cssi/SciSciGPT-SciSciNet huggingface dataset:
Experimental Study of Thermoelectric Properties of SWCNTs and SiC Nanoparticles and its Composites Doped With Sol-Gels

Thermoelectric (TE) properties of Single wall carbon nanotubes (SWCNTs) and Silicon carbide (SiC) nanoparticles after treated with sol-gel dopants at elevated temperature. Different combinations of P and N type sol-gels were used. The combinations were Boron-Antimony, Aluminum-Antimony, Aluminum-Phosphorus and Boron–Phosphorus. The nanoparticles were randomly distributed on a nonconductive glass substrate and hot and cold junctions were created using silver epoxy and Alumel (Ni-Al) wire. The carbon nanotubes used were approximately 60% semiconducting and 40% metallic. Voltage (mV), current (μA) and resistance (Ω) were measured across the distributed nanoparticles within 160° C temperature difference. The Seebeck coefficient for pristine SWCNTs was 0.12 mV/oC. When doped with Boron-Antimony the Seebeck coefficient increased to 0.981 mV/°C. On the hand, SiC nanoparticles showed no TE effect at pristine form, but when infused with SWCNTs substantial TE effect was present. Even though the Seebeck coefficient was in a similar range with different SWCNT concentrations (wt%), current, resistance and Power factor (P.F.) changed with wt% of nanotubes. Resistance of the nanotube samples slightly decreased with the increase in temperature. Finally, the SiC+SWCNT composites were prepared using the sintering process at around 1500° C. Thermoelectric and Mechanical properties of the composites were tested. The structure-property relation was analyzed using SEM (scanning electron microscope) and XRD (X-ray diffraction). It was revealed that fiber like SWCNTs created randomly distributed network with Nano contact junctions inside the SiC matrix and enhance thermoelectric and mechanical properties in the combined SiC+SWCNTs material system. Put abstract text here.Copyright © 2013 by ASME
Targeted cancer therapy – Are the days of systemic chemotherapy numbered?

Targeted therapy or molecular targeted therapy has been defined as a type of treatment that blocks the growth of cancer cells by interfering with specific cell molecules required for carcinogenesis and tumor growth, rather than by simply interfering with all rapidly dividing cells as with traditional chemotherapy. There is a growing number of FDA approved monoclonal antibodies and small molecules targeting specific types of cancer suggestive of the growing relevance of this therapeutic approach. Targeted cancer therapies, also referred to as "Personalized Medicine", are being studied for use alone, in combination with other targeted therapies, and in combination with chemotherapy. The objective of personalized medicine is the identification of patients that would benefit from a specific treatment based on the expression of molecular markers. Examples of this approach include bevacizumab and olaparib, which have been designated as promising targeted therapies for ovarian cancer. Combinations of trastuzumab with pertuzumab, or T-DM1 and mTOR inhibitors added to an aromatase inhibitor are new therapeutic strategies for breast cancer. Although this approach has been seen as a major step in the expansion of personalized medicine, it has substantial limitations including its high cost and the presence of serious adverse effects. The Cancer Genome Atlas is a useful resource to identify novel and more effective targets, which may help to overcome the present limitations. In this review we will discuss the clinical outcome of some of these new therapies with a focus on ovarian and breast cancer. We will also discuss novel concepts in targeted therapy, the target of cancer stem cells.
Writing in Web-based Disciplinary Courses: New Media, New Disciplinary Composing Expectations

Abstract Scholarship in Online Writing Instruction has offered many suggestions to facilitate web-based writing pedagogy; however, little research examines how faculty in other disciplines use writing assignments and related technologies for web-based courses in their own discipline. This article reports on the findings of two surveys of disciplinary faculty at a large Midwestern, state-supported university regarding composing assignments they use in upper-division courses, particularly differences in assignments and assessment criteria related to the course delivery mode—classroom-based versus web-based. I identify a handful of distinctions of writing assignments used and expectations of composing skills in web-based upper division disciplinary courses compared with such classes delivered via the classroom environment. These include: the kinds of composing assignments used, digital literacy expectations and where such skills ought to be learned, and criteria deemed important. Also, I discuss how class size, instructor training in web-based pedagogy, training in assessment of multimodal projects, and the degree to which a program has web-based offerings can affect these attributes. These findings and related discussion encourage further focused study on composing demands in web-based coursework. Such research can help writing faculty understand on which particular skills to focus instruction in first-year writing courses, given the proliferation of web-based courses, and it can help program administrators develop strong survey instruments to facilitate assessment at their own institution.
Thrombosis in systemic lupus erythematosus: risk and protection.

Thrombotic events occur with higher frequency in patients with systemic lupus erythematosus (SLE) than in the general population and are associated with poor outcomes. In addition to the traditional risk factors, other predisposing factors for thrombosis, such as ethnicity, disease duration, disease activity, nephritis, hypertension and, most importantly, the presence of antiphospholipid antibodies, associated or not with the antiphospholipid syndrome, have been reported in patients with SLE. On the other hand, aspirin and antimalarial medications may have a protective thrombotic effect in these patients. Strategies to prevent thrombosis occurrence should be part of the management of patients with SLE; thus, aPL antibodies should be screened in all lupus patients, especially if other risk factors are also present. Stratification of the risks of thrombotic events, smoking cessation and the use of protective medications are important elements of thrombosis prevention. To date, no laboratory test can predict...
Animal models of catheter-induced intimal hyperplasia in type 1 and type 2 diabetes and the effects of pharmacologic intervention

Diabetes is a complex disorder characterized by impaired insulin formation, release or action (insulin resistance), elevated blood glucose, and multiple long-term complications. It is a common endocrine disorder of humans and is associated with abnormalities of carbohydrate and lipid metabolism. There are two forms of diabetes, classified as type 1 and type 2. In type 1 diabetes, hyperglycemia is due to an absolute lack of insulin, whereas in type 2 diabetes, hyperglycemia is due to a relative lack of insulin and insulin resistance. More than 90% of people with diabetes have type 2 with varied degrees of insulin resistance. Insulin resistance is often associated with impaired insulin secretion, and hyperglycemia is a common feature in both types of diabetes, but failure to make a distinction between the types of diabetes in different animal models has led to confusion in the literature. This is particularly true in relation to cardiovascular disease in the presence of diabetes and especially the response to vascular injury, in which there are major differences between the two types of diabetes. Animal models do not completely mimic the clinical disease seen in humans. Animal models are at best analogies of the pathologic process they are designed to represent. The focus of this review is an analysis of intimal hyperplasia following catheter-induced vascular injury, including factors that may complicate comparisons between different animal models or between in vitro and in vivo studies. We examine the variables, pitfalls, and caveats that follow from the manner of induction of the injury and the diabetic state of the animal. The efficacy of selected antidiabetic drugs in inhibiting the development of the hyperplastic response is also discussed.
Degeneration of rat thalamic reticular neurons following intrathalamic domoic acid injection.

Abstract Domoic acid (DA), an analog of kainic acid, produces attentional deficits in humans who have ingested shell fish contaminated with this excitotoxin. The thalamic reticular nucleus (RT), by virtue of its location, connections and intrinsic properties, has been implicated in attentional processes. This study demonstrated the vulnerability of RT neurons following intrathalamic DA injections in rats. Lesions were characterized by almost total neuronal loss throughout the RT and sparing of adjacent populations of relay neurons in the VL and VPL. Loss of RT neurons may underlie some types of attentional deficits observed in humans following DA poisoning.
Post-Chemotherapy Resection of Nonseminomatous Germ Cell Testicular Tumors Metastatic to the Mediastinum

AbstractPurpose: We determined if the behavior of germ cell tumors metastatic to the mediastinum is different from that of primary mediastinal germ cell tumors, a group known to have distinct clinical features.Materials and Methods: A search of the computerized data base for germ cell tumors metastatic to the mediastinum at our university revealed 80 patients, 65 of whom underwent concomitant retroperitoneal lymph node dissection at mediastinal surgery.Results: Of the patients 60 (75 percent) are free of disease, 14 (18 percent) died of cancer and 6 (8 percent) are living with disease. Mediastinal pathology included teratoma in 65 percent of the patients, cancer in 26 percent and fibrosis in 9 percent. Of the 65 patients who underwent retroperitoneal lymph node dissection 75 percent had teratoma, 15 percent had fibrosis and 10 percent had cancer. Mediastinal relapses after dissection were rare (4 of 80 patients).Conclusions: Germ cell tumors metastatic to the mediastinum appear to behave similarly to thos...
CONDITIONS FOR INACTIVATION OF BACTERIOPHAGES T1-T7 BY A POLYANION.

Abstract Inactivation of bacteriophages T 1 −T 7 by polyglucose sulfuric acid was studied under controlled conditions. Release of DNA indicating rupture of the phage head was prevented. Full inactivation of T 1 , T 3 and T 7 was achieved at pH 4.7, of T 2 at pH 4.2, of T 5 at pH 4.3 and of T 4 , T 6 and T 4−01 at pH 4.0. The inactivation curves showing the effects of temperature, pH and concentration of polyglucose sulfuric acid indicate that the odd members are closely related among themselves and the even members among themselves. Attempts to reverse inactivation were not successful. Incubation of the inactivated phage with putrescine and spermidine, or with bacteria at pH 5.6, failed to restore viability. The inactivated phages release their DNA in 0.2 M lysine at pH 8.8 and lose their ability to kill or lyse the bacteria, but retain normal attachment to Escherichia coli B. Ghosts treated with polyglucose sulfuric acid also lose bacterial-killing and -lysing abilities. It is suggested, therefore, that during the process of inactivation the proximal tail structure is damaged.
Effects of velocity shear and magnetic shear in the formation of core transport barriers in the DIII-D tokamak

Core transport barriers can be reliably formed in DIII-D by tailoring the evolution of the current density profile. This paper reports studies of the relative role of magnetic and shear in creating core transport barriers in the DIII-D tokamak and considers the detailed dynamics of the barrier formation. The core barriers seen in DIII-D negative shear discharges form in a stepwise fashion during the initial current ramp. The reasons for the stepwise formation are not known. Their extremely good shot to shot reproducibility suggests the steps are connected to a very reproducible plasma parameter such as the current density profile; however, the simple hypothesis that they occur each time q(0) or crosses an integer value is not consistent with all the data. The data from DIII-D are consistent with previous results that negative magnetic shear facilitates the formation of core transport barriers in the ion transport channel but is not necessary. However, strongly negative magnetic shear does allow formation of transport barriers in particle, electron thermal, ion thermal and angular momentum transport channels. Shots with strong negative magnetic shear have produced the steepest ion temperature and toroidal rotation profiles seen yet in DIII-D. In addition, the shearing rates seen in these shots exceed the previous DIII-D record value by a factor of four.
Ionic conductivity of thallium chloride

Abstract The conductivity of single crystals of thallium chloride has been measured with an a.c. impedance bridge. The results can be represented by the empirical formula σ = σ o exp (− W / kT ), with W = 0.82 eV and σ 0 = 5.3 × 10 3 (ohm-cm) −1 for 370–420°C, and W = 0.72 eV and σ 0 = 8.9 × 10 2 (ohm-cm) −1 for 160–370°C. The conductivity is compared to earlier work, and several reasons are advanced for considering it to be predominantly ionic. Self-diffusion coefficients for thallium obtained by use of radioactive tracers are much smaller than might be expected from the conductivity on the basis of the Einstein relation. Several tentative explanations for this apparent discrepancy are proposed, and further work is discussed.
A super-aggregation strategy for multi-homed mobile hosts with heterogeneous wireless interfaces

Most mobile devices today are equipped with multiple and heterogeneous wireless interfaces. In this paper we ask the following question: What is the best approach to leverage the multiple interfaces available at a mobile device in terms of the performance delivered to the user? In answering the question we argue that simple "bandwidth aggregation" approaches do not provide any meaningful benefits when the multiple interfaces used have highly disparate bandwidths as is true in many practical environments. We then present super-aggregation, a set of mechanisms that in tandem use the multiple interfaces intelligently and in the process is able to achieve a performance that is "better than the sum of throughputs" achievable through each of the interfaces individually. We prototype super-aggregation on both a laptop and the Google Android mobile phone and demonstrate the significant (up to 3$$\times$$× throughput) performance improvements it provides in real-world experiments. We conduct both theoretical analysis and extensive experiments to show that super-aggregation is able to improve throughput beyond the sum of the parts under most of the cases.
Converging Evidence of NMDA Receptor Hypofunction in the Pathophysiology of Schizophrenia

Numerous clinical studies demonstrate that subanesthetic doses of dissociative anesthetics, which are noncompetitive antagonists at the NMDA receptor, replicate in normal subjects the cognitive impairments, negative symptoms, and brain functional abnormalities of schizophrenia. Postmortem and genetic studies have identified several abnormalities associated with schizophrenia that would interfere with the activation of the glycine modulatory site on the NMDA receptor. Placebo-controlled clinical trials with agents that directly or indirectly activate the glycine modulatory site consistently reduce negative symptoms and frequently improve cognition in patients with chronic schizophrenia who are receiving concurrent typical antipsychotics. Thus, there is convincing evidence that hypofunction of a subset of NMDA receptors may contribute to the symptomatic features of schizophrenia.
Metabolic bone disease after gastrectomy

Abstract An extensive survey revealed a significant biostatistical difference in the incidence of metabolic bone disease when 342 patients who had been treated with various types of partial gastrectomy were compared with a series of 180 patients with peptic ulcer of similar age and sex distribution. Thirty per cent of the postgastrectomy patients and only 5 per cent of the nonsurgical patients had defects in calcium metabolism. On the basis of this survey, postgastrectomy bone disease seems to be more common in the United States than supposed. Osteomalacia appears to be the major bone lesion and may be present in 25 per cent of postgastrectomy patients. Statistical correlation between fecal fat excretion and various calcium abnormalities further suggests that malabsorption is the predominant causative mechanism.
Calcium-dependent binding of calmodulin to neuronal gap junction proteins.

Abstract We examined the interactions of calmodulin with neuronal gap junction proteins connexin35 (Cx35) from perch, its mouse homologue Cx36, and the related perch Cx34.7 using surface plasmon resonance. Calmodulin bound to the C-terminal domains of all three connexins with rapid kinetics in a concentration- and Ca 2+ -dependent manner. Dissociation was also very rapid. K d ’s for calmodulin binding at a high-affinity site ranged from 11 to 72 nM, and K 1/2 ’s for Ca 2+ were between 3 and 5 μM. No binding to the intracellular loops was observed. Binding competition experiments with synthetic peptides mapped the calmodulin binding site to a 10–30 amino acid segment at the beginning of the C-terminal domain of Cx36. The micromolar K 1/2 ’s and rapid on and off rates suggest that this interaction may change dynamically in neurons, and may occur transiently when Ca 2+ is elevated to a level that would occur in the near vicinity of an activated synapse.
Hemorrhagic cystitis inbone marrow transplantation

Objectives Patients undergoing bone marrow transplantation are at risk forhemorrhagic cystitis despite appropriate preventive measures. This complication could have an impact on patient survival and other outcome variables.
A diagnostic taxonomy of adult career problems

Abstract This study focused on the differential diagnosis of adult career development problems. The study was accomplished through four major activities: a literature review of adult career development research, a descriptive analysis of adult career problems, a formulation of alternative taxonomic models, and a pilot validation study. The outcome of this study, a diagnostic taxonomy of adult career problems, is presented below. The taxonomy consists of four major problem categories: (1) problems in career decision making, (2) problems in implementing career plans, (3) problems in organizational/institutional performance, and (4) problems in organizational/institutional adaptation. Category descriptions and examples are also presented.
The impact of population dynamics on public policy: the perspective of political gerontology.

Dramatic increases in the proportion of older persons in the U.S. is an area of profound and direct political and policy impact; not only are there increasing numbers of older persons but the politically relevant characteristics of tomorrows elderly differentiate them from todays and yesterdays elderly. Recent findings are summarized which contradict the view that the aged and the issue of aging are not increasingly salient aspects of politics in the U.S. A brief consideration of the Social Security issue highlights the potential importance of this issue. The changing age structure of the population summarized in the Old-Age Dependency Ratios is seen as more relevant to the possible conflict over policy allocations than is the scenario described by the Total Dependency Ratios. With respect to the cohort concept of age group differences and age-group phenomena the flow of cohorts through the population system represents the succession of potentially unique generational entities whose characteristics and location in the flow of population can substantially influence society and politics. The most explosive policy issue deriving from the changing age structure of the American population surrounds the national Social Security system while operational solutions for predicted Social Security "bankruptcy" might be fiscal or economic in nature the fundamental decisions are derived from political philosophy and political influence. Policy responses to demographic pressure will be a product of political dynamics and the following areas of political inquiry describe the likely foundation of old-age influence upon American politics: 1) political participation; 2) political attitudes; 3) partisan flexibility; and 4) organizational activity. Predictions that population patterns are likely to produce political controversies and that in this context age is likely to grow as a political issue should not be surprising.
Irish-American trade, 1660-1783

List of illustrations List of tables Preface Introduction 1. Trade before 1731 2. Irish-American trade, 1731-1775 3. Balance of payments and financial structure 4. Irish merchants and ports 5. West Indian merchants and ports 6. North American merchants and ports 7. The emigrant trade 8. Provisions 9. Linen 10. Flaxseed 11. Other colonial exports 12. Trade and revolution Conclusion Appendices Notes Bibliography Index.
Single-step generation of fluorophore-encapsulated gold nanoparticle core–shell materials

We report a simple route to produce fluorophore-encapsulated gold nanoparticles (AuNPs) in a single step under aqueous conditions using the fluorophore 1-pyrenemethylamine (PMA). Different amounts of PMA were used and the resulting core-shell gold nanoparticles were analyzed using UV-visible absorption spectroscopy, fluorescence spectroscopy, and transmission and scanning electron microscopy. Electron microscopy analysis shows nanoparticles consisting of a gold nanoparticle core which is encapsulated with a lower contrast shell. In the UV-visible spectra, we observed a significant red shift (37 nm) of the localized surface plasmon resonance (LSPR) absorption maximum (lambda(max)) compared to citrate-stabilized AuNPs of a similar size. We attribute the prominent LSPR wavelength shift for PMA-AuNP conjugates to the increase in the local dielectric environment near the gold nanoparticles due to the shell formation. This simple, aqueous-based synthesis is a new approach to the production of fluorophore-encapsulated AuNPs that could be applicable in biological sensing systems and photonic device fabrication.
Tuning of a cholesteric filter having a negative dielectric anisotropy

We have studied the tunability of the reflection notch of a cholesteric filter containing a negative dielectric anisotropy LC in a planar alignment. For this purpose, we studied physical, optical and electro-optical characteristics of mixtures containing chiral dopant S811 and the negative dielectric anisotropy liquid crystal ZLI-2806. Interestingly, smectic A phases were seen at room temperature for S811 loadings >20% by weight of ZLI-2806. Polarized optical microscopy (POM) and differential scanning calorimetry (DSC) studies confirmed the formation of a cholesteric phase above room temperature. A phase diagram was constructed by varying S811from 9-50% by weight in the mixture. Reflection notchs were not seen at room temperature for compositions of S811 >20%. On heating, the selective reflection notch of the cholesteric phase appeared and blue shifted with temperature. Various methods of tuning the reflection notch were examined. Thermal tuning from 2200 nm to 450 nm was observed over the temperature range 23 to 55° C. Application of a DC field led to electrical tuning (~50 nm) of the notch. The notch was also tuned (>500 nm) optically by exposing a dye doped cholesteric cell to laser lines at either 532 or 647 nm.
Bilayer acyl chain dynamics and lipid-protein interaction: the effect of the M13 bacteriophage coat protein on the decay of the fluorescence anisotropy of parinaric acid.

Nanosecond fluorescence polarization anisotropy decay is used to determine the effect of the bacteriophage M13 coat protein on lipid bilayer acyl chain dynamics and order. The fluorescent acyl chain analogues cis- and trans-parinaric acid were used to determine the rate and extent of the angular motion of acyl chains in liquid crystalline (39 degrees C) dimyristoylphosphatidylcholine bilayers free of coat protein or containing the coat protein at a protein:lipid ratio of 1:30. Subnanosecond time resolution was obtained by using synchrotron radiation as the excitation source for single photon counting detection. Previous measurements of Forster energy transfer from coat protein tryptophan to cis- or trans-parinaric acid have shown that these probes are randomly distributed in the bilayer with respect to the protein. The anisotropy decay observed for pure bilayers has the form of a rapid drop, followed by a nonzero constant region extending from roughly 3 ns to at least 12 ns. The magnitude of the anisotropy in the plateau region is simply related to the acyl chain order parameter. The effect of the M13 coat protein is to increase the acyl chain order parameter significantly while having only a small effect on the rate of angular relaxation. This behavior is rationalized in terms of a simple microscopic model. The order parameters for pure lipid and coat protein containing bilayers are compared to 2H-NMR values.
Fast-switching flexoelectric cholesteric liquid crystal displays

Fast-switching flexoelectric cholesteric liquid crystal displays that can be operated in two modes: amplitude (flexoelectric effect, in-plane-switching) and phase (dielectric coupling, out-of-plane switching) have been developed. The device comprises of a small amount of polymer network localized at the substrate surfaces and short-pitch cholesteric liquid crystal whose helical axis laid in the direction parallel to the substrates. The polymer network stabilizes the helical axis in the plane parallel to the substrates at zero voltage. The response times for amplitude and phase switching of a polymer-stabilized cholesteric display with 2 microns cell gap are 200 μs at 3.5 V/μm and 3 ms at 12.5 V/μm, respectively. Using a dual-frequency switchable nematic liquid crystal, we are able to improve the contrast of the amplitude switching by obtaining a larger deviation angle of helical axis with a high voltage and in the same time, suppressing the helix unwinding.
The extension of numerical solutions of ordinary differential equations

A well known theorem [1] which guarantees the existence of a unique continuous solution for 1) y′ = f(x,y) passing through the point (x0, y0) is:A) Let f (x, y) be continuous and single valued in D where D is the set of points (x, y) such that |x - x0|≤ a, |y - y0|≤b; let M be the maximum of |f(x, y)| on D , and let h = min (a, b/m). If there is a constant k such that for all point pairs (x, y1), (x, y2) in D |f(x, y1) - f(x, y2)| 0 are in general bounded. Since the solution curve y(x) may not be known, under what circumstances is it reasonable to extend the numerical solution? It is the purpose of this paper to define such extension and to give three theorems concerning it.
Nanostructural aspects, free volume and phase constitution of rapidly solidified Nd–Fe–B

Abstract A complement of experimental characterization techniques – positron annihilation spectroscopy (PAS), transmission electron microscopy, synchrotron X-ray diffraction and elevated temperature ac and dc magnetic measurements – were applied to the study of melt-quenched stoichiometric Nd 2 Fe 14 B ribbons modified by various amounts of the alloying additions Ti and C. These alloying additions are known to enhance the glass-forming ability in Nd 2 Fe 14 B melts, allowing for a wider processing window to produce homogeneous nanoscale materials with tailored magnetic properties. The experimental techniques used in this study reveal the complex multi-phase and multi-scale nature of the ribbons, a result that had escaped detection by lower-resolution techniques. The as-quenched ribbons were found to consist of at least three phases: α-Fe nanocrystals, poorly crystalline Nd 2 Fe 14 B and glass. The measured weight fraction of glass does not show a direct correspondence with quenching wheel speed, a result attributed to the complexity of the melt-spinning heat-transfer process. The Curie temperature of the glassy component of the ribbons varies in a non-systematic way with both Ti and C alloying addition content and wheel speed. PAS provides quantitative measurements of the S (or ‘shape’)-parameter which represents the size of a void or open volume in the material volume probed. The experimental results indicate that an excess of free volume in the glass is associated with increased glass stability, a counterintuitive conclusion. However, the results are consistent with the model of Sietsma and Thijsse [Phys. Rev. B 52 (5) (1995) 3248] who propose that thermal relaxation in glass causes the larger free volume regions in the amorphous structure to break up into smaller voids, which necessarily increases the total number of voids, but decreases the volume per void. This void breakup fosters the processes of cooperative diffusion and subsequent devitrification. It is concluded that the free volume concentration in the amorphous component of melt-spun Nd 2 Fe 14 B alloys produced by the highest quenching wheel speeds and Ti/C alloying addition content is thus not sufficient to allow cooperative diffusion to take place, resulting in an increased stability against devitrification.
Amino acid analogs as tools for the study of amino acid metabolism in mammalian cells

Abstract Amino acid analogs can inhibit several steps in the metabolism and/or utilization of the natural amino acids in mammalian cells. Mutants can be selected on the basis of their resistance to these analogs. Such mutants may be altered in their transport of amino acids, in the regulation of amino acid biosynthesis or in the utilization of amino acids for protein synthesis. Analysis of these mutants will help clarify the mechanisms which regulate these various processes.
Particle–solid interactions and 21st century materials science

Abstract The basic physics that governs the interaction of energetic ion beams with solids has its roots in the atomic and nuclear physics of the last century. The central formalism of Jens Lindhard, describing the “particle–solid interaction”, provides a valuable quantitative guide to statistically meaningful quantities such as energy loss, ranges, range straggling, channeling effects, sputtering coefficients, and damage intensity and profiles. Modern materials modification (nanoscience, solid state dynamics) requires atomic scale control of the particle–solid interaction. Two recent experimental examples are discussed: (1) the control of the size distribution of nanocrystals formed in implanted materials and (2) the investigation of the site-specific implantation of hydrogen into silicon. Both cases illustrate unique solid-state configurations, created by ion implantation, that address issues of current materials science interest.
Progresiones de aprendizaje: Promesa y potencial

ABSTRACT (Learning Progressions: Promise and Potential) The educational construct of Learning Progression (LP) is becoming central in research and curriculum development in science education in the US. Learning progressions are models that describe how students’ understanding of central concepts or ideas becomes more sophis­ticated over time. To date, only a few learning progressions have been developed and validated in critical science areas. In this issue of Educacion Quimica , leaders and pioneers in LP re­search and development across the world describe and discuss their efforts to expand and strengthen our understanding of learning progressions in chemistry. KEYWORDS: learning progressions, curricular models, chemistry teaching editorial 1 department of chemistryand biochemistry, university arizona, tuc-son, aZ 85721. correo electronico: vicente@u.arizona.edu* Educacion Quimica agradece a Vicente talanquer por su labor como coor-dinador de la seccion “Areas tematicas emergentes de la educacion quimi-ca [Progresiones de aprendizaje en Quimica]”, desde la definicionde gran parte de los participantes, su seguimiento a lo largo de meses de trabajo intenso, hasta la elaboracion de esta editorial.
The discovery of microorganisms by Robert Hooke and Antoni Van Leeuwenhoek, fellows of the Royal Society.

The existence of microscopic organisms was discovered during the period 1665–83 by two Fellows of The Royal Society, Robert Hooke and Antoni van Leeuwenhoek. In Micrographia (1665), Hooke presented the first published depiction of a microrganism, the microfungus Mucor . Later, Leeuwenhoek observed and described microscopic protozoa and bacteria. These important revelations were made possible by the ingenuity of Hooke and Leeuwenhoek in fabricating and using simple microscopes that magnified objects from about 25–fold to 250–fold. After a lapse of more than 150 years, microscopy became the backbone of our understanding of the roles of microbes in the causation of infectious diseases and the recycling of chemical elements in the biosphere.
Catastrophe forecasting: seeing “gray” among the “black boxes”

Purpose – The purpose of this paper is to consider the problem of using “black‐box” methods to forecast catastrophe events, and illustrate the value of independent peer review.Design/methodology/approach – The problem with black‐box catastrophe forecasts is the absence of both extensive validation data and impartial peer review. These issues may be addressed by comparing black‐box forecasts with a set of naive alternative forecasts provided by an independent party. To illustrate this approach, the historical hurricane forecasts of Dr William M. Gray, professor at Colorado State University, are considered and a simple ARIMA analysis is offered as a naive alternative.Findings – The analysis shows that Dr Gray's complex forecasting methodology does in fact provide reasonable forecasts, and may indeed offer value beyond a naive alternative model.Originality/value – The editorial identifies a major problem in catastrophe forecasting, and suggests one way to address this problem.
ESSCA: A Multidimensional Analysis Tool for Marketing Research

Multidimensional analysis techniques such as ESSCA (External Single-set Components Analysis) are useful for marketing researchers who want to estimate the dimensionality of a group of related measurement instruments. Here, the advantages and disadvantages of this procedure are illustrated through an investigation of four advertising recall measures. The ESSCA solution suggests that two dimensions of recall are actually being measured: favorable recall of stimulus features and brand name recall.
Pediatric Concussion, Cognitive Rest and Position Statements, Practice Parameters, and Clinical Practice Guidelines

There are several organizations that have published statements related to concussion management especially as it relates to cognitive rest. A review of these statements reveals that this issue is more complicated than proposed. Further research is needed to establish (1) the type and severity of concussion symptoms that may benefit from cognitive rest, if any, and the (2) type, degree, and duration of cognitive rest. Parents need to be counseled that definitive recommendations about cognitive rest are not currently based on sufficient research to make specific recommendations for every child with a concussion. This issue has important clinical and medicolegal ramifications to practitioners.
Etanercept: a clinical review of current and emerging indications

The recent development of inhibitors of TNF-alpha has provided the opportunity for a more targeted and highly effective approach to the treatment of chronic inflammatory illnesses such as rheumatoid arthritis. Since the initial approval of etanercept as a treatment for rheumatoid arthritis, additional indications, including psoriatic arthritis, juvenile rheumatoid arthritis and ankylosing spondylitis, have also received FDA approval. More than 220,000 patients have been treated with etanercept so far. This review summarises the body of knowledge accumulated so far on etanercept (Enbrel) since it entered the market 5 years ago.
Galois theory for fuzzy fields

Abstract The aim of this paper is to present a generalized form of the Galois connection between the intermediate fields of a field extension and the subgroups of the corresponding Galois group.We prove that the fundamental theorem of Galois theory accepts a generalization in the fuzzy framework.
A mechanistic simulation analysis of water use, leaf angles, and grazing in East African graminoids

Abstract A simulation model was constructed in order to interrelate the effects of defoliation by large mammalian herbivores with growth, photosynthesis, water use and light interception of representative graminoid vegetation from East Africa. Abiotic submodels describing water flows, light penetration and interception, and energy balance relationships were interfaced with a graminoid growth model that was specifically designed to examine grazing responses. Defoliation reduced rainfall interception and reduced transpiration, thereby increasing soil and plant water levels. Morphological adaptations made compensatory shoot growth possible, but grazing effects on plant water contents largely determined the degree of compensatory growth. Aboveground productivities were greatest at moderate grazing intensities while belowground productivities were greatest at lower grazing intensities. The success of a given water use strategy depended on simultaneous consideration of the abiotic environment and grazing. Under frequent grazing soil water conservation and reduced shoot/root ratio counteracted the depletion effect of high stomatal conductance on plant water content. Consequently photosynthesis under frequent grazing was maximized by higher stomatal conductance. Canopy geometry was adaptive for maximal light harvesting subject to the constraints imposed by transpiration, water availability, and herbivory. Total photosynthesis was increased greatly by erect leaf angles for all but not short grasses. For frequently grazed short-grasses the benefits of prostrate leaves associated with escape from grazing exceeded the associated costs of reduced photosynthate.
Mass measurements of 19Na and 23Al using the (3He, 8Li) reaction☆

Abstract The mass excesses of 19 Na and 23 Al have been measured with the ( 3 He, 8 Li) reaction. The values obtained are 12928 ± 12 keV and 6767 ± 25 keV, respectively. The first excited state of 19 Na, observed to lie at 120 ± 10 keV, completes a mass quartet which agrees with a quadratic isobaric multiplet mass equation.
Catecholaminergic cells and support cell precursors in neural crest cultures differentially express nerve growth factor receptors.

Abstract Long-term neural crest cultures grown in the continuous absence of exogenous nerve growth factor (NGF) contain a subpopulation of cells with NGF receptors exclusively of the low affinity subtype ( d of approximately 3.2 nM). The current studies combined immunocytochemistry, using GIN1 (a support cell marker) or tyrosine hydroxylase antibodies, with radioautography following exposure to iodinated nerve growth factor ( 125 I-NGF). The majority of cells specifically binding 125 I-NGF were found to be immunoreactive for GIN1, indicating that the primary cell phenotype expressing receptors for NGF appear to be support cell precursors, at least under these conditions. These cells are likely to be responsive to and/or dependent upon NGF; the nature of this response or dependency remains to be determined. Some cells exhibiting silver grains were not immunoreactive for GIN 1, suggesting that other cell phenotypes in neural crest cultures also have NGF receptors. In addition, some neural crest cells were found that stained with GIN1 and lacked 125 I-NGF binding. Tyrosine hydroxylase-like immunoreactive cells apparently did not bind 125 1-NGF under these culture conditions. Catecholaminergic sympathetic and sensory neurons from embryonic ganglia, derived from the neural crest, express both the high and low affinity forms of the NGF receptor. In order to determine whether the microenvironment played a role in the type of Catecholaminergic cells appearing in culture, neural crest cells were grown in the continuous presence of exogenous NGF. Under these conditions, many tyrosine hydroxylase-like immunoreactive cells were found that specifically bound 125 I-NGF. In addition, silver grains were still detected on these cells following a chase with nonradioactive NGF, designed to eliminate 125 I-NGF bound to low affinity sites. Therefore, the Catecholaminergic cells possess both the low and high affinity forms of the receptor. NGF's ability to modulate tyrosine hydroxylase activity, as it does in mature Catecholaminergic neurons, was tested in this system. Surprisingly, there was no statistically significant difference in tyrosine hydroxylase activity in cultures grown in the absence or presence of exogenous NGF. This raises the possibility that embryonic Catecholaminergic cells are unable to respond to NGF in this specific way, even though the receptors for the factor are present.
Electrokinetic Assembly of Microsphere and Cellular Arrays

We have developed a novel electrochemical system for field assisted, fluidic assembly of objects on a microfabricated silicon substrate by means of electrical addressing. The principle of our technique is based on the movement of charged species in solution to oppositely charged electrodes, as seen commonly in electrophoresis. Here, charged species such as beads and cells are moved electrokinetically through an aqueous solution towards a charged electrode. Micro patterning of the electrodes allows localization of charged species. We present a theoretical framework to predict the electric potential for assembly and disassembly of spherical objects. We correlate theoretical predictions with the motion of negatively charged polystyrene beads of 20 µm diameter on 100 µm feature micro patterned substrates. In addition, we extended these results to arraying of 20-30 µm diameter live mammalian cells by means of electrical addressing. This technique has applications in creation of ‘active’ cellular arrays for cell biology research, drug discovery and tissue engineering.
Endoplasmic reticulum (ER) stress: hepatitis C virus induces an ER-nucleus signal transduction pathway and activates NF-κB and STAT-3

Human hepatitis C virus (HCV) is the leading cause of chronic hepatitis, which often results in liver cirrhosis and hepatocellular carcinoma. The HCV RNA genome codes for at least ten proteins. The HCV non-structural protein 5A (NS5A) has generated considerable interest due to its effect on interferon sensitivity via binding and inactivating the cellular protein kinase, PKR. It has been shown that NS5A engages in the endoplasmic reticulum (ER)-nucleus signal transduction pathway. The expression of NS5A in the ER induces an ER stress ultimately leading to the activation of STAT-3 and NF-kappaB. This pathway is sensitive to inhibitors of Ca(2+) uptake in the mitochondria (ruthenium red), Ca(2+) chelators (TMB-8, EGTA-AM), and antioxidants (PDTC, NAC, Mn-SOD). The inhibitory effect of protein tyrosine kinase (PTK) inhibitors indicates the involvement of PTK in NF-kappaB activation by NS5A. This implicates an alternate pathway of NF-kappaB activation by NS5A. The actions of NS5A have also been studied in the context of an HCV subgenomic replicon inducing a similar intracellular event. Thus, activation of NF-kappaB leads to the induction of cellular genes, which are largely antiapoptotic in function. These studies suggest a potential function of NS5A in inducing chronic liver disease and hepatocellular carcinoma associated with HCV infection.
Improving processor efficiency by statically pipelining instructions

A new generation of applications requires reduced power consumption without sacrificing performance. Instruction pipelining is commonly used to meet application performance requirements, but some implementation aspects of pipelining are inefficient with respect to energy usage. We propose static pipelining as a new instruction set architecture to enable more efficient instruction flow through the pipeline, which is accomplished by exposing the pipeline structure to the compiler. While this approach simplifies hardware pipeline requirements, significant modifications to the compiler are required. This paper describes the code generation and compiler optimizations we implemented to exploit the features of this architecture. We show that we can achieve performance and code size improvements despite a very low-level instruction representation. We also demonstrate that static pipelining of instructions reduces energy usage by simplifying hardware, avoiding many unnecessary operations, and allowing the compiler to perform optimizations that are not possible on traditional architectures.
Increased recombinant activated factor VII use and need for surgical reexploration following a switch from aprotinin to epsilon-aminocaproic acid in infant cardiac surgery.

Abstract Study Objective To evaluate whether conversion from aprotinin to epsilon-aminocaproic acid (EACA) during infant cardiac surgery was associated with increased perioperative bleeding. Design Structured retrospective chart review. Setting University-affiliated large congenital cardiac surgery program. Measurements Records from 145 infants (age Main Results EACA treated patients received significantly more rFVIIa for uncontrolled bleeding (19/77 [25%] vs 3/68 [4%]; P P = 0.01]. Median (25th-75th percentiles) intraoperative platelet transfusion requirements were also increased after the switch to EACA (28 mL [0-58 mL] vs 0 mL [0 mL - 34.5 mL]), but this difference did not reach statistical significance ( P = 0.06). Conclusions Bleeding in infant cardiac surgery increased following the change in antifibrinolytic therapy from aprotinin to EACA. Given the potential for major harm, especially thrombotic complications, from rFVIIa use, prospective studies examining the safety of postcardiopulmonary bypass rFVIIa administration in infants are necessary before the routine off-label use may be recommended.
Choosing Violence in Irregular Wars The Case of Anti-Soviet Insurgency in Western Ukraine

Do warring sides in asymmetric conflicts always know what type of violence they use against civilians? This article relies on the case study of an anti-Soviet insurgency in Western Ukraine between ...
Modelling hearing thresholds in the elderly

This paper concerns a linear mixed-effects repeated measures model in the analysis of a large data set with over 17,000 observations in a longitudinal study of pure-tone hearing perception in the elderly. The repeated measurements are described by fixed and random components in the model. The fixed effects include the age at entry, time of follow-up, a quadratic component in natural logarithm of frequency, a component to allow for participants with hearing impairments, as well as interaction terms between age and frequency and between impairment and frequency. The random factors include a term for subject, a time component and a frequency component. The analysis shows that hearing impaired individuals have similar patterns of hearing loss over time but, on average, have higher hearing thresholds than normal individuals. Estimation of the random effects in the model by restricted maximum likelihood (REML) using the Newton-Raphson method made possible the analysis of this large data set with speed and efficiency.