Dawley JVC rats each group comprising four animals. Blood samples were drawn at selected time points. Plasma were obtained from half of each of the blood samples and analyzed using a validated LC–MS/MS method. Lymphocytes were collected from the remaining blood samples using Ficoll-Paque Plus centrifuge medium. Lymphocyte RNAs were extracted and converted to cDNA, quantitative real-time PCR analyses were performed, and fold changes were calculated against those at time zero for the relative expression of Nrf2-target genes of phase II DME/antioxidant enzymes. PK–PD modeling was conducted base...
A new secular equation for slip waves along the interface of two dissimilar anisotropic elastic half-spaces in sliding contact

Abstract We consider wave propagation along the interface of two dissimilar anisotropic elastic half-spaces that are in sliding contact. A new secular equation is obtained that covers all special cases in one equation. One special case is when a Rayleigh wave (called the R -wave) can propagate in both half-spaces with the same wave speed. Another special case is when a slip wave (called the S -wave) can propagate in each of the half-spaces with the same wave speed. If a Rayleigh wave and a slip wave can propagate in one of the half-spaces it is called the RS-wave. In this case an interfacial slip wave exists in which the other half-space is at rest unless an RS-wave can also propagate in the other half-space. The results for general anisotropic elastic materials are applied to orthotropic materials.
An Objective Analysis Technique for Constructing Three-Dimensional Urban-Scale Wind Fields

An objective analysis procedure for generating mass-consistent, urban-scale three-dimensional wind fields is presented together with a comparison against existing techniques. The algorithm employs terrain following coordinates and variable vertical grid spacing. Initial estimates of the velocity field are developed by interpolating surface and upper level wind measurements. A local terrain adjustment technique, involving solution of the Poisson equation, is used to establish the horizontal components of the surface field. Vertical velocities are developed from successive solutions of the continuity equation followed by an iterative procedure which reduces anomalous divergence in the complete field. Major advantages of the procedure are that it is computationally efficient and allows boundary values to adjust in response to changes in the interior flow. The method has been successfully tested using field measurements and problems with known analytic solutions.
Legionella pneumophila Entry Gene rtxA Is Involved in Virulence

Successful parasitism of host cells by intracellular pathogens involves adherence, entry, survival, intracellular replication, and cell-to-cell spread. Our laboratory has been examining the role of early events, adherence and entry, in the pathogenesis of the facultative intracellular pathogen Legionella pneumophila. Currently, the mechanisms used by L. pneumophila to gain access to the intracellular environment are not well understood. We have recently isolated three loci, designated enh1, enh2, and enh3, that are involved in the ability of L. pneumophila to enter host cells. One of the genes present in the enh1 locus, rtxA, is homologous to repeats in structural toxin genes (RTX) found in many bacterial pathogens. RTX proteins from other bacterial species are commonly cytotoxic, and some of them have been shown to bind to β2 integrin receptors. In the current study, we demonstrate that the L. pneumophila rtxA gene is involved in adherence, cytotoxicity, and pore formation in addition to its role in entry. Furthermore, an rtxA mutant does not replicate as well as wild-type L. pneumophila in monocytes and is less virulent in mice. Thus, we conclude that the entry gene rtxA is an important virulence determinant in L. pneumophila and is likely to be critical for the production of Legionnaires' disease in humans.
A neural network model of serial order recall from short-term memory

The authors present a neural network that converts a spatial pattern encoding the serial order of a list of items into a corresponding sequence of output events. Performance can be initiated, interrupted, and continued under control of a single, independent signal. The network uses recurrent connections to normalize and store node activity in short-term memory, to choose the items in sequence, and to modulate the output rate during readout. The latency and duration of output events can model certain empirical trends of human performance in recalling lists of items. >
Coagulopathy with the use of hetastarch in the treatment of vasospasm

The use of colloid agents to achieve hypervolemia in the prevention and treatment of postsubarachnoid hemorrhage (post-SAH) vasospasm is included in the standard of care at many institutions. Risk profiles are necessary to ensure appropriate use of these agents. In a series of 85 patients with recent aneurysmal SAH, 26 developed clinical symptoms of vasospasm. Fourteen of the 26 were treated with hetastarch for volume expansion while the other 12 received plasma protein fraction (PPF). Clinically significant bleeding pathologies were noted in six patients who received hetastarch as a continuous intravenous infusion. Hetastarch increased partial thromboplastin time from a mean of 23.9 seconds to a mean of 33.1 seconds (p < 0.001) in all patients who received infusions of this agent, while no effect was noted in the 12 patients who received PPF infusions. No other coagulation parameters were altered. This study shows an increase in coagulopathy with the use of hetastarch as compared with the use of PPF for the treatment of postaneurysmal vasospasm.
THE EFFECTS OF INTERACTION ON SPOKEN DISCOURSE

Near-term spoken language systems will likely be limited in their interactive capabilities. To design them, we shall need to model how the presence or absence of speaker interaction influences spoken discourse patterns in different types of tasks. In this research, a comprehensive examination is provided of the discourse structure and performance efficiency of both interactive and noninteractive spontaneous speech in a seriated assembly task. More specifically, telephone dialogues and audiotape monologues are compared, which represent opposites in terms of the opportunity for confirmation feedback and clarification subdialogues. Keyboard communication patterns, upon which most natural language heuristics and algorithms have been based, also are contrasted with patterns observed in the two speech modalities. Finally, implications are discussed for the design of near-term limited-interaction spoken language systems.
Stability over time of hematological variables in 197 children with sickle cell anemia

One hundred ninety-seven children with sickle cell anemia were followed for 4 years at the Wayne State Comprehensive Sickle Cell Center to evaluate the stability of the hematological variables (Hb, Hct, RBC count, MCV, %HbF and %HBA2) over time. The mean values of the hematological measurements taken during three separate 16-month intervals were used to represent an individual's values. The correlations of the hematological variables between intervals ranged from a low of 0.46 for %HBA2 to a high of 0.91 for %HbF. Correlations that spanned two intervals (an average of 32 months) were of the same magnitude as those that spanned only one interval (an average of 16 months), suggesting that there was no decrease in the degree of stability of these variables as the time between measurements increased. The stability of the correlations between variables within intervals, and the stability of the coefficients of the first two principal components of the six hematological variables over time suggested that the relationships among variables were also stable. In a recent report [Odenheimer et al, 1983], we used the values of the six hematological variables collected at an individual's first visit to the sickle cell center to identify four hematologically distinct subgroups of children. In the current report, we found that as many as 83% of the individuals remained in the same subgroup in at least two of the three follow-up intervals, suggesting that the factors that contributed to this classification were the result of stable, rather than transient phenomena.
Molecular characterization and diversity of thermophilic iron-reducing enrichment cultures from deep subsurface environments.

J. ZHOU, S. LIU, B. XIA, C. ZHANG, A.V. PALUMBO AND T.J. PHELPS. 2001. Aims: The objectives of this work were to explore the diversity in Fe (III)-reducing enrichment cultures from the deep subsurface and to identify strains involved in metal reduction. Methods and Results: Analyses of 16S ribosomal RNA (rRNA) of enrichments, supplemented with hydrogen, acetate or pyruvate as an electron donor, identified three dominant operational taxonomic units (OTUs). All cultures exhibited considerable diversity (36–24 OTUs), even after being transferred at least nine times. Two OTUs were present in all three cultures, constituting about 65% of the total clones examined. Conclusions: Dominant OTUs appeared to be most closely related to Thermoanaerobacter ethanolicus or T. kivui. One OTU, which is potentially responsible for autotrophic Fe (III) reduction, was only about 95% similar to T. ethanolicus and may represent a new species. Significance and Impact of the Study: An unexpectedly high diversity was found in these enrichments and this diversity may be a feature that can be exploited.
Locomotor Mimicry in Butterflies? A Critical Review of the Evidence

The hypothesis of locomotor mimicry in butterflies presented by Srygley ( Phil. Trans. R. Soc. Lond. B 343, 145—155 (1994)) is criticized as unparsimonious, from two perspectives. First, the existence of mimicry between palatable but unprofitable prey is disputed on theoretical and empirical grounds. The lack of a strong predator aversion stimulus seriously undermines the unprofitable prey scenario, and supposed cases of mimicry of unprofitable models are explicable by traditional mimetic modes. Second, correlations of phenotypic characters used to support alternative adaptive peaks for palatable and unpalatable butterflies are criticized for failing to account for phylogenetic relationships. Virtually all of the relevant variation in flight-related morphology is shown to be due to differences between clades, rather than mimicry groups. An alternative hypothesis emphasizing phylogenetic constraint in the evolution of morphological characters associated with predator avoidance is proposed. The ground rule — or perhaps doctrine would be a better term — is that adaptation is a special and onerous concept that should be used only where it is really necessary. When it must be recognized, it should be attributed to no higher a level of organization than is demanded by the evidence. In explaining adaptation, one should assume the adequacy of the simplest form of natural selection, that of alternate alleles in Mendelian populations, unless the evidence clearly shows that this theory does not suffice. G. C. Williams (1966, pp. 4—5).
A “Jekyll and Hyde” Within Aggressive Versus Friendly Interactions in REM and Non-REM Dreams

We hypothesized that representations of social interactions in REM and non-REM (NREM) dreams would reflect differing regional brain activation patterns associated with the two sleep states, and that levels of aggressive interactions would be higher in REM than in NREM dreams. One hundred REM, 100 NREM, and 100 wake reports were collected in the home from 8 men and 7 women using the Nightcap sleep-wake mentation-monitoring system and scored for number and variety of social interactions. We found that (a) social interactions were more likely to be depicted in dream than in wake reports, (b) aggressive social interactions were more characteristic of REM than NREM or wake reports, and (c) dreamer-initiated friendliness was more characteristic of NREM than REM reports. We conclude that processing of, or simulations about, selected social interactions is preferentially performed while "off-line" during the dream state, with the REM state specializing in simulation of aggressive interactions and the NREM state specializing in simulation of friendly interactions.
Flowfield Measurements in a Ribbed Channel Relevant to Internal Turbine Blade Cooling

The internal cooling of turbine blades is an important part of overall blade cooling that is necessary to survive current turbine inlet temperatures. This internal cooling is often performed by means of rib-turbulated passages designed to provide maximum heat transfer coefficients. One determining factor in the cooling effectiveness is the flow pattern created by the ribbed channel. This paper presents a comparison of the effect of two different channel blockage ratios on the fully developed flow pattern in a stationary ribbed channel. For the experimental investigation, a scaled-up ribbed passage was tested using of a closed-loop channel facility. The facility included a passage consisting of a developing region, a fully developed region, a 180° bend, and a second developing region following the bend. Friction factors were determined through the use of pressure taps throughout the channel, and flow fields were measured using a two-component laser Doppler velocimeter. A majority of the testing performed was done under conditions of in-line (i.e. non-staggered) ribs with ratios of rib height to channel hydraulic diameter of 0.10 and 0.17. All LDV measurements were performed at a Reynolds number of 20,000. Results indicate that both blockage ratios create significant recirculation regions immediately before and immediately following the rib. While the smaller rib results indicate a reattachment downstream of the rib, the larger rib results indicate that the flow is separated along the entire streamwise distance between the ribs. The smaller blockage ratio also indicated a small recirculation region directly on top of the rib, whereas the larger blockage ratio showed no such region. Additionally, the increased friction factor created by the larger ribs can be attributed to the larger recirculation regions between ribs.Copyright © 2004 by ASME