cssi/SciSciGPT-SciSciNet huggingface dataset:
Diffusion of reacting epoxy and amine monomers in polysulfone: a diffusivity model

Abstract In this work, a diffusivity model based on free volume theory is presented for the simultaneous diffusion of diglycidyl ether of bisphenol A (DGEBA) epoxy and bis( p -aminocyclohexyl) methane (PACM 20) amine monomers into amorphous polysulfone (PSU). This model is expected to predict and explain the diffusion behavior of the epoxy and amine monomers into PSU during the initial time periods. The overall free volume of the polymer system is estimated using a Kelley–Bueche approximation for free volume in a binary mixture consisting of a non-reacting thermoplastic and the reacting thermoset. The fractional free volume of the thermoset is estimated by the DiBenedetto equation. The model is valid only for low epoxy–amine concentrations and degrees of cure. The diffusivity model developed here suggests that reaction reduces the species diffusivity with increasing cure from a loss of the overall fractional free volume for diffusion. Further, a model for increased epoxy diffusivity from amine-induced PSU swelling is presented and validated using data from previous studies on the single-component diffusion of epoxy into amine-swollen PSU. By combining the reaction and swelling terms with the Arrhenius epoxy diffusivity, the epoxy diffusivity expression during the simultaneous diffusion and reaction of epoxy and amine into PSU for small times, is determined. Parametric studies on the nature of diffusivity are performed to determine the influence of the various free volume parameters on thermoset diffusion, and these studies show that the thermoset diffusivity, in general, decreases with time from reaction.
Development of a CTD biotag: Challenges and pitfalls

Abstract This paper describes the design and development of a small CTD biotag that measures a suite of oceanographic data. Though presently configured to measure conductivity, temperature, and depth along with geo-location, it is expandable to acquire behaviorally related data, including acceleration, ambient light, and compass heading. The size of the instrument (100 mm x 40 mm x 20 mm) has been optimized for deployments on medium-sized marine predators such as penguins, tuna, and sharks. Several first generation prototypes have been constructed and initial laboratory and field tests have been performed and are reported. In addition, this paper highlights the challenges and difficulties encountered during the developmental process of a new biologging instrument.
Antimicrobial Activity of the Macrolides Forocidins and Isomycins

Abstract Antimicrobial evaluation of the macrolides forocidins and isomycins in general, show diminished antimicrobial activity when compared to spiramycin. Interestingly, albeit minimal activity, the forocidins and isomycins exhibit some level activity against the opportunistic pathogens C. albicans and M. intracellulare, where the parent compound, spiramycin shows no notable activity.
Prediction of Heat Transfer from Burned Gas in Transitional Flow Inside a Tube

ABSTRACT The direct coupling of a thermally stabilized combustor and a steam generator has previously been shown by Strenger and Churchill to result in minimal concentrations of NO and CO and exceptionally high rates of heat transfer relative to conventional processes. Across the flame front, the Reynolds number falls from above to below 2100, leading to decaying turbulence and laminarization in the stream of hot burned gas. In the heat exchanger the cooling increases the Reynolds number and results in a sudden transition back to turbulent flow. The development and transition in the flow as well as the confinement are responsible for the high rates of heat transfer. The k-ϵ model has been adapted successfully to predict this complex behavior by using a controlled perturbation to trigger the transition at the experimentally observed point. The predictions not only agree well with experimental measurements of heat transfer but also provide insight into the fluid-mechanical and thermal behavior.
Descriptive epidemiology of genitourinary cancers

The American Cancer Society estimates that, in 1993, genitourinary (GU) cancers will account for about 37% of all new cases of cancer in men and about 4% in women. Approximately 18% of all cancer deaths in men and 3% in women will be from GU cancers. Identifying the differences in the occurrence of testicular, prostate, bladder, and renal cancer by age, race, sex, and geographic distribution and looking at trends over time are necessary for the development of etiologic hypotheses and appropriate health services.
Visual Sociology: Expanding Sociological Vision

This article is an overview of the contributions of photography to sociology and a discussion of potential uses of photography in sociological research. Visual sociology, after contributing to several studies in the early decades of American sociology, disappeared to reemerge during the 1960s. In the meantime, the use of visual methods in ethnographic description, the study of social processes in the laboratory, in studies of social change, as a key to interviewing grounded in the perspective of the subject and as a means through which phenomenological sociology may be constructed and communicated. Visual sociology, with increasing organizational success and emerging electronic aids, appears to be on the verge of greater recognition and use within mainstream sociology.
Transport and Retention Mechanisms of Colloids in Partially Saturated Porous Media

The transport, retention, and release of hydrophobic and hydrophilic polystyrene latex microsphere colloids were examined in 0.5-cm-thick, 26-cm-long slab chambers filled with either regular (hydrophilic) or weakly water-repellent sand. The water-repellent sand consisted of a mixture of 0.4% strongly water-repellent grains with unmodified regular sand for the remainder. The concentration of colloids in the outflow water was measured at the same time as the pore-scale distribution of colloids was recorded in still and video images. Although the type of sand affected the flow pattern in the top of the chamber, it did not affect the breakthrough for the same type of colloids. More hydrophilic colloids were eluted in the drainage water than hydrophobic colloids. Images showed that there was a greater retention of the hydrophobic colloids due to strongly attractive hydrophobic interaction forces between colloids and subsequent filtering of colloidal aggregates in the narrow passages between grains. Once filtered, these aggregates then served as preferred sites for attachment of other hydrophobic colloids. The hydrophilic colloids were retained primarily in a thin film of water at the edge of the menisci, the air–water–solid (AWS) interface. Centrifugal motion within the pendular rings observed in the videos contributed to movement of the colloids toward the AWS interface, where colloids were retained due to both low laminar flow velocities near the grain surface and straining in the thin water film at the edge of the meniscus. Except near the solid interface, sorption at the air–water (AW) interface was not observed and appeared unimportant to the retention of colloids. The findings form an essential link between colloid retention and transport processes at the interfacial, pore, and Darcy scales.
Glenberg's embodied memory: Less than meets the eye

We are sympathetic to most of what Glenberg says in his target article, but we consider it common wisdom rather than something radically new. Others have argued persuasively against the idea of abstraction in cognition, for example. On the other hand, Hebbian connectionism cannot get along without the idea of association, at least at the neural level.
Inducible control of tissue-specific transgene expression in Xenopus tropicalis transgenic lines.

Analysis of gene function in vertebrates is facilitated by gain-of-function studies, such as injection of synthetic mRNA in amphibian embryos. This approach is hampered by lack of spatial and temporal control of expression of the introduced gene product. An additional level of control is obtained by nuclear-transfer-mediated transgenesis, but functional analyses are complicated by variability and background abnormalities in primary transgenic embryos. The GAL4/UAS system permits establishment of stable lines and elimination of nuclear-transfer-associated abnormalities, through generation of separate UAS-'effector' and GAL4 'transactivator' transgenic lines. When the GAL4 DNA-binding domain is combined with a steroid hormone ligand-binding domain, this system allows full temporal regulation of transgene expression by introduction of an exogenous steroid analogue, the progesterone antagonist RU486. We show here that by crossing stable Xenopus tropicalis transgenic lines, one bearing a UAS-enhanced cyan fluorescent protein (ECFP) reporter construct, and the other with a GAL4-progesterone receptor fusion driven by a retina-specific promoter, reporter expression in the resulting embryos can be induced with RU486 in a tissue-specific manner. These results suggest that the inducible binary system, in which the target gene expression can be controlled in a stage- and tissue-specific pattern, should be readily applicable for gene function studies at all stages of development.
The Physiologic Effects of Extended Wear Soft Contact Lenses

The major physiologic effect to the eyes of soft contact lenses in general and continuously worn hydrogel lenses in particular is a decrease in the amount of oxygen normally available to the cornea. This reduction in oxygen supply produces changes as minimal as clinically undetectable epithelial edema and as severe as the anoxic overwear syndrome that produces pain and decreased vision. Induced corneal edema can produce refractive error changes and endothelial cell changes. On a long-term basis the lenses produce physical trauma to the anterior surface of the cornea as well as certain metabolic changes and have been associated with a significant degree of corneal neovascularization. Because hydrogel lenses require a different type of care than standard, hard PMMA lenses, new complications are being described, such as giant papillary conjunctivitis, lens deposits, and acute red eye syndromes that may be associated with allergic or toxic reactions to preservatives used in the cleaning processes. Research is underway to develop hydrogel materials that will allow more oxygen to reach the corneal surface and prevent surface deposits from forming.
Knowledge-guided multi-scale independent component analysis for biomarker identification

Many statistical methods have been proposed to identify disease biomarkers from gene expression profiles. However, from gene expression profile data alone, statistical methods often fail to identify biologically meaningful biomarkers related to a specific disease under study. In this paper, we develop a novel strategy, namely knowledge-guided multi-scale independent component analysis (ICA), to first infer regulatory signals and then identify biologically relevant biomarkers from microarray data. Since gene expression levels reflect the joint effect of several underlying biological functions, disease-specific biomarkers may be involved in several distinct biological functions. To identify disease-specific biomarkers that provide unique mechanistic insights, a meta-data "knowledge gene pool" (KGP) is first constructed from multiple data sources to provide important information on the likely functions (such as gene ontology information) and regulatory events (such as promoter responsive elements) associated with potential genes of interest. The gene expression and biological meta data associated with the members of the KGP can then be used to guide subsequent analysis. ICA is then applied to multi-scale gene clusters to reveal regulatory modes reflecting the underlying biological mechanisms. Finally disease-specific biomarkers are extracted by their weighted connectivity scores associated with the extracted regulatory modes. A statistical significance test is used to evaluate the significance of transcription factor enrichment for the extracted gene set based on motif information. We applied the proposed method to yeast cell cycle microarray data and Rsf-1-induced ovarian cancer microarray data. The results show that our knowledge-guided ICA approach can extract biologically meaningful regulatory modes and outperform several baseline methods for biomarker identification. We have proposed a novel method, namely knowledge-guided multi-scale ICA, to identify disease-specific biomarkers. The goal is to infer knowledge-relevant regulatory signals and then identify corresponding biomarkers through a multi-scale strategy. The approach has been successfully applied to two expression profiling experiments to demonstrate its improved performance in extracting biologically meaningful and disease-related biomarkers. More importantly, the proposed approach shows promising results to infer novel biomarkers for ovarian cancer and extend current knowledge.
Effect of Water Drag on Diffusion of Drifting Polarons in DNA

It has been shown, theoretically and experimentally, that a hole or an excess electron on a DNA molecule in solution forms a delocalized wave function, a polaron. For an all-adenine (A) sequence or a mixed sequence of guanines (G's) and A's, calculations taking into account the polarization of the solution give the wave function spread over approximately four bases, which appears to be in agreement with experiment. The polaron may move by hopping or by drift. Drift can take place in a region with all the same bases, for example, A's, by the polaron dropping an A on the trailing edge and picking up an A on the leading edge. For drift that is not too rapid, the necessity of the polarization changing as the polaron moves exerts a drag on the polaron. We calculate the drag by using a model introduced earlier to describe the polaron. We find the drag to be proportional to the velocity of the polaron and to the orientational relaxation time of the water molecules. The drag is also a function of the Coulomb interactions of the fractional charges on the bases constituting the polaron, as modified by the polarization charge induced in the solution. The diffusion rate and mobility for all A polarons, calculated taking into account the drag, are 8 x 10 -5 cm 2 /s and 3 x 10 -3 cm 2 /(V s), respectively. We believe that in the experimental studies that have been carried out on hole propagation in a series of A's it was drift being observed rather than the hopping of a localized hole between adjacent A's, as was assumed to be the case.
Galanin in the hypothalamus raises dopamine and lowers acetylcholine release in the nucleus accumbens: a possible mechanism for hypothalamic initiation of feeding behavior

Rats were prepared with two implanted guide shafts, one for microdialysis to measure extracellular dopamine (DA) and acetylcholine (ACh) in the posterior, medial nucleus accumbens (NAc), and the other for microinjection of galanin, neuropeptide Y or saline in the hypothalamic paraventricular nucleus (PVN). There was an increase in DA release and a decrease in ACh in the NAc following microinjections of galanin into the PVN. The effect was observed only in rats for which identical galanin injections induced feeding in separate tests. Ringer injections had no effects. Unlike galanin, neuropeptide Y in the PVN induced eating without altering DA/ACh; whereas earlier results showed that norepinephrine in the PVN works like galanin. These results suggest that galanin initiates feeding, in part, by activating the mesolimbic DA system and suppressing intrinsic cholinergic activity in the NAc. This may prime instrumental behavior with DA while disinhibiting behavior by lowering ACh.
Semi-empirical LCAO-xα theory for transition metal complexes. II. Application to ionization potentials

Abstract Ionization potentials for 17 n d-transition metal complexes are calculated by a semi-empirical LCAO-Xα theory excluding ( n + 1)s and (n + 1)p atomic orbitals. The results agree well with both photoelectron data and discrete-variational Xα results, which include the ( n + 1) atomic orbitals. Implications of the ( n + 1)-atomic orbital exclusion are noted. Also, new assignments for photoelectron spectra of VCl 3 0, MnCl 3 O, CrCl 2 O 2 , and MoCl 2 O 2 are proposed.
The rise of Network Ecology: Maps of the topic diversity and scientific collaboration

Network ecologists investigate the structure, function, and evolution of ecological systems using network models and analyses. For example, network techniques have been used to study community interactions (i.e., food-webs, mutualisms), gene flow across landscapes, and the sociality of individuals in populations. The work presented here uses a bibliographic and network approach to (1) document the rise of Network Ecology, (2) identify the diversity of topics addressed in the field, and (3) map the structure of scientific collaboration among contributing scientists. Our aim is to provide a broad overview of this emergent field that highlights its diversity and to provide a foundation for future advances. To do this, we searched the ISI Web of Science database for ecology publications between 1900 and 2012 using the search terms for research areas of Environmental Sciences & Ecology and Evolutionary Biology and the topic ecology. From these records we identified the Network Ecology publications using the topic terms network, graph theory, and web, while controlling for the usage of misleading phrases. The resulting corpus entailed 29,513 publications between 1936 and 2012. We found that Network Ecology spans across more than 1500 sources with core ecological journals being among the top 20 most frequent outlets. We document the rapid rise in Network Ecology publications per year reaching a magnitude of over 5% of the ecological publications in 2012. Drawing topical information from the publication record content (titles, abstracts, keywords) and collaboration information from author listing, our analysis highlights the diversity and clustering of topics addressed within Network Ecology. The largest connected component of the topic network contained 73% of the corpus, and exhibited strong clustering (clustering coefficient 0.93). The co-authorship network revealed that while network ecologists are generally collaborative, the field is deeply fragmented into topic and co-author cliques. The largest component of the co-author network comprised 46% of the authors and contained 149 distinct clusters. We suggest ways to build on the collaborative spirit and reduce the field fragmentation so as to improve the development and spread of ideas. We conclude that Network Ecology will likely continue to grow because the forces driving its increase are likely to persist.
Charge of the mito brigade. Focus on "Changes in mitochondrial surface charge mediate recruitment of signaling molecules during apoptosis".

the role of mitochondria as the foci of apoptotic signaling events in physiological and pathological conditions is now well-established (12). Multiple studies have demonstrated the recruitment of various cytosolic effector proteins, such as caspase-8, Bax, and Bak, to the outer membrane surface of mitochondria in apoptotic cells. Other reports have documented the redistribution of pro-apoptotic proteins, such as cytochrome c and Smac/Diablo, from the intermembrane space to the mitochondrial outer membrane (MOM) or the cytosol. The assembly of these newly recruited or transferred proteins into apoptotic signaling complexes, such as the Bax/Bak-based pores that mediate MOM permeabilization, has also been extensively characterized. Although the mechanisms by which apoptotic effector proteins recognize the MOM as a specific subcellular platform remain incompletely understood, recent studies have identified cardiolipin (CL), a predominantly mitochondrial phospholipid, as a key “targeting” factor (4, 6, 13). Both tBid (the pro-apoptotic truncated form of Bid) and caspase-8 bind to CL and disruption of these CL-effector protein interactions markedly attenuates the progression of apoptosis. Notably, association of these pro-apoptotic proteins with CL can involve stereospecific sites such as the hairpin motif within tBid formed by its α-6 helix (αH6) domain but independent of its BH3 domain (5, 11). However, CL is also dianionic at physiological pH and thus contributes to the overall surface charge of membranes in which it is abundant. In this issue of AJP-Cell Physiol, Heit et al. (8) report that mitochondria rapidly gain negative surface charge, likely due to increased CL in the outer membrane, during the early phases of apoptosis. Based on CL neutralization approaches, this study from Grinstein's group supports a novel and mechanistically significant model wherein mitochondrial exposure of negatively charged CL facilitates the electrostatic recruitment of multiple cationic proteins required for the progression of critical apoptotic signaling events.
Infrared imagery of ocean internal waves

[1] Infrared imaging provides a new way to detect internal waves under conditions where techniques that rely on backscatter from the sea surface may not be effective and it provides a new means to investigate the spatial variability associated with internal waves. This is illustrated with imagery collected in a bay under light winds using an airborne infrared camera. The internal waves appear as groups of dark and bright bands, corresponding to surface temperature fluctuations of about 0.05°C. A signal of this size is shown to be plausible based on straining of the water's surface thermal boundary layer (‘cool skin’) by internal waves having a strain rate of the order of 10−2 s−1. In addition, fine-scale temperature structure was detected that we speculate may indicate instabilities induced by the internal waves.
The internet as a new distribution channel of scientific grey literature: The case of Italian WWW servers

The enormous range of information sources and communication services available on the Internet today recalls the information explosion and information overload that characterizes this century. We are certainly facing new kinds of information and communication patterns, based on direct electronic communication between end-users among themselves and/or between end-users and information sources. Moreover, this new channel of communication provides the opportunity to distribute different types of information, which in some cases are available only in a networked environment. The aim of this article is to analyze whether this new scenario has stimulated the production and the direct distribution of grey literature as well as changing its “traditional” features. The starting point of the study are the Italian WWW servers of the National Research Council.
Mitochondrial dysfunction modulates nonlinear dynamics in liver cell metabolism

Regulatory dynamics of energy metabolism in living cells entails a coordinated response of multiple enzyme networks that operate under non-equilibrium conditions. Here we show that mitochondrial dysfunctions associated with the aging process significantly modify nonlinear dynamical signatures in free radical generation/removal thereby altering energy metabolism in liver cells. Combining high spatial and temporal resolution imaging and bio-energetic measurements, our work provides experimental support to the hypothesis that mitochondria manifest nonlinear dynamical behavior for efficiently regulating energy metabolism in intact cells and any partial or complete reduction in this behavior would contribute to organ dysfunctions including aging process and other disease processes.
Backscatter cross sections of composite random rough surfaces based on the selection of variational parameters to determine the surface height spectral densities of the larger-and smaller-scale surfaces

No single scattering theory can be used to evaluate the scatter cross sections of surfaces with multiple scales of roughness. In this paper a two-scale unified full-wave approach is used to evaluate the backscatter cross sections for vertically and horizontally polarized waves. The total cross sections are expressed analytically as weighted sums of a tilt-modulated smaller-scale surface height backscatter cross section and a larger-scale surface physical optics backscatter cross section, reduced by the square of the smaller-scale surface characteristic function. Consistent with the large radii of curvature criteria, only the slopes of the larger-scale surface contribute to tilt modulation. Unlike the conventional hybrid perturbation/physical optics solutions, the unified full-wave approach used here is not restricted to small Rayleigh roughness parameters. The total surface is decomposed continuously and smoothly into smaller-and larger-scale surfaces. It is shown that the total backscatter cross sections are stationary over a very broad range of the variational parameters, proportional to the ratio of the mean square slopes or heights of the larger-scale surface and the total surface. At grazing angles of incidence, the vertically and horizontally polarized cross sections are shown to be of the same order of magnitude, consistent with recent experimental data. This is because at grazing angles, tilt modulation impacts significantly on the horizontally polarized cross sections and marginally upon the vertically polarized cross sections. This is consistent with the observation that the original full-wave solutions (that do not account for tilt modulation) underestimate the values for the horizontally polarized cross sections. These investigations also impact on the feasibility of relating the backscatter cross sections to the remote sensing of soil moisture content.
Depressive symptoms and marital satisfaction: within-subject associations and the moderating effects of gender and neuroticism.

Given the emphasis on within-subject associations between depression and marital quality in recent theory and practice, this study was undertaken with three goals: to examine within-subject associations between depressive symptoms and marital quality over time, to address gender differences in the magnitude and direction of these associations, and to determine whether neuroticism moderates the strength of these associations. A total of 164 newly wed couples provided 8 waves of data over 4 years of marriage. Hierarchical linear modeling confirmed the existence of bidirectional within-subject associations between marital satisfaction and depressive symptoms. Gender differences were rarely significant. Although neuroticism strengthened the effect of marital distress on symptoms as predicted, it weakened the effect of symptoms on marital distress among husbands. The theoretical and practical implications of these findings are discussed.
Nitrene addition to exfoliated graphene: a one-step route to highly functionalized graphene

We demonstrate a high yield method of functionalizing graphene nanosheets through nitrene addition of azido-phenylalanine [Phe(N3)] to exfoliated micro-crystalline graphite (μG). This method provides a direct route to highly functionalized graphene sheets. TEM analysis of the product shows few layer (n < 5) graphene sheets. The product was determined to have 1 phenylalanine substituent per 13 carbons.
Skeletal element abundances in archaeofaunal assemblages: economic utility, sample size, and assessment of carcass transport strategies

Economic utility indices provide a means of interpreting butchery and transport decisions reflected in the relative abundance of skeletal elements. Because of destructive taphonomic processes, interpreting skeletal element abundances in terms of carcass transport strategies requires that faunal analysts consider only those elements which accurately reflect their original abundances following human discard. In this study we use resampling techniques to examine the impact of sample size on correlations between high-survival skeletal element frequencies and economic utility in four simulated population assemblages reflecting distinct carcass transport strategies. Correlations alone do not accurately reflect the true relationship between bone abundance and economic utility as particular transport strategies have a tendency to generate high frequencies of Type II errors as sample size decreases. We show that the Shannon evenness index can be used as a quantitative means of distinguishing between bone assemblages characterized by subtle variations in skeletal element abundances. The evenness index can also be used to evaluate whether observed correlations reflect sampling error. Results from our simulations are applied to three published faunal assemblages to evaluate likely carcass transport strategies.
Wave Scattering by an Inclusion Having Imperfect Interfaces with the Matrix

Ultrasonic waves have been used in recent years to detect defects and damages in fiber-reinforced composite materials (see [1] for relevant references). A priori knowledge of how sound wave propagates through the composite medium is essential for using ultrasonic techniques in nondestructive evaluation. In the past, the problern of scattering by inclusions, such as fibers, has been studied extensively [2]–[3]. Most of the studies in the literature assume that the inclusions are perfectly boned to the matrix. However, defects are likely to exist along the fiber—matrix interfaces. As more interfacial defects are initiated, damages are developed within a layer of materials near the interface which will eventually lead to complete fiber debonding. Since interfacial damages may adversely affect the overall strength of the composites, it is important to be able to characterize and monitor the damage accumulation during manufacturing processes and engineering applications of the composites. Thus, developing theories and techniques to characterize interfacial strength, toughness and the amount of damages is warranted. To serve this purpose, the effects of interfacial damages on the behavior of wave propagation in fiber-reinforced composites need to be studied.
Recovery of Bandlimited Signals from Unequally Spaced Samples

A method of recovering bandlimited signals from unequally spaced samples is described. The method uses an iterative procedure which requires low pass filtering of the unequally spaced sample pulses. This is followed by resampling at the same unequally spaced times and again low pass filtering to obtain a correction signal. Repeated application of this process is shown to converge to the original signal. These results are obtained by slight modifications of the analysis in Reference 2.
Focused Approach to Parathyroidectomy

Minimally invasive parathyroidectomy is performed after preoperative parathyroid localization-usually with high-quality sestamibi scans and/or ultrasonography-often under cervical block anesthesia during which a limited exploration is performed. The rapid intraoperative parathyroid hormone assay is then employed to confirm an adequate resection and cure of primary hyperparathyroidism. This article discusses imaging, anesthesia, results, and the surgical management of patients undergoing minimally invasive parathyroidectomy.
Endogenous Parties in an Assembly

In this article, I show how members of an assembly form voting blocs strategically to coordinate their votes and affect the policy outcome chosen by the assembly. In a repeated voting game, permanent voting blocs form in equilibrium. These permanent voting blocs act as endogenous political parties that exercise party discipline. In a stylized assembly I prove that the equilibrium parties must be two small polarized voting blocs, one at each side of the ideological divide.
Efficiency of thread-level speculation in SMT and CMP architectures - performance, power and thermal perspective

Computer industry has adopted multi-threaded and multi-core architectures as the clock rate increase stalled in early 2000psilas. However, because of the lack of compilers and other related software technologies, most of the general-purpose applications today still cannot take advantage of such architectures to improve their performance. Thread-level speculation (TLS) has been proposed as a way of using these multi-threaded architectures to parallelize general-purpose applications. Both simultaneous multithreading (SMT) and chip multiprocessors (CMP) have been extended to implement TLS. While the characteristics of SMT and CMP have been widely studied under multi-programmed and parallel workloads, their behavior under TLS workload is not well understood. The TLS workload due to speculative nature of the threads which could potentially be rollbacked and due to variable degree of parallelism available in applications, exhibits unique characteristics which makes it different from other workloads. In this paper, we present a detailed study of the performance, power consumption and thermal effect of these multithreaded architectures against that of a Superscalar with equal chip area. A wide spectrum of design choices and tradeoffs are also studied using commonly used simulation techniques. We show that the SMT based TLS architecture performs about 21% better than the best CMP based configuration while it suffers about 16% power overhead. In terms of Energy-Delay-Squared product (ED2), SMT based TLS performs about 26% better than the best CMP based TLS configuration and 11% better than the superscalar architecture. But the SMT based TLS configuration, causes more thermal stress than the CMP based TLS architectures.
Spatial tuning of negative and positive Poisson’s ratio in a multi-layer scaffold

While elastic modulus is tunable in tissue engineering scaffolds, it is substantially more challenging to tune the Poisson’s ratio of scaffolds. In certain biological applications, scaffolds with a tunable Poisson’s ratio may be more suitable for emulating the behavior of native tissue mechanics. Here, we design and fabricate a scaffold, which exhibits simultaneous negative and positive Poisson’s ratio behavior. Custom-made digital micro-mirror device stereolithography was used to fabricate single- and multiple-layer scaffolds using polyethylene glycol-based biomaterial. These scaffolds are composed of pore structures having special geometries, and deformation mechanisms, which can be tuned to exhibit both negative Poisson’s ratio (NPR) and positive Poisson’s ratio (PPR) behavior in a side-to-side or top-to-bottom configuration. Strain measurement results demonstrate that analytical deformation models and simulations accurately predict the Poisson’s ratios of both the NPR and PPR regions. This hybrid Poisson’s ratio property can be imparted to any photocurable material, and potentially be applicable in a variety of biomedical applications.
Mitral valve strands in patients with focal cerebral ischemia

Background and Purpose Filamentous strands attached to the mitral valve are a recently described finding in occasional patients undergoing transesophageal echocardiography (TEE), but the frequency and clinical significance of these strands remain poorly defined. The purpose of the present study was to review the prevalence of mitral valve strands in patients undergoing TEE examination and to explore the relation of these strands to cardioembolic cerebral ischemia. Methods All patients with native mitral valves referred for clinically indicated TEE over a 2-year period at our institution were evaluated for the presence of mitral valve strands (defined as highly mobile filamentous masses <1 mm thick attached to the atrial surface of mitral leaflets). Results Of 968 study patients, mitral valve strands were identified in 22 individuals (2.3%). Mitral valve strands were significantly more common in patients referred for TEE as a result of a recent ischemic cerebrovascular event compared with patients referred...
Sea Ice Ecosystems

Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters.
Compartment shape anisotropy (CSA) revealed by double pulsed field gradient MR

The multiple scattering extensions of the pulsed field gradient (PFG) experiments can be used to characterize restriction-induced anisotropy at different length scales. In double-PFG acquisitions that involve two pairs of diffusion gradient pulses, the dependence of the MR signal attenuation on the angle between the two gradients is a signature of restriction that can be observed even at low gradient strengths. In this article, a comprehensive theoretical treatment of the double-PFG observation of restricted diffusion is presented. In the first part of the article, the problem is treated for arbitrarily shaped pores under idealized experimental conditions, comprising infinitesimally narrow gradient pulses with long separation times and long or vanishing mixing times. New insights are obtained when the treatment is applied to simple pore shapes of spheres, ellipsoids, and capped cylinders. The capped cylinder geometry is considered in the second part of the article where the solution for a double-PFG experiment with arbitrary experimental parameters is introduced. Although compartment shape anisotropy (CSA) is emphasized here, the findings of this article can be used in gleaning the volume, eccentricity, and orientation distribution function associated with ensembles of anisotropic compartments using double-PFG acquisitions with arbitrary experimental parameters.
Toxicity and Toxicokinetics of Pentachlorophenol and Carbaryl to Pontoporeia hoyi and Mysis relicta

Two Great Lakes invertebrates, the amphipod Pontoporeia hoyi and the mysid shrimp Mysis relicta, were exposed to pentachlorophenol (PCP) and carbaryl to determine actue mortality. At pH 8, the LCSo for P. hoyi after 96 h was 0.6 f 0.3 pg mL-I for PCP, while that for carbaryl was 0.23 f 0.04 pg mL-'. The LCso for M. relicta at pH 8 and 96 h was 54.1 k 10.3 pg mL-' for PCP and for carbaryl0.23 pg mL-I (0.103 -0.356, n = 2). The differences in the LC5o values between P. hoyi and M. relicta for PCP result in part from differences in the uptake clearances of the two animals, 3.1 +_ 0.9 mL g-I h-I for P. hoyi compared to 0.4 ? 0.1 mL g-' h-I for M. relicta. A similar difference occurred in the respective carbaryl uptake clearances for the two organisms, 3.74 _+ 0.63 mL g-I hK1 for P. hoyi and 0.134 mL g-I h-I (0.135 to 0.133, n = 2) for M. relicta. The cumulative toxicant concentrations in the organisms that result in 50% mortality, L&,, were estimated from a toxicokinetics model that was para- meterized with the measured uptake and elimination constants and the LCSo values. The M. relicta LD50 for PCP was approximately ten times larger than that for P. hoyi and confirmed the relative sensitivities of the organisms as described by their respective LC50 values. For car- baryl, the LDSo for P. hoyr was greater than that for M. relicta. Thus M. relicta is apparently more sensitive to accumulated carbaryl than P. hoyi despite the similar LC5o values for the two organisms.
EXPERIMENTAL INDUCTION OF ATHERO-ARTERIOSCLEROSIS BY THE SYNERGY OF ALLERGIC INJURY TO ARTERIES AND LIPID-RICH DIET I. EFFECT OF REPEATED INJECTIONS OF HORSE SERUM IN RABBITS FED A DIETARY CHOLESTEROL SUPPLEMENT

In rabbits that received a dietary supplement of cholesterol, 0.5% by weight, and concommittant injections of horse serum (group III) over a period of 80 days, coronary arterial lesions developed that in the main were different in quality and distribution from those in rabbits that received the cholesterol supplement alone (group I), and of different quality from but in distribution similar to those in rabbits that received horse serum alone (group II). Fatty lesions developed in small, rarely in medium, but never in large arteries of rabbits in group I, and these changes do not resemble coronary athero-arteriosclerosis in man. Proliferative lesions without fatty change developed in large, medium, and small arteries of rabbits in group II, and some of these closely resemble human coronary arteriosclerosis without fatty change. The changes that developed in large, medium, and small arteries of rabbits in group III were in very large majority fatty-proliferative lesions. Some of these closely resemble the changes that in some cases constitute coronary athero-arteriosclerosis in man. Nuclei with caterpillarlike chromatin pattern in longitudinal section and owl eye appearance in transverse section were observed to occur in many of the proliferating cells in thickened arterial intima in hearts of rabbits in groups II and III and in some of the lipid rich "foam" cells in arterial intima and subjacent media in hearts of rabbits in group III. Such nuclei have been observed to occur in some reacting smooth muscle cells and normal immature and reacting mature striated muscle cells of the heart. These observations indicate that at least many of the cells, including "foam" cells, in thickened intima in the experimentally induced and in naturally occurring coronary athero-arteriosclerosis are smooth muscle cells that evolved in proliferative reaction to arterial injury. Fatty change developed in aortas of the rabbits in groups I and III, and was significantly greater in group III. Results of this investigation support the hypothesis that the synergy of allergic injury to arteries and lipid-rich diet can lead to athero-arteriosclerosis.
Backscattering enhancement: from radar cross sections, to electron and light localizations to rough surface scattering

The historical development of backscattering enhancement and recent work are reviewed. Three topics are discussed. They are: enhanced radar cross section and scintillation index in turbulence and enhanced imaging, enhanced backscattering from particles and photon localization, and enhanced backscattering from rough surfaces. >
Amniotic fluid homocysteine levels, 5,10-methylenetetrahydrafolate reductase genotypes, and neural tube closure sites.

A specific gene mutation leading to altered homocysteine metabolism has been identified in parents and fetuses with neural tube defects (NTDs). In addition, current animal and human data indicate that spine closure occurs simultaneously in five separate sites that then fuse. We sought to determine whether either this mutation or abnormal amniotic fluid homocysteine levels are associated with all five neural tube closure sites. We retrieved stored amniotic fluid from cases of isolated fetal neural tube defect diagnosed from 1988 to 1998 (n = 80) and from normal controls matched for race, month and year of amniocentesis, and maternal age. Cases were categorized according to defect site by using all available medical records. The presence or absence of the 677C-->T mutation of 5, 10-methylenetetrahydrafolate reductase (MTHFR) gene was determined, and homocysteine levels were measured; case and controls were compared. Significantly more cases than controls were heterozygous or homozygous for the 677C-->T MTHFR mutation (44% vs. 17%, P 90th centile (>1.85 micromol/L), 27% vs. 10%, P = 0.02. Most (83%) of control cases had both normal MTHFR alleles and normal amniotic fluid homocysteine levels (normal/normal), whereas only 56% of NTD case were normal/normal (P = 0.001). When evaluated by defect site, only defects involving the cervical-lumbar spine, lumbosacral spine, and occipital encephalocele were significantly less likely to be normal/normal than controls (P = 0.007, 0.0003, and 0.007, respectively), suggesting a strong association with the 677C-->T allele. In contrast, anencephaly, exencephaly, and defects confined to the sacrum included many cases that had both normal MTHFR alleles and normal homocysteine and were not significantly different from controls. The 677C-->T MTHFR mutation and elevated homocysteine levels appear to be disproportionately associated with defects spanning the cervical-lumbar spine, lumbosacral spine, and occipital encephalocele. In contrast, anencephaly, exencephaly, and defects confined to the sacrum may not be related to altered homocysteine metabolism.
Left atrial roof ablation is more important than pulmonary vein isolation in terminating persistent atrial fibrillation in a canine model should we perform a left atrial roof line in all atrial fibrillation ablations

Left atrial (LA) ablation for persistent atrial fibrillation (AF) as performed in most electrophysiology laboratories in 2010 has developed from an amalgamation of several different approaches. The idea that rapidly discharging atrial tachycardia foci usually located in the pulmonary veins could
Adenoviral Vector Targeting via Mitigation of Liver Sequestration

Only a few diseases can be addressed by delivering genes or vectors to a single tissue. In many cases, systemic delivery by intravenous injection will be the best approach to deliver therapeutic viruses throughout the body. Although the intravenous route is appealing, adenoviruses are bound and sequestered by an overlapping arsenal of antipathogen elements that inactivate or mistarget these therapeutics. These include interactions with natural antibodies, adaptive antibodies, blood factors, complement, blood cells, endothelial cells, Kupffer cells, macrophages, and liver hepatocytes. Many of these interactions occur by binding to the 720 copies of the hexon protein that is a multivalent patterned surface on adenovirus icosahedrons. We describe here our current understanding of interactions with the adenovirus hexon and methods to avoid loss of viruses during systemic therapy.
Professor Ayer on Individuals

A RE individuating terms, or 'indicators' as Prof. A. J. Ayer calls them, nothing more than shorthand predicates? In what does the distinction between individual and property consist? These questions are expounded and somewhat uncertainly answered by Prof. Ayer in a recent article.' The principal points of Prof. Ayer's showing are, I believe, the following. Predicative expressions may be taken to signify situations and to apply to occasions, the terms ' situation' and 'occasion' being undefined though a situation is something capable of exemplification and is repeatable, and an occasion is what exemplifies a situation and is not repeatable. A situation can always be re-expressed in terms of occasions : Prof. Ayer's writing his paper is an occasion, and it exemplifies the situation of a person writing, as well as numerous other situations. Occasions must be empirical. Expressions for situations must accordingly admit of translation into terms signifying observable things. The question, Are indicators shorthand predicates?, can be resolved into three other questions: (a) For every descriptive 1 Mind, Vol. LXI, No. 244. 37