cssi/SciSciGPT-SciSciNet huggingface dataset:
Progress on Nonlinear Optical Chromophores and Polymers with Useful Nonlinearity and Thermal Stability

Organic nonlinear optical (NLO) polymers must possess large and stable bulk nonlinear properties if they are to be of practical use. Numerous classes of NLO chromophores and polymers have already been evaluated but the selection process, particularly as related to stability issues, has been very stochastic in nature. If suitable chromophores are to be successfully identified their thermochemical degradation Mechanisms Must be elucidated and structural modifications introduced in a rational fashion. We have devised a protocol for the evaluation of NLO chromophores which involves initial screening by thermal analysis (DSC and TGA) and selected molecular hyperpolarizability (EFISH) analysis. The Most promising candidates are incorporated into thermoplastic polymer hosts where bulk nonlinear properties (d ij and r ij ) and additional thermal stability properties are evaluated by spectroscopie Means (UV-VIS). Cyclicvoltammetry (CV) has been identified as a useful tool for evaluation of these chromophores; in the case of azobenzenes with aliphatic amine donor and a nitro acceptor a correlation between the thermal stability and oxidation potential has been found. The Most facile thermal degradation mechanism which occurs in these dyes has been identified and structural changes to the donor group have been introduced to avert the process.
Evaluation of the supraspinal analgesic activity and abuse liability of ethylketocyclazocine

Abstract Rats were trained to escape from aversive electrical brain stimulation delivered to the midbrain reticular formation (MRF) or to obtain rewarding intracranial stimulation delivered to the medial forebrain bundle (MFB). The threshold for escape behavior was determined by a modification of the psychophysical method of limits. Likewise, reward thresholds were determined by a rate-free psychophysical method. Acute administration of ethylketocyclazocine (EKC) (0.06–1.0 mg/kg s.c.) raised escape threshold in a dose-dependent manner while having no effect on non-specific measures of sedation or motor impairment. This suggests that opioids with κ receptor activity specifically modulate pain at a supraspinal level. Administration of EKC had no effect on the threshold for rewarding intracranial stimulation to the MFB suggesting that EKC has low potential for abuse.
Effect of a Metastable Precipitate on the Electrical Properties of an Li2,O-SiO2 Glass

Glass structural differences in a 17.5 wt% (30 mole %) Li2O-SiO2 glass resulting from thermal treatments in the annealing-transformation range were studied using electron microscopy, X-ray analysis, and dc and ac electrical properties. Metastable, crystalline lithium metasilicate precipitates and subsequently redissolves prior to the appearance of the equilibrium lithium disilicate crystals. The lithium metasilicate gives rise to dielectric loss peaks in the 100 hz to 1 Mhz range which can be rationalized on the basis of the Maxwell-Wagner-Sillars heterogeneous dielectric model.
An efficient nonparametric test for bivariate two-sample location problem

Abstract We propose a new test for the two-sample bivariate location problem. The proposed test statistic has a U -statistic representation with a degenerate kernel. The limiting distribution is found for the proposed test statistic. The power of the test is compared using Monte Carlo simulation to the tests of Blumen [I. Blumen, A new bivariate sign-test for location, Journal of the American Statistical Association 53 (1958) 448–456], Mardia [K.V. Mardia, A non-parametric test for the bivariate two-sample location problem, Journal of the Royal Statistical Society, Series B 29 (1967) 320–342], Peters and Randles [D. Peters, R.H. Randles, A bivariate signed-rank test for the two-sample location problem, Journal of the Royal Statistical Society, Series B 53 (1991) 493–504], LaRocque, Tardif and van Eeden [D. LaRocque, S. Tardif, C. van Eeden, An affine-invariant generalization of the Wilcoxon signed-rank test for the bivariate location problem, Australian and New Zealand Journal of Statistics 45 (2003) 153–165], and Baringhaus and Franz [L. Baringhaus, C. Franz, On a new multivariate two-sample test, Journal of Multivariate Analysis 88 (2004) 190–206]. Under the bivariate normal and bivariate t distributions the proposed test was more powerful than the competitors for almost every change in location. Under the other distributions the proposed test reached the desired power of one at a faster rate than the other tests in the simulation study. Application of the test is presented using bivariate data from a synthetic and a real-life data set.
An unusual rearrangement during pyridine synthesis. Anomalous condensation of a β-keto enamine with a tetronic acid

Abstract The condensation of β-keto enamine 1 with 5-methyltetronic acid takes an anomalous course. Single crystal X-ray analysis and chemical evidence establish the rearranged pyridine structure 15 for this condensation product.
Experimental demonstration of an analytic method for image reconstruction in optical diffusion tomography with large data sets.

We report the first experimental test of an analytic image reconstruction algorithm for optical tomography with large data sets. Using a continuous-wave optical tomography system with 108 source–detector pairs, we demonstrate the reconstruction of an absorption image of a phantom consisting of a highly scattering medium containing absorbing inhomogeneities.
Flexibility of single microvilli on live neutrophils and lymphocytes.

We measured the flexural stiffness of single microvilli on live human neutrophils and lymphocytes using 40-nm fluorescent beads. The beads were bound to the tips of the microvilli by anti-$L$-selectin antibodies. Digital bead images were acquired with an exposure time of $3\phantom{\rule{0.3em}{0ex}}\mathrm{s}$ at high magnification. Using a Gaussian point spread function, we obtained an analytical expression that relates the image profile to the flexural stiffness. We found that the flexural stiffnesses were 7 and $4\phantom{\rule{0.3em}{0ex}}\mathrm{pN}∕\mathrm{\ensuremath{\mu}}\mathrm{m}$ for single microvilli on human neutrophils and lymphocytes, respectively. We also verified with live cells that 75% of neutrophil $L$-selectin and 72% of lymphocyte $L$-selectin were on the microvillus tips. Our results indicate that the leukocyte microvilli in contact with the endothelium or other surfaces will bend easily under physiological shear stresses.
Changes in Sin Nombre Virus Antibody Prevalence in Deer Mice Across Seasons: The Interaction Between Habitat, Sex, and Infection in Deer Mice

We examined the impact of season and habitat on Sin Nombre virus (SNV) seroprevalence in deer mice (Peromyscus maniculatus) in Utah's Great Basin Desert from May 2002 through summer 2003. Low mouse captures in 2002 limited analysis for that year. In two seasons during 2003, mouse density and sagebrush cover were positively linked (spring: r=0.8, P=0.01; summer: r=0.8, P=0.04). In the spring, seroprevalence was negatively correlated with density (r=−0.9, P<0.01); male and female antibody prevalence did not differ; and scarring was unrelated to antibody status. In the summer, density and antibody prevalence were unrelated; male seroprevalence was higher (χ2=3.6, P=0.05); and seropositive mice had more scars (t=2.5, P=0.02). We speculate nesting behavior could maintain SNV over the winter, whereas summer territoriality could be responsible for transmission.
Maturational Constraints on Language Learning

This paper suggests that there are constraints on learning required to explain the acquisition of language, in particular, mului ultonol constraints. First, empirical evidence for this daim is reviewed. The evidence from several studies of both first and second languoge acquisition suggests that normal language learning occurs only when exposure to the languoge begins early in life. With exposure beginning later in life, asymptotic performance in the language declines: the effects over oge of first exposure are approximately linear through childhood, with a flattening of the function in adulthood. These outcomes argue that some type of constraints ensuring successful languoge learning exist early in life, and weaken with increasing maturation. Second, two hypotheses are considered as to the nature of these maturational changes. One hypothesis is that constraints on learning particular to languoge acquisition undergo maturational decay. A second hypothesis, which is considered in more detail, suggests that language learning abilities decline because of the expansion of nonlinguisftc cognitive abilities.
Apparent anomalous behavior of the power spectrum of 1/f noise and its explanation

The explanation is given for the apparent anomalous behavior of the power spectrum of 1/f noise as if it corresponded to the total infinite power of noise sources. Physical mechanisms eliminating the apparent anomalies are described. With these mechanisms, the finite and integrable 1/f-noise power spectra fitting the known physical concepts of noise processes are obtained in the low-and high-frequency limits.
Incontinence: The role of ambulatory urodynamics in spinal cord injury

Bladder management is an important aspect of the management of patients with spinal cord injury (SCI). A device capable of performing ambulatory urodynamics on individuals with SCI has recently been developed; however, the benefit of ambulatory urodynamics in patients with SCI is disputed.
Heme Reversibly Damps PERIOD2 Rhythms in Mouse Suprachiasmatic Nucleus Explants

The hypothalamic suprachiasmatic nucleus (SCN), which in mammals serves as the master circadian pacemaker by synchronizing autonomous clocks in peripheral tissues, is composed of coupled single-cell oscillators that are driven by interlocking positive/negative transcriptional/translational feedback loops. Several studies have suggested that heme, a common prosthetic group that is synthesized and degraded in a circadian manner in the SCN, may modulate the function of several feedback loop components, including the REV-ERB nuclear receptors and PERIOD2 (PER2). We found that ferric heme (hemin, 3-100 microM) dose-dependently and reversibly damped luminescence rhythms in SCN explants from mice expressing a PER2::LUCIFERASE (PER2::LUC) fusion protein. Inhibitors of heme oxygenases (HOs, which degrade heme to biliverdin, carbon monoxide, and iron) mimicked heme's effects on PER2 rhythms. In contrast, heme and HO inhibition did not damp luminescence rhythms in thymus and esophagus explants and had only a small effect on PER2::LUC damping in spleen explants, suggesting that heme's effects are tissue-specific. Analysis of the effects of heme's degradation products on SCN PER2::LUC rhythms indicated that they probably were not responsible for heme's effects on rhythms. The heme synthesis inhibitor N-methylprotoporphyrinIX (NMP) lengthened the circadian period of SCN PER2::LUC rhythms by about an hour. These data are consistent with an important role for heme in the circadian system.
Block rigid almost completely decomposable groups and lattices over multiple pullback rings

Abstract Category equivalences from subgroups of finite index in finite direct sums of torsion-free abelian groups of rank 1 to finitely generated lattices over special multiple pullback rings are given. Various examples demonstrate the relevance of representations of finite partially ordered sets over factor rings of the integers to both subjects.
Cultural Relevance of Adult Attachment Rasch Modeling of the Revised Experiences in Close Relationships in a Korean Sample

This study examined the cultural relevance of adult attachment within a Korean sample (N = 390) using Rasch rating scale modeling. The psychometric properties of scores from the Korean version of the Revised Experiences in Close Relationships, comprised of two subscales of Anxiety (self) and Avoidance (other), were assessed. Results obtained from separate analyses on each subscale showed that (a) most items measured one common construct, either anxiety or avoidance; (b) each subscale had high estimates of both person and item separation indices; and (c) the items measuring high levels of anxiety and avoidance may not be appropriate for the sample of Korean college students.
Fast Fourier Transforms for Nonequispaced Data, II

Abstract A group of algorithms generalizing the fast Fourier transform to the case of noninteger frequencies and nonequispaced nodes on the interval [-π, π] is presented. The schemes of this paper are based on a combination of the classical fast Fourier transform with a version of the fast multipole method, and generalize both the forward and backward FFTs. Each of the algorithms requires O(N · logN + N · log(l/ϵ)) arithmetic operations, where ϵ is the precision of computations and N is the number of nodes; the CPU time requirement of the method is independent of the distribution of the nodes. The efficiency of the scheme is illustrated by several numerical examples. The approach of this paper is compared to the approach taken by Dutt et al. ("Fast Algorithms for Polynomial Interpolation, Integration, and Differentiation," Tech. Rep. 977, Department of Computer Science, Yale University, 1993) to the same set of problems. It turns out that the scheme of Dutt et al. is preferable for the forward problem, while the method introduced here is considerably more efficient for the inverse one.
NPHP3 mutations are associated with neonatal onset multiorgan polycystic disease in two siblings

Two siblings with a severe multiorgan polycystic disease presenting in the neonatal period were identified. Their genetic testing identified compound heterozygous NPHP3 gene mutations, parents being heterozygous carriers. The mutations included a splice-site (c.958-2A>G) and a missense mutation (c.2342G>A; p.G781D), both being extremely rare. NPHP3 encodes for nephrocystin 3 present on the cilia-centrosome complex. We hypothesize that these mutations lead to defective cilia-based signaling, required for normal development of the renal, pancreatic, biliary and portal system. This report outlines a rare neonatal ciliopathy presentation of NPHP3 mutations leading to severe multiorgan failure in two siblings.
Post-lens tear-film depletion due to evaporative dehydration of a soft contact lens

Abstract For a soft-contact-lens (SCL) wearer, corneal health and comfort are strongly influenced by water transport through the polymeric materials used in lens fabrication. In particular, evaporative water loss at the anterior lens surface is a potential cause of contact-lens dehydration and of post-lens tear-film depletion, which in turn, may lead to discomfort, dryness syndrome, and/or lens adhesion. We present a solution–diffusion model for transport of water through soft-contact-lens materials to mimic evaporative dehydration from a contact lens during blinking and to access possible SCL adhesion to the corneal surface under a variety of environmental conditions (e.g., wind speed and relative humidity). To describe the water-transport process, we use an extended version of the Maxwell–Stefan multicomponent diffusion equation for species that differ starkly in size (i.e., water and the polymer matrix). To describe thermodynamic properties of the soft-contact-lens/water mixture, we use a modified Flory–Rehner theory for polymer solutions. The proposed transport model is applied to two typical SCL materials: a low-water-content (38 wt.%) polymacon SCL (SofLens® 38), and a high-water-content (70 wt.%) hilafilcon A SCL (SofLens™ One Day). We calculate that a SCL on the eye loses water within a few minutes from lens insertion until it reaches a periodic steady state, with an average water content a few percent lower than the initial saturated water content. When the external relative humidity is low and the wind speed is high, the periodic-steady net flux of water from the post-lens tear film (PoLTF) through the contact lens toward the environment is comparable to the supply of water to the PoLTF from the eye anterior chamber. Thus, PoLTF depletion may occur at these conditions, leading to undesired, reduced SCL on-eye movement or, perhaps, to SCL adhesion on the ocular surface. Also, our calculations show that, at the most dehydrating conditions, the high-water-content hilafilcon A lens is more prone to dehydration and PoLTF depletion than is the low-water-content polymacon lens with the same thickness. However, at the least dehydrating conditions this trend is reversed. Relative humidity, wind speed, and lens thickness significantly influence SCL dehydration.
Interpolation by holomorphic automorphisms and embeddings in Cn

Let n > 1 and let C n denote the complex n-dimensional Euclidean space. We prove several jet-interpolation results for nowhere degenerate entire mappings F:C n →C n and for holomorphic automorphisms of C n on discrete subsets of C n.We also prove an interpolation theorem for proper holomorphic embeddings of Stein manifolds into C n.For each closed complex submanifold (or subvariety) M ⊂ C n of complex dimension m < n we construct a domain Ω ⊂C n containing M and a biholomorphic map F: Ω → C n onto C n with J F ≡ 1such that F(M) intersects the image of any nondegenerate entire map G:C n−m →C n at infinitely many points. If m = n − 1, we construct F as above such that C n ∖F(M) is hyperbolic. In particular, for each m ≥ 1we construct proper holomorphic embeddings F:C m →C m−1 such that the complement C m+1 ∖F(C m )is hyperbolic.
When is arithmetic possible

Abstract When a structure or class of structures admits an unbounded induction, we can do arithmetic on the stages of that induction: if only bounded inductions are admitted, then clearly each inductively definable relation can be defined using a finite explicit expression. Is the converse true? We examine evidence that the converse is true, in positive elementary induction (where explicit = elementary). We present a stronger conjecture involving the language L consisting of all L ∞ω formulas with a finite number of variables, and examine a combinatorial property equivalent to “all L -definable relations are elementary”.
Noninvasive characterization of anterior segment structures using real-time optical coherence tomography at 1310 nm

Real-time optical coherence tomography (OCT) was used to visualize and quantify structures in the anterior segment of the eye. Current results of ongoing clinical trials are presented. Preliminary data indicates strong potential for the use of real time OCT as a tool for noninvasive characterization of the anterior chamber angle and for anterior segment biometry.
Ca2+, within the physiological concentrations, selectively accelerates Aβ42 fibril formation and not Aβ40 in vitro

Alzheimer's disease (AD) in humans is a common progressive neurodegenerative disease, associated with cognitive dysfunction, memory loss and neuronal loss. Alzheimer peptides Abeta40 and Abeta42 are precursors of the amyloid fibers that accumulate in the brain of patients. These peptides misfold and the monomers aggregate to neurotoxic oligomers and fibrils. Thus, the aggregation kinetics of these peptides is central to understanding the etiology of AD. Using size exclusion chromatography as well as filtration methods, we report here that Ca(2+) ions at physiological concentrations greatly accelerate the rate of aggregation of Abeta42 to form intermediate soluble associated species and fibrils. In the presence of 1 or 2 mM Ca(2+), CD spectra indicated that the secondary structure of Abeta42 changed from an unfolded to a predominantly beta-sheet conformation. These concentrations of Ca(2+) greatly decreased the lag time for Abeta42 fibril formation, measured with thioflavin T. However, the elongation rate was apparently unaffected. Ca(2+) appears to predominantly accelerate the nucleation stage of Abeta42 on pathway to the Alzheimer's fibril formation. Unlike Abeta42, Ca(2+) was not observed to trigger similar effect at any stage during the study of fibrillation kinetics of Abeta40 by any techniques. Abeta40 and Abeta42 seem to have distinct aggregation pathways.
Statistics and environmental regulations

Statistics has historically played a role in studying the environment. Statistics has been used in determining the presence and amount of pollution of several types as well as studying the spread and health effects of pollution. More recently the role of statistics in environmental regulation has been explicitly recognized with new regulations requiring statistical approaches to study design, data collection and analysis, and monitoring programs of various types. Two disparate approaches to statistics in regulations have been taken: performance based regulations and method based regulations. Examples of each are discussed, together with the advantages and disadvantages of each approach. The interactions among statisticians, regulators, industry, and communities involved in environmental regulations are discussed.
IMUnit: improved multithreaded unit testing

This position paper argues for an approach to bring several techniques successful for (regression) testing of sequential code over to multithreaded code. Multithreaded code is getting increasingly important but remains extremely hard to develop and test. Most recent research on testing multithreaded code focuses solely on finding bugs in one given version of code. While there are many promising results, the tools are fairly slow (as they, conceptually, explore a large number of schedules) and do not exploit the fact that code evolves over several versions during development and maintenance.Our proposal is to allow explicit specification of relevant schedules (either manually written or automatically generated) for multithreaded tests, which can substantially speed up testing, especially for evolving code. To enable the use of schedules, we propose to design a novel language for specifying schedules in multithreaded tests, and to develop tools for automatic generation of multithreaded tests and for improved regression testing with multithreaded tests.
Neurosurgery in the pre-European era in Australia

Trephination was widely recognised as an achievement of many primitive cultures but until Dr Stephen Webb identified two Australian Aboriginal skulls it was not believed to have occurred on the continent of Australia. The technique and actual instruments used in New Britain for trephination are examined and the two skulls discovered by Dr Webb are presented.
Effects of acute and chronic acidification on three larval amphibians that breed in temporary ponds.

This study explored the effects of acute (7 days) and chronic (4 months) exposure to pH 4.2 on three species of larval amphibians, Ambystoma jeffersonianum, Ambystoma maculatum, and Rana sylvatica. Acute tests were conducted in 24 impermeable enclosures in three temporary ponds. Total dissolved aluminum was higher in acidified enclosures in comparison with controls (pH 4.2, [Al]≈10–30 μM and pH>4.7, [Al]≈5–15 μM, respectively). Greater mortality of A. jeffersonianum occurred at pH 4.2 than at pH>4.7, whereas survival of A. maculatum and R. sylvatica were unaffected by pH. Mean wet masses of R. sylvatica were significantly lower at pH 4.2 than at pH>4.7, but mean wet masses of surviving A. jeffersonianum and A. maculatum were not influenced by pH. There were no pH-related differences in body sodium concentration in larval R. sylvatica.
Beyond climate finance: from accountability to productivity in addressing the climate challenge

Climate finance has been the dominant instrument and narrative with which the international community has approached the challenge of climate change. In particular, it has become the main way in wh...
T Cells, the MHC, and Function

The model presented relates the class of MHC molecule recognized with the activity of T lymphocytes. This occurs by postulating that the function of MHC molecules is to present determinants to differentiation directing (D) receptors on T lymphocytes. These D receptors are distributed nonclonally and interact with nonpolymorphic determinants on MHC molecules which are normally inaccessible. The result of this interaction is to allow for the expression of a functional phenotype for the T cell providing that helper signals are present. In the case of alloreactive CTL that recognize class II or Th that recognize class I molecules we postulate that these T cells require the presence of class I or class II molecules, respectively, on the target cell. Recognition of antigen in the absence of helper signals leads to tolerance of both Th.P and CTL.P. Since helper signals are required for the activation of CTL.P, a lack of specific Th, determined by class II alleles, will prevent development of a proportion of the CTL repertoire.
Linoleic- and linolenic acid dependency of some brain membrane-bound enzymes after lipid deprivation in rats.

Summary Brain monoamine oxidase and 5′-mononucleotidase activities were decreased to 57.0% and 37.6% of control values respectively in rats after a four month period of lipid deprivation. Glucose-6-phosphatase activity increased. On refeeding with either linoleic or linolenic acids, glucose-6-phosphatase values decreased to 35.3% and 58.7% of normal activity respectively, while monoamine oxidase levels returned to normal. However, only linolenic acid was effective in restoring 5′-mononucleotidase activities to normal while linoleic acid produced no change from the deficient values. The results would indicate that linolenic acid may have a biochemical function distinct from linoleic acid in 5′-mononucleotidase metabolism.
Monoclonal anti-(T,G)-A--L antibodies: characterization of fine specificity and idiotype expression.

Abstract The technique of polyethylene glycol mediated cell fusion was used to establish 22 monoclonal cell lines secreting anti-(T,G)-A—L antibody. Cell lines were derived from C3H.SW and B10 mice and produced antibody with k light chains and predominantly γ1, heavy chains. Fine-specificity analysis demonstrated that 15 cell lines made antibodies that also recognize a determinant present on GAT, GT (9:1) and GT (1:1), whereas little, if any, serum antibody demonstrates this cross-reaction. Fourteen antibodies, derived from both B10 and C3H.SW mice, bear idiotypic determinants defined by Lewis anti-[B10 anti-(T,G)-A—L], but only two, both from C3H.SW mice, react with Lewis anti-[C3H.SW anti-(T,G)-A—L]. Adsorption studies indicate that no hybridoma tested bore the complete set of idiotypic determinants defined by either serum.
Preparing the Next Generation in Academic Medicine: Recruiting and Retaining the Best

In many ways, we are living and working in an unprecedented time in academic medicine. New technologies, scientific discovery, unparalleled availability of medical information and knowledge are currently paired with increasing (albeit slow) gender, cultural, and now generational diversity of the faculty. To prepare the next generation, we must simultaneously be the student and the teacher. As the student, our charge is to understand the current medical and academic environs and recognize the attributes, experiences, and expectations that each generational cohort brings to medicine. As the teacher, we must identify, extract, and communicate the tenets that remain constants for success in academic medicine today and reject those that are no longer relevant. Throughout the years, the basic motivation that drives success has remained constant while the individuals (the players), the environment, and the definition of success in academics have become more varied.
Effect of yohimbine on nerve growth factor mRNA and protein levels in rat hippocampus

Abstract Activation of noradrenergic receptors has been shown to increase expression of nerve growth factor (NGF) gene in brain cells in vitro. The present studies were undertaken to determine if this stimulation was effective in vivo as well. Rats were administered the norepinephrine-releasing drug. yohimbine (YOH), and had their hippocampi assayed for NGF mRNA and protein at various times after the injection. It was found that yohimbine caused a 3-fold increase of NGF mRNA levels at 24 h. Protein levels, however, were unaltered at this time. Thus norepinephrine release in vivo appears to be sufficient for increasing mRNA level but not for translation to protein.
Impurity dependence of phonon-assisted tunneling in n-Ge

Abstract Phonon-assisted tunneling was investigated in n -Ge metal-semiconductor junctions as a function of impurity concentration in the semiconductor. The contributions to the conductance due to the LA, TA, LO and TO phonons were measured and the relative contribution of LA to TA and LA to TO phonons was found to depend on impurity concentration. This is in disagreement with the theory based on the ‘second order process’ and indicates that other processes should also be considered.
Studies on the mechanism of action of prekinamycin, a member of the diazoparaquinone family of natural products: evidence for both sp2 radical and orthoquinonemethide intermediates.

The putative reductive activation chemistry of the diazoparaquinone antibiotics was modeled with Bu3Sn−H and prekinamycin dimethyl ether along with prekinamycin itself. Reaction in various combinations of aromatic solvents, with and without the nucleophile benzylmercaptan present, led to isolation of both radical-trapping arene adducts and nucleophilic capture benzyl thioether products. On the basis of these product distribution studies, the intermediacies of, first, a cyclopentenyl radical and, next, an orthoquinonemethide electrophile are postulated.
SINGLE-WALLED CARBON NANOTUBES: APPLICATIONS IN HIGH FREQUENCY ELECTRONICS

In this paper, we review the potential applications of single-walled carbon nanotubes in three areas: passives (interconnects), actives (transistors), and antennas. In the area of actives, potential applications include transistors for RF and microwave amplifiers, mixers, detectors, and filters. We review the experimental state of the art, and present the theoretical predictions (where available) for ultimate device performance. In addition, we discuss fundamental parameters such as dc resistance as a function of length for individual, single-walled carbon nanotubes.
Continuous isotopic x-irradiation of human lung cancer in histoculture

Abstract This is the first report of a method developed for continuous irradiation and simultaneous monitoring by time lapse cinemicrophotography of human lung cancer cells in a histoculture form. A beam of low energy photons at low dose rate produced by a miniature isotopic source was used to irradiate asynchronously proliferating cells. Film records of control cultures over a period of 159 days, and a culture irradiated over a period of 16 days after a baseline pre-irradiation filming of 53 days, yielded 46 irradiated cells and 84 control cells suitable for "metaphase plate time" ( Δt m ) determinations. Anaylsis of the measured Δt m distribution demonstrated a "normal" karyokinesis time in the control culture and accentuation of a slowly dividing subpopulation in the irradiated culture. This increase in ( Δt m ) appeared to results from lower radiation doses and dose rates than have been found to delay other phases of the mammalian cell cycle; a 5-fold prolongation of ( Δt m ) was recorded for half of the mitoses in the irradiated cell culture within the first nine days of irradiation after a total dose of less than 35 rad. The observations suggest that the duration of metaphase may be an especially sensitive indicator of cellular response to irradiation. While the findings are clearly preliminary, the feasibility of the methodology for studying radiation and other challenges to cancer histocultures has been strongly established. The potential clinical significance is especially noteworthy since data recording begins immediately after explantation and deals with cancer in a form close to the in vivo status.
Testing the effect of blocking in a randomized complete block design (RCBD)

In the RCBD, the block system causes, for most applications, strong correlation between responses from experimental units in the same block. Therefore, the usual model with the usual assumptions about zi j. (i.i.d. N(0,σ2)) is not realistic. In this paper we study the consequences of more realistic assumptions about zi j. and verify that the usual F test, for testing treatment effects, can be used even if there is a constant covariance between responses from experimental units in the same block. When the variances associated with each treatment are not the same we give an approximate solution for testing treatment effects.
PRESENTISM, TRUTHMAKERS, AND GOD

The truthmaker objection to presentism (the view that only what exists now exists simpliciter) is that it lacks sufficient metaphysical resources to ground truths about the past. In this paper I identify five constraints that an adequate presentist response must satisfy. In light of these constraints, I examine and reject responses by Bigelow, Keller, Crisp, and Bourne. Consideration of how these responses fail, however, points toward a proposal that works; one that posits God's memories as truthmakers for truths about the past. I conclude that presentists have, in the truthmaker objection, considerable incentive to endorse theism.
Computer analysis of dynamic scenes containing curvilinear figures

Abstract A brief introduction to dynamic scene analysis is given, followed by a description of a system which analyzes sequences of images of moving figures. The methods used to describe the boundaries of the figures, to match common shapes between paired images, and then to analyze the motion of matched figures, are discussed in detail. Finally, a complete example is presented along with some directions for further research.
Age and changes in work: Causes and contrasts

As authors Marshall and Marshall write, company-based human resources policies may be influenced by many factors, such as changing demographics, global economic changes, technological change, and ideologies governing corporate restructuring. Alternatively, these factors may have little direct influence on policy at the company level. In this article, five Canadian case studies, two of them matched in the United States, are drawn upon to investigate company policies influencing the lives of older workers and factors associated with exit from employment. The cases cover the following sectors: the insurance industry, the garment industry, steel manufacturing, telecommunications, gas transmission and petrochemical manufacturing. Formal policy attention to demographic change or the ageing workforce was rare in the companies studied. However, company policies adopted for a variety of reasons had important consequences for their older workers and for age relations in the company. The fact or threat of corporate downsizing pervaded most work contexts, but different approaches taken by the companies had distinct outcomes for working life and the subsequent demographic structure of the firm. While demographic, technological, or economic factors can have important influences on company policies affecting older workers, none of these factors is highly deterministic in its effects. Policy decisions at the company level take these factors into account in widely differing ways.
An alternative mechanism for the nitrogen transfer reaction in asparagine synthetase

In the absence of crystallographic data, the mechanism of nitrogen transfer from glutamine in asparagine synthetase (AS) remains under active investigation. Surprisingly, the glutamine-dependent AS from Escherichia coli (AsnB) appears to lack a conserved histidine residue, necessary for nitrogen transfer if the reaction proceeds by the accepted pathway in other glutamine amidotransferases, but retains ability to synthesize asparagine. We propose an alternative mechanism for nitrogen transfer in AsnB which obviates the requirement for participation of histidine in this step. Our hypothesis may also be more generally applicable to other glutamine-dependent amidotransferases.
Out-of-hospital automatic cardioversion of ventricular tachycardia

A 42 year old man who survived sudden cardiac death was treated with an automatic implantable cardioverter/defibrillator. After a 5 month symptom-free interval, the patient received two internal discharges in the conscious state while wearing an ambulatory electrocardiographic recorder. Analysis of the tape revealed that both discharges were activated by two bursts of polymorphous ventricular tachycardia, the first one occurring at the end and the second at the onset of episodes of slow, hemodynamically stable monomorphous ventricular tachycardia. This case illustrates the reliability of the automatic implantable cardioverter/defibrillator as an antiventricular tachycardia device and the problem posed by its exposure to nonsustained ventricular tachycardia.
Advanced Heart Failure Therapy in HIV Positive Patients: Do These Patients Get Equal Treatment?

Purpose More than 1 million Americans are currently infected with HIV. This study investigates the position of transplant centers towards advanced heart failure (HF) therapy in HIV+ pts. Methods and Materials A survey concerning heart transplant (HT) and LVAD implantation protocol and outcome in HIV+ pts was distributed to all American HT centers (103 in US, 8 in Canada). Results 79% (n=81) of US and 100% (n=8) of Canadian centers (100%) responded. A total of 18 HTs were performed in HIV+ pts with excellent outcome (1,3,10 years survival of 100%, 90%, 63%). 92% (n=82) of the centers never performed HT in HIV+ pts and 57% (n=51) marked HIV+ as a contraindication. The predominant rationales provided were: 1) high-risk pts should be avoided given the scarcity of organ supply (59%), 2) Immunosuppression required for HT may induce HIV progression to AIDS (51%) and 3) drug interactions may worsen prognosis (49%). 76% (n=68) have never conducted LVAD implantations in HIV+ pts and 20% marked HIV+ as a contraindication. Overall, 34 LVAD implantations in HIV+ pts were reported. 61% replied that a device-related infection in HIV+ is the most significant concern. Conclusions 1) Most centers either explicitly consider or de-facto treat HIV+ status as contraindication for advanced HF therapy. 2) Short life expectancy, transformation to AIDS, drug interaction and higher susceptibility to infection are the major concerns. 3) Clinical outcomes of OHT and LVAD implantation in HIV+ patients are similar to the general population. The cardiology community is still not ready to indiscriminately offer advanced HF therapy to these pts. This negative position may prevent some HIV pts, who are otherwise good candidates, from receiving adequate advanced HF therapy. [ figure 1 ]
An examination of the competition between bulk behavior and interfacial behavior of ceramics subjected to dynamic pressure-shear loading

Abstract A grain level micromechanical analysis of ceramic microstructures subjected to dynamic compression–shear loading conditions is presented. The investigation consists of a combined experimental/numerical approach in which bulk and surface properties are examined by means of pressure–shear impact experiments for a ceramic plate in contact with steel plates. The model for the ceramic microstructure accounts for heterogeneities and randomness in grain orientation and composition. A cohesive zone model is included to capture inter-granular microcrack initiation and evolution as a natural outcome of the calculated material response. Surface roughness is also included in the analysis to capture the time-dependent frictional behavior of the various interfaces. The model for the steel anvil plate accounts for visco-plasticity, thermal softening and strain hardening. Representative volume elements of ceramic microstructure and anvil plates are considered to account for features observed in real experiments. Pressure–shear impact velocity histories are used not only to identify inelasticity, but also to determine dominant failure modes. Bridging between micro- and macroscales is achieved by using the developed model. Simulated velocity histories have been found to be in a good agreement with the experimental observations when bulk and surface features are included in the analysis. However, it is demonstrated that information gathered from these experiments is not sufficient to determine the mechanical behavior of the brittle material. Instead, the velocity histories provide important information on the time-dependent frictional behavior of the specimen–anvil interfaces.
Extracorporeal membrane oxygenation in patients undergoing superior cavopulmonary anastomosis.

Objective Patients who have undergone the superior cavopulmonary anastomosis (Glenn procedure) have unique cardiopulmonary-cerebral physiology that may limit the success of cardiopulmonary resuscitation and extracorporeal membrane oxygenation (ECMO). Limited data published to date suggest grim morbidity and mortality when ECMO is used. We utilized the Extracorporeal Life Support Organization registry database to more thoroughly assess outcomes in these patients. Methods Data from the Extracorporeal Life Support Organization registry from 1999 to 2012 for children with Glenn physiology aged 3 months to 1 year were retrospectively analyzed. Demographics and ECMO characteristics were compared between survivors and nonsurvivors. Factors associated with mortality were evaluated using multivariate logistic regression. Results Of 103 infants, 42 (41%) survived to hospital discharge. Neurologic complications (eg, seizure, hemorrhage, or embolic stroke) were documented in 23% of patients (24 of 103) and 14% of survivors (6 of 42). In univariate analysis, inotropic requirement before ECMO, duration of ECMO, mechanical complications with the ECMO circuit, renal failure, and pulmonary hemorrhage or pneumothorax were predictors of mortality. In multivariate logistic regression, inotrope requirement (odds ratio [OR], 3.6; 95% confidence interval [CI], 1.3-9.8), longer duration of ECMO support (OR, 7.2; 95% CI, 1.8-28), combined cardiopulmonary indication for ECMO (OR, 3.7; 95% CI, 1.4-9.7), and renal failure (OR, 4.2; 95% CI, 1.5-12) were associated with mortality. Conclusions Mortality in infants with Glenn physiology supported with ECMO is lower than that previously reported, but the incidence of neurologic injury is high. These data support use of ECMO in patients with Glenn physiology with refractory cardiopulmonary failure.
Gordon Tullock’s Contribution to spontaneous order studies

The Fund for the Study of Spontaneous Order at the Atlas Economic Research Foundation was established to reward and encourage scholarship pushing the boundaries of economic methodology beyond the realm of the market economy.1 The intellectual impetus for the project comes from a remark that Ludwig von Mises often made in his classes in the 1950s and 1960s. Praxeology, Mises argued, was a general science of human action. Mises insisted that while economics was the best developed branch of praxeology, it did not exhaust the discipline. Outside of the market context, the general science of human action also applied, but too few scholars were working on those topics. The same methodological individualism and invisible-hand reasoning that, according to Mises, were the hallmark of the economic analysis of market phenomena could be deployed to explain politics and law, human sexual relations and family structures, war and revolution, religion and ideology, etc. In order to encourage a new generation of scholars to work along these Misesian lines of inquiry outside the strict confines of the analysis of market processes, the Fund established both research awards for scholars (junior and senior level) and also a Lifetime Achievement Award. The Lifetime Achievement Awards were established to reward trailblazers in the development of the discipline of praxeology beyond economics, and to encourage assessment by the younger generation of the continuing relevance of the contributions to contemporary scholarship. The first recipients of the Lifetime Achievement Award were Eleanor and Vincent Ostrom, and a symposium on their work was published in the Journal of Economic Behavior and Organization 57(2) June 2005. In 2006, Gordon Tullock was selected as the second recipient of this Lifetime Achievement Award. In the spring of 2007, a conference was held at the GMU School of Law to honor Gordon and his contributions to spontaneous order studies. Bill Dennis and Charles
Reactive and proactive control in incarcerated and community adolescents and young adults

Abstract This study compared the cognitive control skills of male incarcerated adolescents ( n = 44), male control adolescents ( n = 33), male incarcerated young adults ( n = 41), and male control young adults ( n = 35) using the AX-continuous performance test (AX-CPT). This test measures proactive control (the ability to maintain a mental representation of goal-related information in preparation for a behavioral response) and reactive control (the ability to activate goal-related information in response to an external trigger). Incarcerated individuals had more difficulty implementing proactive control, whereas control individuals had more difficulty implementing reactive control. Adolescents had more difficulty with both reactive and proactive control compared with young adults, suggesting that both skills improve with age. Additional analyses indicated that the effect of age on proactive control was due to the presence of attention-deficit/hyperactivity disorder, whereas the effect of age on reactive control appeared to be a natural developmental trend that could not be explained by other variables. These findings are considered in relation to the dual mechanisms of control theory [Braver, T. S., Gray, J. R., & Burgess, G. C. (2007). Explaining the many varieties of working memory variation: Dual mechanisms of cognitive control. In A. R. A. Conway, C. Jarrold, M. J. Kane, A. Miyake, & J. N. Towse (Eds.), Variation in Working Memory . New York: Oxford University Press.].
Adherent cells in tumor immunity.

Abstract The present studies explored the role of adherent cells in tumor immunity. Lymph node cells from mice bearing large tumors appeared to be maximally stimulated in vivo and incapable of further stimulation by cells of the same tumor in vitro . Removal of the adherent cell population resulted in a marked decrease in the spontaneous background activity of the remaining nonadherent cells and allowed these cells to undergo stimulation when cultured in the presence of mitomycin-blocked tumor cells. The role of the adherent cell in the maintenance of a state of continuous stimulation was further elucidated by experiments in which lymph node cell populations were reconstituted from the adherent and nonadherent subpopulations. It was also shown that adherent lymphoid cells from tumor-bearing mice, but not from normal mice, were capable of stimulating tumor-immune lymphocytes in a manner similar to intact mitomycin-blocked tumor cells.
The future of refugee flows and policies.

The number of forced migrants...is estimated today to exceed 40 million [worldwide]. The changed international climate of the 1990s...has shifted the focus from the asylum and resettlement countries to the countries of origin: there is today a greater willingness to intervene in other countries affairs either to avert the creation of new flows of focused migrants or to assist internally displaced populations and there is the expectation of large-scale voluntary returns of refugees in asylum. This article discusses these and other policy issues concerning forced migration in this new international environment. (EXCERPT)
Common principles in protein folding and antigen presentation.

Abstract The regular recurrence of hydrophobic amino acid residues along a peptide sequence determines the formation of a longitudinal hydrophobic strip when the peptide forms an α-helix. An understanding of the ways this may effect both folding of nascent proteins and antigen presentation should facilitate vaccine and therapeutics design.