cssi/SciSciGPT-SciSciNet huggingface dataset:
A rapid, semi-automated procedure for the evaluation of leukocyte locomotion in the micropore filter assay.

Abstract A commercially available bacterial colony counter has been modified to allow rapid, accurate, semi-automated evaluation of cell numbers in the micropore filter assay for chemotaxis. The method is valuable for objective, rapid evaluation of cell counts at various levels through the filter, as well as counts on the distal surface of the filter. Coupled with a programmable calculator, this instrument had made feasible a new method of assessing random migration by the regression line analysis, which discriminates between migration rate and mass migration of cells. This combination of equipment may thus serve as a considerable time saving accessory to laboratories engaged in cell locomotion research, but also will allow more rigorous assessment of differences among specific populations of cells.
Fluid Shear Stress Modulates S1P-Induced Endothelial Cell Invasion Into Three-Dimensional Matrices

Endothelial cells are subjected to biochemical and mechanical stimuli which regulate their angiogenic potential. We determined the synergistic effects of sphingosine-1-phosphate (S1P) and fluid shear wall stress (WSS) on the invasion of human umbilical vein endothelial cells (HUVECs) into three-dimensional collagen matrices. A collagen gel was incorporated into a parallel-plate flow chamber to apply controlled WSS to the surface of HUVEC monolayers over a period of 24hr. Cell invasion into the gels required the presence of S1P, with the effects of S1P being enhanced by WSS to an extent comparable to growth factor (VEGF + FGF-2) stimulation. The number of invading cells depended on the magnitude of WSS, with a maximal induction at a WSS of ∼5 dyne/cm2. The enhancement of invasion by WSS coincided with the phosphorylation of Akt and MMP-2 activation. These results provide evidence that WSS is a positive modulator of S1P-induced EC invasion into collagen gels and may contribute to the localization of sprouting angiogenesis at regions of low WSS such as post-capillary venules.Copyright © 2008 by ASME
An Empirical Model of Slope Ratio Comparisons

Comparing slopes is a fundamental graph reading task and the aspect ratio chosen for a plot influences how easy these comparisons are to make. According to Banking to 45°, a classic design guideline first proposed and studied by Cleveland et al., aspect ratios that center slopes around 45° minimize errors in visual judgments of slope ratios. This paper revisits this earlier work. Through exploratory pilot studies that expand Cleveland et al.'s experimental design, we develop an empirical model of slope ratio estimation that fits more extreme slope ratio judgments and two common slope ratio estimation strategies. We then run two experiments to validate our model. In the first, we show that our model fits more generally than the one proposed by Cleveland et al. and we find that, in general, slope ratio errors are not minimized around 45°. In the second experiment, we explore a novel hypothesis raised by our model: that visible baselines can substantially mitigate errors made in slope judgments. We conclude with an application of our model to aspect ratio selection.
On badly approximable functions

Received November 2, 1974 1. INTRODUCTION Let D be a bounded domain in the complex plane with boundary r, and let A(D) be the algebra of analytic functions on D which extend continuously to r. The distance from a function v E C(r) to A(D) is defined to be 4~ A(D)) = W F -fll :f~ A(D)), where the norm is the supremum norm over r. In this paper, we consider the problem of describing the functions 9) E C(I’) which satisfy Such functions, excepting the function 0, will be called
Evidence for the Intracomplex Reaction in Gattermann−Koch Formylation in Superacids: Kinetic and Regioselectivity Studies

Kinetic and regioselectivity data are reported for the Gattermann−Koch formylation of m-xylene, 1-methylnaphthalene, and toluene in HF−SbF5 and CF3SO3H−SbF5 as a function of SbF5/substrate molar ratio. The kinetic study for m-xylene formylation in HF−SbF5 provided crucial evidence in favor of intracomplex reaction via a third-order rate equation, [ArH][ArH2+SbF6-][CO], where the formylation electrophile HCO+ is generated by CO protonation by the arenium ion. Dependence of regioselectivity on substrate, superacid, and SbF5/substrate molar ratio showed that high para regioselectivity stems from intracomplex reaction and the observed regioselectivity reflects the ratio between the intracomplex and the conventional reactions. Comparison in regioselectivity between Gattermann−Koch formylation and Friedel−Crafts formylation with use of HCOF suggested that regioselectivity trends do not reflect the nature of the electrophile but the reaction pathway; the Friedel−Crafts formylation also appears to have intracompl...
Intramolecular hydrophosphination/cyclization of phosphinoalkenes and phosphinoalkynes catalyzed by organolanthanides: scope, selectivity, and mechanism.

Organolanthanide complexes of the general type Cp‘2LnE(TMS)2 (Cp‘ = η5-Me5C5; Ln = La, Sm, Y, Lu; E = CH, N; TMS = SiMe3) serve as effective precatalysts for the rapid intramolecular hydrophosphination/cyclization of the phosphinoalkenes and phosphinoalkynes RHP(CH2)nCHCH2 (R = Ph, H; n = 3, 4) and H2P(CH2)nC⋮C−Ph (n = 3, 4) to afford the corresponding heterocycles and respectively. Kinetic and mechanistic data for these processes exhibit parallels to, as well as distinct differences from, organolanthanide-mediated intramolecular hydroamination/cyclizations. The turnover-limiting step of the present catalytic cycle is insertion of the carbon−carbon unsaturation into the Ln−P bond, followed by rapid protonolysis of the resulting Ln−C linkage. The rate law is first-order in [catalyst] and zero-order in [substrate] over approximately one half-life, with inhibition by heterocyclic product intruding at higher conversions. The catalyst resting state is likely a lanthanocene phosphine−phosphido complex, and dime...
Cytotoxicity mediated by human Fc receptors for IgG

The Fc receptors for IgG(Fc gamma R) play a major role in the removal of antibody-coated infectious agents and may be important molecules for triggering cytotoxicity of tumor cells; they may also serve as an entry for infection of Fc gamma R-bearing cells by viral (including HIV and Dengue), and perhaps other infectious agents. Although central to immune defense, an understanding of the role of these Fc gamma R in cytotoxicity has been complicated in part by the presence of several biochemically distinct types of receptor that have different distributions, specificities, affinities and modes of activation for killing. The development of monoclonal antibodies specific for Fc gamma R on human leukocytes has established the existence of three distinct Fc gamma R and furthermore has helped clarify the function of each of these receptors. In this review, Michael Fanger and colleagues discuss the use of Fc gamma R-specific mAb and the hybridoma cell lines that produce them in examining the ability of each of these unique receptors to mediate killing of tumor and red cell targets. In particular, the use of self-directed hybridoma cells as a model of tumor-cell killing and of bi-specific antibodies to link target cells to effector cells through the different Fc gamma R is discussed. The results of these studies suggest that the ability of a given Fc gamma R to trigger killing is sometimes dependent on the type of Fc gamma R, but is also markedly influenced by the type of target cell and by the nature and state of activation of the effector cell.
Energy-loss radiography with a scanning MeV-ion microprobe

Abstract Beams of 3 MeV H+, He+ and Ne+ ions are focused to dimensions of the order of 5 μm in a scanning ion microprobe and are rastered across a specimen. Residual energies of individual ions transmitted through the specimen are measured with a Si(SB) detector at each point of a 256×256 grid. These data are reconstructed as microradiographs. Examples are shown which illustrate contrast ranges, spatial resolution, sensitivity and noise reduction techniques.
AMINOACIDURIA AS AN INDICATOR OF PHENYLAIANINE AND/OR CALORIC DEFICIENCY IN TREATED PKU PATIENTS

Successful treatment of phenylketonuria (PKU) depends upon neonatal diagnosis and optimum combination of dietary phenylalanine and calories, especially in the first 3 months. Head circumference increases and “catch up” growth occurs with such dietary optimum. This acceleration requires appropriate changes in dietary phenylalanine and calories. Low serum phenylalanine concentrations (<2 mg/100 ml) indicate increased phenylalanine requirement but increased caloric needs are harder to determine. Of 19 infants with PKU, identified by neonatal screening and treated by phenylalanine restriction since January 1967, 15 excreted increased amounts of urinary amino acids, usually glycine, alanine, methionine and phenylalanine, but occasionally others as well. Unappeased appetite, deceleration in head circumference change, and amino-aciduria were usually corrected by increasing dietary phenylalanine. In some cases, when the serum phenylalanine was high, improvement in these criteria was accomplished by increasing dietary calories without increasing phenylalanine intake. Diet prescriptions during the first 3 months required phenylalanine increases to as high as 125 mg/Kg body wt. and calories to as high as 185/kg. Appropriate decreases were possible after 4 to 6 months and allowances per unit body wt. were usually stable after 1 year. Aminoaciduria appeared to reflect an improper dietary balance.
Response of Spartina patens to increasing levels of salinity in rapidly subsiding marshes of the Mississippi River deltaic plain

Abstract Spartina patens (Ait.) Muhl. plants were collected from a Mississippi River deltaic plain brackish marsh located along the Louisiana Gulf Coast. The plants were subjected to salinity levels of 4 to 22 ppt under controlled environment conditions. Salt water instrusion is currently occurring in much of Louisiana's extensive S. patens brackish marshes due to rapid coastal subsidence and that impact is simulated in this study. Specifically, the influence of salt water influx on the stomatal behaviour and net photosynthesis of S. patens was studied. Stomatal conductance was reduced 54% and net photosynthesis 43% as soil salinity was increased from 0 to 22 ppt. Both responses were rapid (within 24 h) and persisted throughout the entire experiment. Salt excretion from both leaf surfaces was noted within three to five days after salt application. Results presented suggest that salt water intrusion is contributing to the rapid rate of marsh deterioration occurring in coastal Louisiana.
Paroxysmal atrial tachycardia with atrioventricular block

Abstract 1. (1) During a four year period in which over 16,000 electrocardiograms were reviewed, 40 episodes of atrial tachycardia with block occurring in 39 patients were encountered. Fifty instances of supraventricular tachycardia with normal A-V conduction occurred during the same period. 2. (2) Sixteen episodes were associated with digitalis intoxication, while 24 were unrelated to digitalis administration. All patients were suffering from advanced organic heart disease. In the absence of digitalis toxicity, the occurrence of atrial tachycardia with block may be considered to be somewhat comparable in significance to the occurrence of other atrial arrhythmias. 3. (3) The atrial rates varied from 135–250 and the atrioventricular block was usually 2:1 or Wenckebach in type. Simultaneous atrial and nodal tachycardia occurred in three patients, all of whom were intoxicated with digitalis. 4. (4) When digitalis intoxication was present, the administration of potassium salts usually terminated the arrhythmia. In one instance, intravenous magnesium sulfate was efficacious. In the absence of excessive digitalis administration, potassium was of no therapeutic value. 5. (5) Eleven patients in this series died. In only one instance was the arrhythmia considered to be an important contributing cause in the death of the patient. Of the eight patients in this series with acute myocardial infarction, six died while in the hospital. The prognosis with the arrhythmia usually depended on the severity of the underlying heart disease.
EXPERIMENTAL PNEUMONIA IN GUINEA PIGS : II. EFFECT OF ANTI-AUTOLYSATE SERA ON PNEUMOCOCCUS PNEUMONIA IN GUINEA PIGS.

1. Anti-pneumotoxic sera prepared in rabbits or horses by immunization with sterile filtrates of the pneumotoxin, under certain conditions protect against the pneumonia caused by the intratracheal injections of mixtures of living pneumococci and toxic autolysates. 2. The protection against the development of pneumonia is heterologous, at least as regards Type I, Type II, viz.: an anti-autolysate serum prepared by the immunization with a pneumotoxin from one type of pneumococcus will prevent the development of pneumonia caused by the injection of pneumococci and autolysate from another type. 3. Certain anti-pneumococcus horse sera used in the treatment of pneumonia in man, either contain no heterologous pneumonia-preventing antibodies or slight amounts only. These sera, however, protect against the pneumonia produced by injections of pneumococci and pneumotoxin of the homologous strain, the degree of protection depending on the amount of specific protective substances such sera contain. 4. Anti-pneumotoxic sera produced in rabbits or horses by the injection of sterile Berkefeld filtrates of the toxic autolysates contain no pneumococcus specific protective substances.
Labor contracts, informational discrepancies and the role of monetary policy☆

Abstract This paper examines output stabilization and inflationary consequences of short-run monetary policy. The macroeconomic framework incorporates informational discrepancies between the monetary authority and economic agents who form long-term labor contracts. Economic agents are assumed to form rational expectations of the rate of inflation. One result of the analysis is that optimal monetary policy rules for stabilizing fluctuations in output and inflation are independent of the structure of the wage contracts and the degree of informational discrepancy. A second proposition shows that the monetary authority can actually make use of specific knowledge concerning the contract structure to reduce fluctuations in the rate of change in output. In particular, the monetary authority can reduce fluctuations in output below those occurring in a frictionless system by increasing fluctuations in the rate of inflation.
New modular high voltage LDMOS technology based on Deep Trench Isolation and 0.18um CMOS platform

This paper presents the challenges of integrating 70V and 45V lateral DMOS transistor modules into a 0.18um base line process. This integration is achieved with minimal impact on baseline process and circuit IP's. Multi-epitaxial stack and Deep Trench Isolation (DTI) modules assure up to 140V isolation capability between different areas in the chip.
Cytoskeletal tension induces the polarized architecture of the nucleus

The nuclear lamina is a thin filamentous meshwork that provides mechanical support to the nucleus and regulates essential cellular processes such as DNA replication, chromatin organization, cell division, and differentiation. Isolated horizontal imaging using fluorescence and electron microscopy has long suggested that the nuclear lamina is composed of structurally different A-type and B-type lamin proteins and nuclear lamin-associated membrane proteins that together form a thin layer that is spatially isotropic with no apparent difference in molecular content or density between the top and bottom of the nucleus. Chromosomes are condensed differently along the radial direction from the periphery of the nucleus to the nuclear center; therefore, chromatin accessibility for gene expression is different along the nuclear radius. However, 3D confocal reconstruction reveals instead that major lamin protein lamin A/C forms an apically polarized Frisbee-like dome structure in the nucleus of adherent cells. Here we show that both A-type lamins and transcriptionally active chromatins are vertically polarized by the tension exercised by the perinuclear actin cap (or actin cap) that is composed of highly contractile actomyosin fibers organized at the apical surface of the nucleus. Mechanical coupling between actin cap and lamina through LINC (linkers of nucleoskeleton and cytoskeleton) protein complexes induces an apical distribution of transcription-active subnucleolar compartments and epigenetic markers of transcription-active genes. This study reveals that intranuclear structures, such as nuclear lamina and chromosomal architecture, are apically polarized through the extranuclear perinuclear actin cap in a wide range of somatic adherent cells.
Killer B lymphocytes: the evidence and the potential

Immune regulation plays a critical role in controlling potentially dangerous inflammation and maintaining health. The Fas ligand/Fas receptor axis has been studied extensively as a mechanism of killing T cells and other cells during infections, autoimmunity, and cancer. FasL expression has been primarily attributed to activated T cells and NK cells. Evidence has emerged that B lymphocytes can express FasL and other death-inducing ligands, and can mediate cell death under many circumstances. Among B cell subsets, the expression of both Fas ligand and IL-10 is highest on the CD5+ B cell population, suggesting that CD5+ B cells may have a specialized regulatory function. The relevance of killer B cells to normal immune regulation, disease pathogenesis, and inflammation is discussed.
Analysis of Haemophilus influenzae type b lipooligosaccharide‐synthesis genes that assemble or expose a 2‐keto‐3‐deoxyoctulosonic acid epitope

Summary We recently isolated a recombinant phage from a Haemophilus influenzae type b (Hib) library that assembles an oligosaccharide with an apparent molecular weight of 1400 (1.4 K) on a 4.1 K Escherichia coli lipopolysaccharide (LPS) structure, producing a 5.5 K LPS species that contains a KDO (2-keto-deoxyoctulosonic acid) epitope. Subcloning and deletional analysis of the 14 kb Haemophilus insert showed that three overlapping restriction fragments contained within a 7.2 kb pstl–Bam HI fragment sequentially modified an E. coli 4.1 K LPS structure, generating novel species of 4.5K, 5.1K and 5.5K. Only the 5.5K species contained the KDO epitope. We confirmed the relationship between the cloned genes and Hib lipooligosaccharide (LOS) biosynthesis by constructing a mutant that expressed an altered LOS. Thus, the Hib 7.2 kb Pstl-Bam Hl restriction fragment contained a cluster of at least three genetic loci whose products acted sequentially in LOS biosynthesis.
The atomic-scale unit, entity: key to a direct and easily understood definition of the SI base unit for amount of substance

The atomic-scale unit, entity (ent), is defined as the number-specific amount of substance, n/N, the amount of substance of a single entity. This unit is an invariant physical quantity (the reciprocal of the Avogadro constant) that serves as the basis for redefining the SI base unit for amount of substance in a direct and easily understood manner. It is argued here that the kilomole should be the base unit in order to avoid factors of 10−3 or 103 appearing in relationships involving both mass and amount of substance expressed in base units. Since, in a compatible formulation, the amount-specific number of entities, N/n (= NA), is equal to Mu/Da, exactly, where Mu = kg kmol−1 = g mol−1 = Da ent−1, exactly, then NA = (kg/Da) kmol−1 = (g/Da) mol−1 = 1 ent−1, exactly. The kilomole can thus be defined very simply as: , exactly, where , the exact kilomole-to-entity amount ratio, is identical to the kilogram-to-dalton mass ratio: . The Avogadro constant, , does not appear explicitly in the defining equation, its reciprocal having been replaced by one entity. Like the dalton, the entity would be categorized as a unit in use with SI.
Deformation and Failure of Collagenous Tissues: A Multi-Scale Study

Fibrous proteins constitute critical building blocks of life, forming biological materials such as hair, bone, skin, spider silk or cells, which play an important role in providing key mechanical functions in biological systems. However, the fundamental atomistic and molecular deformation and fracture mechanisms of biological protein materials remain largely unknown, partly due to a lack of understanding of how individual protein building blocks respond to mechanical load.Copyright © 2009 by ASME
Studies on the Relative Bacterial Cleanability of Milk-Contact Surfaces

Summary These studies are concerned with the removal of bacteria, deposited with various soils, on milk-contact surfaces. The bacteria were labeled with Phosphorus 32 , incorporated into test soils, dried down with the soils upon various milk-contact surfaces under highly reproducible conditions, removed by a standard cleaning procedure, and assayed by the agar-submersion, Geiger-counting, and autoradiographic techniques. The data so derived were tested for significance by an Analysis of Variance, and grouped by the Duncan Multiple Range Test. The results show statistically significant differences in cleanability, between different surface finishes applied to a given material and between different materials having comparable finishes. Organisms suspended in a homogenized whole milk soil were much more easily removed from the surfaces studied than organisms suspended in an 0.85% saline solution. Multiple soiling and washing of a surface results in a general increase in the number of bacteria retained by a surface. Brushing was found to be effective in cleaning smooth polished, ground, and molded surfaces, and relatively ineffective in removing bacteria entrapped in the surface features of cold rolled, abraded, blasted, and porous surfaces. On the basis of all the tests performed, the surface finishes which displayed the greatest ease of cleanability were the highly polished, nonporous surfaces. The finely ground and smoothly molded finishes followed close behind, and the cold rolled, abraded, blasted, and porous finishes were the most difficult to clean. Under the conditions of testing utilized in these experiments, the direct agar-submersion technique proved to be ineffective as a means of accurately determining the relative cleanability of different surface finishes and of different materials. The radiological counting procedure proved to have higher reproducibility than agar-submersion methods for estimating the numbers of bacteria remaining on a cleaned surface.
The molecular mobility of α-actinin and actin in a reconstituted model of gelation

Dictyostelium discoideum alpha-actinin (D.d. alpha-actinin) is a calcium and pH-regulated actin-binding protein that can cross-link F-actin into a gel at a submicromolar free calcium concentration and a pH less than 7 [Fechheimer, et al., 1982]. We examined mixtures of actin and D.d. alpha-actinin at four pH and calcium concentrations that exhibited various degrees of gelation or solation. The macroscopic viscosities of these mixtures were measured by falling ball viscometry (FBV) and compared to the translational diffusion coefficients measured by gaussian spot and periodic-pattern fluorescence photobleaching recovery (FPR) of both the actin filaments and D.d. alpha-actinin. A homogeneous, macroscopic gel was not composed of a static actin network. Instead, the filament diffusion coefficient decreased to approximately 65% of the control value. If the D.d. alpha-actinin concentration was increased, the solution became inhomogeneous, consisting of domains of higher actin concentration. These domains were often composed of a static actin network. The mobility of D.d. alpha-actinin consisted of a major fraction that freely diffused and a minor fraction that appeared immobile under the conditions employed. This suggested that D.d. alpha-actinin binding to the actin filaments was static over the time course of measurement (approximately 5 sec). Under solation conditions, there was no apparent interaction of actin with D.d. alpha-actinin. These results demonstrate that 1) actin filaments need not be cross-linked into an immobile, static array in order to have macroscopic properties of a gel; 2) interpretation of the rheological properties of actin:alpha-actinin gels are complicated by spatial heterogeneity of the filament concentration and mobility; and 3) a fraction of D.d. alpha-actinin binds statically to actin in undisturbed gels. The implications of these results are discussed in relation to cytoplasmic structure and contractility.
Solanezumab for Alzheimer's disease

Introduction: Alzheimer's disease (AD) is a debilitating neurodegenerative illness affecting over 35 million people worldwide. Solanezumab is a monoclonal antibody that binds to β-amyloid (Aβ), a p...
Chloride Channels in Basolateral TAL Membranes. XVIII. Phenylglyoxal Induces Functional mcClC-Ka Activity in Basolateral MTAL Membranes

Cultured mouse MTAL cells contain more mRNA encoding the Cl− channel mcClC-Ka, which mediates CTAL Cl− absorption, than mRNA encoding the Cl− channel mmClC-Ka, which mediates MTAL Cl− absorption. mmClC-Ka and mcClC-Ka have three functional differences: 1) mmClC-Ka open time probability, P o, increases with increasing cytosolic Cl−, but variations in cytosolic Cl− do not affect P o in mcClC-Ka; 2) mmClC-Ka is gated by (ATP + PKA), while (ATP + PKA) have no effect on P o in mcClC-Ka; and 3) mmClC-Ka channels have single-ion occupancy, while mcClC-Ka channels have multi-ion occupancy. Using basolateral vesicles from MTAL cells fused into bilayers, we evaluated the effects of 1 mM cytosolic phenylglyoxal (PGO), which binds covalently to lysine or arginine, on Cl− channels. With PGO pretreatment, Cl− channels were uniformly not gated either with increases in cytosolic-face Cl− or with (ATP + PKA) at 2 mm cytosolic-face Cl−; and they exhibited multi-ion occupancy kinetics typical for mcClC-Ka channels. Thus, in basolateral MTAL membranes, blockade of Cl− access to arginine or lysine residues on mmClC-Ka by PGO results in Cl− channels having the functional characteristics of mcClC-Ka channels.
Graduate Education and the Evolving genre of Electronic Theses and Dissertations

Abstract Electronic writing spaces are transforming graduate education—enhancing mentoring and the shape of dissertation content. In this article, we review international efforts to develop the Networked Digital Library of Theses and Dissertations (NDLTD). We examine the need to amplify access to current scholarship, the need for training materials and centralized metadata, and the need to develop multi-language search interfaces. We explore ways traditional print dissertations are being remediated by electronic writing. We analyze challenges to implementing ETD initiatives, including concerns about preservation, attitudes toward intellectual property, and the training challenges involved in deploying technology to present new research using media and interactive perspectives. We conclude that universities need to develop and support ETD initiatives to provide broader access to their research and to provide students with the training and tools they need to present their knowledge more effectively in a digital world.
Genome-Wide Analysis of CREB Target Genes Reveals A Core Promoter Requirement for cAMP Responsiveness

We have employed a hidden Markov model (HMM) based on known cAMP responsive elements to search for putative CREB target genes. The best scoring sites were positionally conserved between mouse and human orthologs, suggesting that this parameter can be used to enrich for true CREB targets. Target validation experiments revealed a core promoter requirement for transcriptional induction via CREB; TATA-less promoters were unresponsive to cAMP compared to TATA-containing genes, despite comparable binding of CREB to both sets of genes in vivo. Indeed, insertion of a TATA box motif rescued cAMP responsiveness on a TATA-less promoter. These results illustrate a mechanism by which subsets of target genes for a transcription factor are differentially regulated depending on core promoter configuration.
Bismuth silicon oxide as a holographic storage medium

Photorefractive crystals are being used as a means of capturing the spatial information of two coherent light sources interacting within them. Typical recording procedures, important crystal parameters, as well as holographic applications are described.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Selective Inhibition of Engineered Receptors via Proximity-Accelerated Alkylation

A new approach for creating allele-specific inhibitors is demonstrated. In this approach, a receptor and ligand are engineered to contain complementary reactive groups that form a covalent bond via a proximity-accelerated reaction upon formation of the receptor-ligand complex, irreversibly modulating the biological function of the receptor. This approach is demonstrated in the cyclophilin-cyclosporin receptor-ligand system by introducing thiol and acrylamide functional groups in the receptor and ligand, respectively.
Switch and maintenance of task set in schizophrenia

Task set maintenance and switching deficits are robust in schizophrenia. However, little is known about how these constructs are related to one another. The development of an improved understanding of set switching and maintenance deficits in schizophrenia requires that these constructs be explicated in terms of elementary cognitive processes rather than grouped into broad psychological concepts like executive functioning. A relevant dichotomy has been proposed in which sensory and perceptual ("attentional") processes are distinguished from decisional ("intentional") processes in task maintenance and switching; however, the contributions these processes make to performance deficits in schizophrenia is not known. In the present study, 30 participants with schizophrenia and 27 healthy comparisons completed a cued attentional set switching task. In addition to analyses of mean response times, the contributions of attentional and intentional processes to task performance were estimated using an ex-Gaussian distributional analysis. Schizophrenia was associated with a set maintenance deficit that was accounted for by an attentional, rather than intentional, dysfunction. Both groups showed significant switch costs that could be attributed to attentional processes, but there was no evidence for an attentional set switching deficit in schizophrenia. The findings suggest that set switching and set maintenance may reflect distinct cognitive deficits in schizophrenia and that they may be associated with unique information processing mechanisms.
Anxieties of Legitimacy: The Origins and Influence of the “Classicist Stance” in American Rhetoric Studies

This article describes an origin of the “classicist stance,” Nan Johnson's term for the emphasis on the classical past in American rhetoric historiography. It argues that adherence to the classical past arises from an anxiety about conducting research evident in the field in the early twentieth century, an anxiety that develops into fears about institutional legitimacy later in the century. The article closes by urging scholars of rhetoric in the modern era to embrace print modernity as their researh framework, rather than classicism.
Flux flow noise power spectra in the presence of local pinning interactions

We derive expressions for the dc flux flow voltage and for the flux flow noise power spectrum in type II superconductors using a model in which flux bundles travel a distance1 less than the sample widthL before being stopped for finite times by local pinning interactions. The frequency dependence of the power spectrum is shown to be identical to our earlier derivation, where we assumed that pinning and release of flux bundles occurred in zero times, an assumption we now show to be incorrect. This frequency dependence has been shown to lead to good agreement for experimentally measured transit times, which have repeatedly been shown to be too short when obtained from models of uninter-rupted flux transit across the sample width. The concept of a pinned fraction arises naturally in our model, and occurs because of two factors; first, in certain regions the Lorentz force is not sufficient to overcome pinning, and second, in regions where flux flow occurs, fluxoids will be held up for brief periods because of interaction with local pinning centers. The expressions for the noise power at zero frequency and the dc voltage are modified by factors that depend on averages of1.
First-order Wiener kernel visually evoked potentials obtained from multiple sclerosis patients

Visually evoked potentials (VEP) were measured in multiple sclerosis patients with five sizes of reversing check stimuli. The VEPs were obtained using random binary sequence triggered check reversals. The random binary sequence was cross-correlated with scalp potential responses to obtain the estimates of the linear response of the system. For each evaluation a series of five VEPs, one for each of five check sizes, was done. A correlation coefficient was calculated to evaluate check size versus amplitude of the major negative wave. A tabulation was made to compare Snellen chart visual acuity with these correlation coefficients. For the eyes with a Snellen acuity of 20/20, 63% of the VEP amplitudes increased as the check size was decreased with correlation coefficients of -0.6 to -1. For the eyes with a Snellen acuity of 20/70 or less the amplitude decreased with the check size decrease, showing a correlation coefficient of +0.6 to +1 in 45% of the evaluations. The check size giving the largest amplitude was also tabulated with respect to the visual acuity, but did not appear to have as strong a relationship to visual acuity.
Endovascular Thermal Coagulation Using the Double-Helix GDC. Feasibility Study in Experimental Aneurysms.

SUMMARY An experimental study was undertaken to explore the possibility of treating this subset of aneurysms with thermal coagulation. Endovascular endosaccular thermal coagulation of experimental aneurysms was successfully performed using a radiofrequency electrical current applied to a novel device, the double-helix GDC. Theoretically this technique could be utilized in selected patients to occlude large and giant intracranial aneurysms.
Regulation of histone synthesis during early Urechis caupo (Echiura) development

The histones present in mature oocytes and embryos of Urechis caupo and their pattern of synthesis during early development have been characterized. Acid-soluble proteins extracted from mature oocyte germinal vesicles and from embryonic nuclei were analyzed by two-dimensional polyacrylamide gel electrophoresis. Histones are accumulated in the mature oocytes in amounts sufficient to provide for the assembly of chromatin through the 32- to 64-cell stage of embryogenesis. Two H1 histones, which appear to be variants, were found. Germinal vesicles and cleavage-stage nuclei are enriched in H1M (maternal). During late cleavage a faster-migrating H1, H1E (embryonic), appears among the nuclear histones and, as embryogenesis continues, replaces H1M as the predominant H1. No new core histone variants are detected during early development. Examination of [3H]lysine-labeled histones from germinal vesicles and embryonic nuclei reveals stage-specific patterns of histone synthesis. H1M is the major H1 species synthesized in mature oocytes. After fertilization, a switch to the predominant synthesis of H1E occurs. Comparison of the [3H]lysine incorporated into H1E and core histones indicates that H1E synthesis is disproportionately high from midcleavage through the midblastula stage. By the gastrula stage, a balanced synthesis of H1E and each core histone is established. The results indicate that there is noncoordinate regulation of H1 and core histone synthesis during Urechis development.
Tensile bond strength of polyvinyl siloxane impressions bonded to a custom tray as a function of drying time: Part I

Time-dependent bond strength studies of two polyvinyl siloxane impression materials to acrylic resin disks with their respective adhesives were studied to determine the optimal time for maximum bond strength. Six groups were tested with varying adhesive dry times of 0, 7, 15, and 60 minutes and 8 and 24 hours before testing. The results indicated that the bond strength of the adhesive increased at least twofold from time zero to 7 minutes adhesive dry time and peaked at 60 minutes for one of the materials and at 8 hours for the other. Bond strengths increased rapidly to the 15-minute test interval and then seemed to plateau. Both materials exhibited decreased adhesive bond strengths at 24 hours.
A computationally efficient multivariate maximum-entropy density estimation (MEDE) technique

Density estimation is the process of taking a set of multivariate data and finding an estimate for the probability density function (pdf) that produced it. One approach for obtaining an accurate estimate of the true density f(x) is to use the polynomial-moment method with Boltzmann-Shannon entropy. Although rigorous mathematically, the method is difficult to implement in practice because the solution involves a large set of simultaneous nonlinear integral equations, one for each moment or joint moment constraint. Solutions available in the literature are generally not easily applicable to multivariate data, nor computationally efficient. In this paper, we take the functional form that was developed in this problem and apply pointwise estimates of the pdf as constraints. These pointwise estimates are transformed into basis coefficients for a set of Legendre polynomials. The procedure is mathematically similar to the multidimensional Fourier transform, although with different basis functions. We apply this technique, called the maximum-entropy density estimation (MEDE) technique, to a series of multivariate datasets.
Experimental studies of local and global emission uniformity for a magnetron injection gun

We report measurements of the azimuthal emission nonuniformity of a gyrotron's thermionic cathode as determined from two experiments; one which determines the total emission, and one which scans the emitted beam using a rotating probe. In the total emission experiment, which measured the total collector current over a range of voltages, the cathode's total work function spread was found to be 0.033 eV at T=1000/spl deg/C, centered around 1.88 eV. In the subsequent experiment, which used a mechanically rotatable current probe, global, and local effects were investigated. Voltage was varied to examine emission nonuniformities in different regions of cathode operation. While emission became almost completely uniform in the low-voltage space-charge limited regime, emission varied as much as 50% at high voltages. In another part of the current probe experiment, current--voltage curves were measured at azimuthal locations in 30/spl deg/ increments for several cathode temperatures. From this extensive set of data the work function distribution parameters were identified over small sections of the cathode for the entire cathode surface.
Unequal Death in T Helper Cell (Th)1 and Th2 Effectors: Th1, but not Th2, Effectors Undergo Rapid Fas/FasL-mediated Apoptosis

T helper cell (Th) 1, but not Th2, effectors undergo rapid Fas/Fas ligand (FasL)-mediated, activation-induced cell death upon restimulation with antigen. Unequal apoptosis is also observed without restimulation, after a longer lag period. Both effectors undergo delayed apoptosis induced by a non–Fas-mediated pathway. When Th1 and Th2 effectors are co-cultured, Th2 effectors survive preferentially, suggesting the responsible factor(s) is intrinsic to each population. Both Th1 and Th2 effectors express Fas and FasL, but only Th2 effectors express high levels of FAP-1, a Fas-associated phosphatase that may act to inhibit Fas signaling. The rapid death of Th1 effectors leading to selective Th2 survival provides a novel mechanism for differential regulation of the two subsets.
The Peking Express Problem and its Applications

We analyze an interesting queuing system arising from the operation of a fast Chinese food restaurant. Such system allows customers to jump a queue to be served in batches. We use NS-2 simulation to evaluate its performance in terms of throughput, delay and loss rate. We also discuss its application in real network environment
The DSI and below: The architelcture/hardware component of a computer science curriculum

The authors examine the area of computer architecture and identify five courses that as a unit comprise a comprehensive treatment of undergraduate material in that area. The set of courses begins at the sophomore level with a machine-structures course and finishes at the senior level with a comparative architecture course. The authors discuss the focus of this set of courses and the rationale for each. >
Computerization of the Workplace

Divergent conceptualizations of the recent changes in work organization that have accompanied computerization include neo-Bravermanian analyses, postindustrial analyses, and contingency analyses. To make sense of these differing views, the paper surveys sociological research on computerization and its impact on three analytically separate dimensions of the workplace: organizational restructuring, changes in worker skill, and power and authority relationships. The review reveals that computerized work organizations typically have fewer hierarchical levels, a bifurcated workforce, frequently with race and sex segregation, a less formal structure, and diminished use of internal labor markets and reliance instead on external credentialing. Variable patterns of centralization and decentralization occur, and workplace power relationships interact with technological change to produce variable political outcomes. With regard to worker skills, recent evidence suggests aggregate upskilling with some deskilling and ...
Realistic quark and lepton masses through SO(10) symmetry

In a recent paper a model of quark and lepton masses was proposed. Without any family symmetries almost all the qualitative and quantitative features of the quark and lepton masses and Kobayashi-Maskawa mixing angles are explained, primarily as consequences of various aspects of SO(10) symmetry. Here the model is discussed in much greater detail. The threefold mass hierarchy as well as the relations m{sub {tau}}{sup 0}{approx_equal}m{sub b}{sup 0}, m{sub {mu}}{sup 0}{approx_equal}3m{sub s}{sup 0}, m{sub e}{sup 0}{approx_equal}(1)/(3)m{sub d}{sup 0}, m{sub u}{sup 0}/m{sub t}{sup 0}{lt}m{sub d}{sup 0}/m{sub b}{sup 0}, tan{theta}{sub C}{approx_equal}{radical}(m{sub d}{sup 0}/m{sub s}{sup 0}), V{sub cb}{lt}{radical}(m{sub s}{sup 0}/m{sub b}{sup 0}), and V{sub ub}{approximately}V{sub us}V{sub cb} follow from a simple Yukawa structure at the unification scale. The model also gives definite predictions for tan{beta}, the neutrino mixing angles, and proton decay branching ratios. The ({nu}{sub {mu}}{minus}{nu}{sub {tau}}) mixing angle is typically large, tan{beta} is close to either m{sub t}{sup 0}/m{sub b}{sup 0} or m{sub c}{sup 0}/m{sub s}{sup 0}, and proton decay is in the observable range, but there is a group-theoretical suppression factor in the rate. {copyright} {ital 1997} {ital The American Physical Society}
Noninvasive estimation of cardiac output

A noninvasive method of measuring cardiac output is described. The method uses adaptive aorta models in conjunction with femoral and carotid pulse contour waveform measurements to calculate aortic flow. Results are presented from measurements on dogs using internal pressure recordings made with fluid-filled catheters and compared with electromagnetic flow measurements taken in the ascending aorta. Preliminary results using external pulse measurements on patients are also presented and compared with thermal dilution measurements. >
Rapid Intermittent Movement of Axonal Neurofilaments Observed by Fluorescence Photobleaching

Observations on naturally occurring gaps in the axonal neurofilament array of cultured neurons have demonstrated that neurofilament polymers move along axons in a rapid, intermittent, and highly asynchronous manner. In contrast, studies on axonal neurofilaments using laser photobleaching have not detected movement. Here, we describe a modified photobleaching strategy that does permit the direct observation of neurofilament movement. Axons of cultured neurons expressing GFP-tagged neurofilament protein were bleached by excitation with the mercury arc lamp of a conventional epifluorescence microscope for 12–60 s. The length of the bleached region ranged from 10 to 60 μm. By bleaching thin axons, which have relatively few neurofilaments, we were able to reduce the fluorescent intensity enough to allow the detection of neurofilaments that moved in from the surrounding unbleached regions. Time-lapse imaging at short intervals revealed rapid, intermittent, and highly asynchronous movement of fluorescent filaments through the bleached regions at peak rates of up to 2.8 μm/s. The kinetics of movement were very similar to our previous observations on neurofilaments moving through naturally occurring gaps, which indicates that the movement was not impaired by the photobleaching process. These results demonstrate that fluorescence photobleaching can be used to study the slow axonal transport of cytoskeletal polymers, but only if the experimental strategy is designed to ensure that rapid asynchronous movements can be detected. This may explain the failure of previous photobleaching studies to reveal the movement of neurofilament proteins and other cytoskeletal proteins in axons.
Preoperative frailty Risk Analysis Index to stratify patients undergoing carotid endarterectomy

Objective Rapid and objective preoperative assessment of patients undergoing carotid endarterectomy (CEA) remains problematic. Preoperative variables correlate with increased morbidity and mortality, yet no easily implemented tool exists to stratify patients. We determined the relationship between our fully implemented frailty-based bedside Risk Analysis Index (RAI) and complications after CEA. Methods Patients undergoing CEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database from 2005 to 2011 were included. Variables of frailty RAI were matched to preoperative NSQIP variables, and outcomes including stroke, mortality, myocardial infarction (MI), and length of stay were analyzed. We further analyzed patients who were symptomatic and asymptomatic before CEA. Results With use of the NSQIP database, 44,832 patients undergoing CEA were analyzed (17,696 [39.5%] symptomatic; 27,136 [60.5%] asymptomatic). Increasing frailty RAI score correlated with increasing stroke, death, and MI (P 10], 5.0%). Among patients undergoing CEA, 88% scored low ( 21, 8.6%. In asymptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 1.6%, whereas if the RAI score is 11 to 15, it is 2.9%; 16 to 20, 5.2%; and >21, 6.2%. Conclusions Frailty is a predictor of increased stroke, mortality, MI, and length of stay after CEA. An easily implemented RAI holds the potential to identify a limited subset of patients who are at higher risk for postoperative complications and may not benefit from CEA.