cssi/SciSciGPT-SciSciNet huggingface dataset:
Quantification of activation patterns during ventricular fibrillation in open-chest porcine left ventricle and septum

Background A single stationary mother rotor has been hypothesized to be responsible for maintenance of ventricular fibrillation (VF) in the guinea pig. Previous studies have pointed to the ventricular septum as a possible location for a mother rotor in the pig heart. Objectives The purpose of this study was to test the hypothesis that a mother rotor is located in the septum. Methods In seven open-chest pigs, we mapped the first 20 seconds of electrically induced VF simultaneously from the posterior left ventricle (LV) and right side of the septum with two electrical arrays. Each array contained 504 electrodes (21 × 24) spaced 2 mm apart in the LV and 1.5 mm apart in the septum. Results The percentage of VF wavefronts that formed reentrant circuits was significantly lower in the septum (1% ± 1% [mean ± SD]) than in the LV (2% ± 1%). The peak frequency during VF also was significantly smaller in the septum (8.6 Hz ± 3.0 Hz) than in the LV (10.4 Hz ± 3.4 Hz). The mean direction of spread of activation of VF wavefronts was away from the region where the posterior LV free wall intersects the posterior septum in both the LV and septum. Conclusions The lower incidence of reentry and lower peak frequency in the mapped region of the septum than in the LV indicate that a mother rotor is not present in swine on the RV side of the septum. The mean directions of the VF activation sequences in the LV and septum suggest that if a mother rotor is present during the first 20 seconds of VF, it exists where the posterior LV free wall joins the septum, the region where the posterior papillary muscle inserts.
Further Development and Validation of the Teaching Science as Inquiry (TSI) Instrument

The purpose of this study was to further develop and validate the Teaching Science as Inquiry (TSI) Instrument, an instrument designed to measure the self-efficacy beliefs of preservice teachers in regards to the teaching of science as inquiry. Based on the validation processes and the associated data analysis, the TSI demonstrates continued content and construct validity with high internal reliability when used with prospective elementary science teachers.
Equivalence of local treewidth and linear local treewidth and its algorithmic applications

We solve an open problem posed by Eppstein in 1995 [14, 15] and re-enforced by Grohe [16, 17] concerning locally bounded treewidth in minor-closed families of graphs. A graph has bounded local treewidth if the subgraph induced by vertices within distance r of any vertex has treewidth bounded by a function of r (not n). Eppstein characterized minor-closed families of graphs with bounded local treewidth as precisely minor-closed families that minor-exclude an apex graph, where an apex graph has one vertex whose removal leaves a planar graph. In particular, Eppstein showed that all apex-minor-free graphs have bounded local treewidth, but his bound is doubly exponential in r, leaving open whether a tighter bound could be obtained. We improve this doubly exponential bound to a linear bound, which is optimal. In particular, any minor-closed graph family with bounded local treewidth has linear local treewidth. Our bound generalizes previously known linear bounds for special classes of graphs proved by several authors. As a consequence of our result, we obtain substantially faster polynomial-time approximation schemes for a broad class of problems in apex-minor-free graphs, improving the running time from 222O(1/e)nO(1) to 2O(1/e)nO(1).
Point defect characterization of GaN and ZnO

Abstract Point defects are created in bulk ZnO and epitaxial GaN by 1–2 MeV electron irradiation at 300 K, and are studied by temperature-dependent Hall effect, photoluminescence, and deep level transient spectroscopy measurements. The N vacancy is identified as a fairly shallow donor in GaN, whereas defect identifications in ZnO are uncertain at this time. Both materials, but especially ZnO, are quite resistant to displacement damage.
Modulation of VE-cadherin and PECAM-1 mediated cell-cell adhesions by mitogen-activated protein kinases.

Endothelial cell transition from a differentiated, quiescent phenotype to a migratory, proliferative phenotype is essential during angiogenesis. This transition is dependent on alterations in the balanced production of stimulatory and inhibitory factors, which normally keep angiogenesis in check. Activation of MAPK/ERKs is essential for endothelial cell migration and proliferation. However, its role in regulation of endothelial cell adhesive mechanisms requires further delineation. Here, we show that sustained activation of MAPK/ERKs results in disruption of cadherin-mediated cell-cell adhesion, down-regulation of PECAM-1 expression, and enhanced cell migration in microvascular endothelial cells. Expression of a constitutively active MEK-1 in mouse brain endothelial (bEND) cells resulted in down-regulation of VE-cadherin and catenins expression concomitant with down-regulation of PECAM-1 expression. In contrast, inhibition of MEK-1 restored parental morphology, cadherin/catenins expression and localization. These data are further supported by our observation that sustained activation of MAPK/ERKs in phorbol myristate acetate incubated HUVEC lead to disruption of cadherin-mediate cell-cell interactions and enhanced capillary formation on Matrigel. Thus, sustained activation of MAPK/ERKs plays an important role in disruption of cell-cell adhesion and migration of endothelial cells.
Effect of gender and fatty acids on ischemic recovery of contractile and pump function in the rat heart.

Abstract Background: Clinical studies have shown that the incidence of heart disease is lower in premenopausal women compared with men. However, women are at increased risk of developing cardiac dysfunction after myocardial infarction. During a myocardial infarction, plasma levels of free fatty acids increase and contribute to postischemic left ventricular dysfunction. Objective: The purpose of this study was to examine the effect of increasing concentrations of fatty acids on recovery of contractile parameters and pump function after 20 minutes of global ischemia and 30 minutes of reperfusion in male and female rat hearts. Methods: Hearts were isolated and perfused with 5.5 mM glucose and 50 μU/mL insulin alone or in the presence of 0.4 or 1.2 mM palmitate. To determine whether inhibition of fatty acid metabolism was accompanied by an improvement in recovery of cardiac function after ischemia, the inhibitor of mitochondrial palmitate uptake, oxfenicine (2 mM), was used in female hearts perfused with 1.2 mM palmitate. Results: Twenty-two female and 21 age-matched male rats were used. In hearts perfused under normoxic conditions, 1.2 mM palmitate reduced cardiac output and systolic pressure in female rat hearts. Heart rate, ventricular contraction, and ventricular relaxation were similar between male and female hearts and were not altered by fatty acids. After transient ischemia, all contractile parameters in male hearts returned to preischemic levels, regardless of the level of fatty acids in the perfusate. Recovery of female hearts, however, was inhibited by fatty acids. Aortic flow, ventricular contraction, ventricular relaxation, and systolic pressure were significantly lower in female hearts compared with male hearts in the presence of 1.2 mM palmitate (P Conclusions: Our data indicate that the female myocardium is more sensitive to the effects of fatty acids after global ischemia compared with male hearts. This confirms that a gender effect exists in the recovery of heart function after ischemia, which can be accounted for by differences in ventricular contraction and relaxation.
Diurnal and annual variation of adrenocortical activity in the squirrel monkey.

Diurnal changes in basal cortisol levels and stress reactivity were assessed in male and female squirrel monkeys. Blood samples were collected at four-hour intervals throughout the day and night in the mating and nonmating seasons. Basal cortisol levels in females were similar in both seasons, but males tended to have higher cortisol levels during the mating season, especially at night. For both sexes, cortisol secretion was highest between 0400 and 0800 preceding the onset of the diurnal activity period. Assessment of cortisol responses following brief handling and anesthesia indicated that stress responses were relatively stable across the year, but cortisol increments were slightly higher in the nonmating season. Cortisol levels post-stress were generally related to prior baseline values. Thus, a knowledge of biorhythmic changes in basal hormone levels was important for predicting hormone levels after acute stressors. Males also underwent marked seasonal variation in their basal testosterone levels, which markedly altered the nature of their testosterone responses 30-minutes poststress. © 1995 Wiley-Liss, Inc.
Research note: microcode bit optimization is NP-hard

The general problem of formating microinstruction so as to minimize the width of words in control memory is shown to be computationally difficult. Hence, we should not attempt to solve the general case, but concentrate on heuristics for reasonable subcases.
Hyperspectral imaging using AOTF and NIR sensing of buried objects and landmines

The detection of landmines and buried objects requires methods that can cover large areas rapidly while providing the required sensitivity to detect the optical and spectroscopic contrasts in soil properties that can reveal their presence. These conditions on contrast and coverage can be met by capturing images of the soil at wavelengths which are sensitive to the properties modified by the presence of buried objects. In this work we investigate both imaging and scanning methods which may have some utility for the detection problem. In the imaging approach, we capture hyperspectral reflection images using an acousto-optic tunable filter (AOTF) and fluorescence images using a long-pass filter. For the scanning method, we acquire data point-by-point over a two-dimensional grid with a single emitter/detector pair. The results illustrate the potential of these two approaches for detection of landmines and buried objects.
O-vacancies in transition metal (TM) oxides: Coordination and local site symmetry of transition and negative ion states in TM2O3 and TMO2 oxides

Removal of neutral O-atoms from a transition metal (TM) oxide results in two electrons residing within the vacated site. Two-electron multiplet theory has been used to develop a d^2equivalent model. When applied to tetragonal HfO"2, the two electrons of neutral vacancy in the d^2 equivalent limit reside on two Hf d-state orbitals in a high-spin configuration. Transition energies and negative ion state features are detected in transition metal (TM) oxides by X-ray absorption spectroscopy (XAS) in the O K pre-edge/sub-band gap energy regime, and are compared with the model. These transitions are from the O 1s^2 doubly occupied core level approximately 543eV below vacuum, and terminate in empty virtual bound states. In addition these strong spin-allowed transitions, spectra include weaker features corresponding to either spin-forbidden transitions in the d^2 model, or alternatively to a near-degeneracy with a singlet ground state with weak Hf-atom pair bonds. The analysis of O K edge XAS spectra identify a significant distinction between multiplet (i) triplet transition energies for neutral O-vacancies that are not active as electron or hole traps, (ii) O-vacancy negative ion states that are active as electron traps in Poole-Frenkel conduction or trap-assisted tunneling (TAT), and (iii) O-vacancy occupied ground states that can trap holes.
Commentary: Making Use of the (Alternative) Media

The following comments are in response to the commentary which appeared in the Fall 1992 issue under the title "Making Use of the Media" (PA 14[4]:2,33-37).—P.J.H.
Isn't it ironic: Using irony to explore the contradictions of organizational life

This study brings together two promising strands of research in organizational communication‐postmodern theories and contradiction‐centered analyses of organizational discourse and practice by employing irony, as articulated by postmodern and/or feminist scholars, as a theoretical lens to analyze the contradictions that structure a social service organization. While many scholars have pointed to ironic organizational outcomes (e.g., agencies that foster client dependence while claiming to encourage independence), few have teased out the discursive complexities that create those ironic conditions (Fraser, 1989; Trethewey, 1997). This case study shifts our focus away from manifestations of contradictions toward the theoretical tools, namely irony, with which we can better understand how ambiguities and paradoxes structure organizational reality.
Religion and place attachment: A study of sacred places

In this paper we claim that religion can play an important role in place attachment and present a conceptualization of it. We provide an understanding of the role of place in the experience of religious place attachment, describing in detail place, design, aesthetics, and special characteristics that facilitate devotion. Next, we describe how attachment to place is learned through the process of socialization involving rituals, use of artifacts, story telling, and place visits. We argue that there is an active socializing component to religious place attachment in addition to the experiential one. We conclude with a brief discussion integrating the complex issues of religion, place, identity, and attachment.
Conservation Ecology: Area Trumps Mobility in Fragment Bird Extinctions

Tropical forest understory birds are highly sensitive to habitat fragmentation. Recent results from a monumental Amazonian fragmentation experiment show that habitat needs of these specialized birds make mobility a liability, leading to their extinctions from forest fragments.
Pharmacological actions of melatonin in oxygen radical pathophysiology

Melatonin, the chief secretory product of the pineal gland, was recently found to be a free radical scavenger and antioxidant. This review briefly summarizes the published reports supporting this conclusion. Melatonin is believed to work via electron donation to directly detoxify free radicals such as the highly toxic hydroxyl radical. Additionally, in both in vitro and in vivo experiments, melatonin has been found to protect cells, tissues and organs against oxidative damage induced by a variety of free radical generating agents and processes, e.g., the carcinogen safrole, lipopolysaccharide, kainic acid, Fenton reagents, potassium cyanide, L-cysteine, excessive exercise, glutathione depletion, carbon tetrachloride, ischemia-reperfusion, MPTP, amyloid beta (25-35 amino acid residue) protein, and ionizing radiation. Melatonin as an antioxidant is effective in protecting nuclear DNA, membrane lipids and possibly cytosolic proteins from oxidative damage. Also, melatonin has been reported to alter the activities of enzymes which improve the total antioxidative defense capacity of the organism, i.e., superoxide dimutase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase, and nitric oxide synthase. Most studies have used pharmacological concentrations or doses of melatonin to protect against free radical damage; in a few studies physiological levels of the indole have been shown to be beneficial against oxidative stress. Melatonin's function as a free radical scavenger and antioxidant is likely assisted by the ease with which it crosses morphophysiological barriers, e.g., the blood-brain barrier, and enters cells and subcellular compartments. Whether the quantity of melatonin produced in vertebrate species is sufficient to significantly influence the total antioxidative defense capacity of the organism remains unknown, but its pharmacological benefits seem assured considering the low toxicity of the molecule.
Rarefied gas models with velocity dependent collision frequencies

Abstract Linearized model Boltzmann equations with realistic velocity dependent collision frequencies are investigated. Results obtained on the resolvent of the full hard-sphere and Maxwell Boltzmann equations establish qualitatives similarity in behavior between the classical Boltzmann equations of rarefied gases and their degenerate kernel approximations. This similarity holds also for the analytic continuation into the continuous spectrum of the Boltzmann operators. Comparison is made with the Grad 1,2 and Sirovich 3,4 theories.
Attrition From Premedical Studies Among Latinas: Case Studies

Minorities are significantly underrepresented in the U.S. physician workforce. Female minorities wishing to become doctors face additional gender barriers, since women who enter college with the desire of becoming physicians are more likely than men to exit programs of undergraduate studies (“premed studies”) that lead to medical school. To explore the factors that may cause minority women to lose interest in a medical career, in-depth one-to-one interviews were conducted during the first quarter of freshman year with minority women who had said prior to matriculating that they were interested in pursuing a career in medicine. Interviews with seven Latinas were analyzed to develop grounded theory to identify potential causes of attrition from premedical studies within this underrepresented group. Findings point to the importance of linking such students into premedical-student support systems at the beginning of their freshman year to retain them in the premedical pipeline and argue that the mechanisms th...
Pupil imaging with a high sensitivity, LWIR focal plane array

We describe an integrated sensor assembly serving as both a component technology demonstration and a potential means of detecting distant point sources of infrared radiation. The objective of the demonstration was to show that usefully long integration times could be achieved with a low-background and well capacity, LWIR focal plane array optimized for use with cooled optics in space. The system controls extraneous background radiation with a small (150 μm) cooled pinhole that nevertheless transmits all the radiation of a point source collected by the fore-optic. Broad waveband response (~3 to 12 μm) results from optimization of the fore-optic for both MW and LWIR, as well as from a broadband anti-reflection coating on the field lens that is used at the pinhole to reimage the entrance aperture and its surrounding cold stop. Integration times in excess of 10 msec have been achieved for room temperature backgrounds with the FPA cold stage operated at 50 Kelvin, and noise performance has been bracketed with single frames of data collected over several integration times and over several minutes duration. However, anomalous signal behavior has been observed as the temperature of a remote blackbody increases. Although operation to date has been with a lower operability, engineering grade FPA, plans are to eventually upgrade to a higher quality device.
MECHANISM OF ADENOSINE TOXICITY TO ADENOSINE KINASE DEFICIENT MAMMALIAN CELLS: 30

Somatic cell genetics has been used to probe the mechanism of adenosine (Ado) toxicity to mammalian cells deficient in Ado deaminase and Ado kinase. Ado resistant clones of an Ado kinase deficient murine lymphoblastoid cell line (R1.1) were isolated and characterized. In deoxycoformycin supplemented medium, the mutant clones were 10-30 fold more resistant than parental cells to the anti-proliferative actions of Ado, 3-deaza-Ado, carbocyclic-Ado, adenine, 5'-methylthioadenosine, and several other Ado analogs. The mutants were normally sensitive to the toxic effects of deoxyadenosine and adenine arabinoside. Levels of S-adenosylmethionine (SAM) were 50 pmols/106 cells in the parental line, compared to 250-350 pmois/106 cells in the mutant. Methionine adenosyitransferase activity was 1.5-3.2 fold higher in the Ado-resistant cells than in parental lymphoblasts, and varied inversely with the medium methionine concentration. Ado induced the accumulation of equivalent amounts of S-adenosylhomocystelne (SAH) in both cell types. However, the SAH to SAM ratio in the Ado-resistant mutants never exceeded 0.1. These results show that (i) methionine adenosyltransferase is an inducible enzyme in mammalian cells, (ii) the toxic effects of Ado, adenine, and many Ado analogs, can be averted by increasing the velocity of SAM synthesis.
Self-Policing Statutes: Do They Reduce Pollution and Save Regulatory Costs?

State-level statutes provide firms that engage in environmental self-audits, and that self-report their environmental violations, a variety of regulatory rewards, including "immunity" from penalties and "privilege" for information contained in self-audits. This article studies a panel of state-level industries from 1989 through 2003, to determine the effects of the different types of statutes on toxic pollution and government inspections. We find that, by encouraging self-auditing, privilege protections tend to reduce pollution and government enforcement activity; however, sweeping immunity protections, by reducing firms' pollution prevention incentives, raise toxic pollution and government inspection oversight. The Author 2011. Published by Oxford University Press on behalf of Yale University. All rights reserved. For Permissions, please email: journals.permissions@oup.com, Oxford University Press.
How to Correlate Membrane Interaction Kinetics with Structural Measurements

Studies of membrane problems are often controversial because there is no ideal experimental method for membrane studies. Membrane studies in solution are typically macroscopic observations containing no molecular level information. On the other hand samples that produce molecular level information are not single membranes in solution. Thus there is no direct link between the microscopic structural measurements and the actions in a membrane. Here we show that a combination of aspirated GUV and X-ray diffraction experiments is capable of providing a correlated link between macroscopic observation and molecular measurement. The action of peptides or drugs on a membrane can be observed by the membrane area change in an aspirated GUV. The bound states of peptides or drugs cause membrane thickness changes that can be measured precisely by X-ray diffraction. The incompressibility of the hydrocarbon chains equates the fractional membrane area change ΔA/A to the fractional membrane thickness change Δh/h. The equality directly links these two experiments, one on the micron scale and another on the Angstrom scale. We demonstrate the utility of this method by the action of melittin, a prototype AMP. Melittin bound to a lipid bilayer causes membrane thinning in proportion to P/L until P/L reaches a P/L∗; further binding has little effect on membrane thickness. In DOPC, P/L∗∼1/75 and the thinning at P/L∗ is ‒Δh/h=5.6%. Neutron in-plane scattering and OCD showed membrane pores were formed when P/L exceeded P/L∗. In the aspirated GUV experiment, we monitored melittin binding, membrane area change and molecular leakage all at the same time. Spontaneous melittin binding to the GUV caused its membrane expansion. Molecular leakage occurred when ΔA/A=5.7%. Many conclusions can be drawn from the consistency between the kinetic experiment and equilibrium experiment. Examples on other peptides and drugs are also shown.
Data simulation techniques for reactions of the form X (a, bc) Y,…

Abstract A data simulation technique is presented for use in the analysis of multi-particle final states when two of the particles are detected in coincidence. Experimental effects which broaden the energy and angular resolution are folded into the theoretical predictions to allow direct comparisons with the experimental data.
Spatial Dynamics and Control of Cell Differentiation

Understanding regulatory networks requires taking into account their controls and their spatiotemporal dynamics. We are probing these in experiments on the C. elegans germ line that target organ-level regulation of differentiation, and that leverage image segmentation workflows we have developed. In this talk I will explore the role of Notch signaling as a control of the germline regulatory network, and the role of diffusion in shaping the dynamics of the network. These are first steps towards our final goal of gaining a systems-level understanding of the C. elegans germline regulatory network.
Plasma Volume Changes With an Acute Bout of High-Intensity Exercise in Men With Chronic Congestive Heart Failure Secondary to Coronary Artery Disease☆

We assessed plasma volume changes at peak exercise in 17 nonedematous men with chronic congestive heart failure due to coronary artery disease. Our findings suggest that acute exercise is associated with transient decreases in plasma and blood volume in these patients, similar in magnitude to those reported for healthy adults at peak exercise.
Roles of NF-κB and 26 S Proteasome in Apoptotic Cell Death Induced by Topoisomerase I and II Poisons in Human Nonsmall Cell Lung Carcinoma

Abstract Activation of signaling pathways after DNA damage induced by topoisomerase (topo) poisons can lead to cell death by apoptosis. Treatment of human nonsmall cell lung carcinoma (NSCLC-3 or NSCLC-5) cells with the topo I poison SN-38 or the topo II poison etoposide (VP-16) leads to activation of NF-κB before induction of apoptosis. Inhibiting the degradation of IκBα by pretreatment with the proteasome inhibitor MG-132 significantly inhibited NF-κB activation and apoptosis but not DNA damage induced by SN-38 or VP-16. Transfection of NSCLC-3 or NSCLC-5 cells with dominant negative mutant IκBα (mIκBα) inhibited SN-38 or VP-16 induced transcription and DNA binding activity of NF-κB without altering drug-induced apoptosis. Regulation of apoptosis by mitochondrial release of cytochrome c and activation of pro-caspase 9 followed by cleavage of poly(ADP-ribose) polymerase by effector caspases 3 and 7 was similar in neo and mIκBα cells treated with SN-38 or VP-16. In contrast to pretreatment with MG-132, exposure to MG-132 after SN-38 or VP-16 treatment of neo or mIκBα cells decreased cell cycle arrest in the S/G2 + M fraction and enhanced apoptosis compared with drug alone. In summary, apoptosis induced by topoisomerase poisons in NSCLC cells is not mediated by NF-κB but can be manipulated by proteasome inhibitors.
Laser multiphoton dissociation and multiphoton ionization of VOCl3

Abstract Laser multiphoton dissociation—multiphoton ionization (MPD—MPI) spectra of VOCl 3 have been obtained in the ranges 430–440 and 380–390 nm. V + and VO + were the only ions produced by the pulsed dye laser. We find that both the V + and VO + spectra are continuous and structureless. The laser power dependence of the production of V + ions is substantially stronger than that of VO + in those wavelength ranges. These results are interpreted in terms of a novel pathway for formation of V + by photo-dissociation of VO + .
A Pain Research Agenda for the 21st Century

Chronic pain represents an immense clinical problem. With tens of millions of people in the United States alone suffering from the burden of debilitating chronic pain, there is a moral obli- gation to reduce this burden by improving the understanding of pain and treatment mechanisms, developing new therapies, optimizing and testing existing therapies, and improving access to evidence-based pain care. Here, we present a goal-oriented research agenda describing the American Pain Society's vision for pain research aimed at tackling the most pressing issues in the field. Perspective: This article presents the American Pain Society's view of some of the most important research questions that need to be addressed to advance pain science and to improve care of patients with chronic pain. a 2014 by the American Pain Society
Homogenization principles and their application to continuum damage mechanics

The concept of homogenization is utilized herein to develop simplified methodologies for predicting the response of solids that develop multi-scale damage. This methodology is cast within a computational framework in order to produce efficient algorithms for a variety of media including granular and layered composites. Examples are given to exemplify the usefulness of this approach.
Improving proteomics mass accuracy by dynamic offline lock mass.

Several methods to obtain low-ppm mass accuracy have been described. In particular, online or offline lock mass approaches can use background ions, produced by electrospray under ambient conditions...
Redefining food: the standardization of products and production in Europe and the United States, 1880–1914

This article analyzes the interrelationship between expert systems and the creation of public trust in food production in the late nineteenth and early twentieth centuries, focusing on the roles of scientific knowledge and elites in academia, government, and business. The nutrient paradigm of the mid nineteenth century played a crucial part in this history, facilitating new practices of control and standardization based on measurable, empirical ‘facts.’ This article compares the different approaches, power constellations, and results of the struggle for improved and reliable food quality in Germany, Austria, Switzerland, and the USA. Scientists, especially chemists, the food industries, and public authorities at the local, regional, and federal levels established a structure of science‐based standardization and trust‐building, which acted on behalf of the consumer in enforcing their own ‘objective’ ideas about safe products and additives.
The inferior colliculus of GEPRs contains greater numbers of cells that express glutamate decarboxylase (GAD67) mRNA

Previous studies have shown significantly greater GABA levels and numbers of GABAergic neurons in the central nucleus of the inferior colliculus (ICCN) of genetically epilepsy-prone rats (GEPR-9s). In the present study, in situ hybridization and emulsion autoradiographic techniques were used to determine whether there are also elevated numbers of ICCN cells that contain the 67-kD form of mRNA for the GABA synthesizing enzyme, glutamate decarboxylase (GAD), in GEPR-9s as compared to normal Sprague-Dawley (SD) rats. Hybridization with a 35S-labeled RNA probe complementary to a span of monkey GAD mRNA labeled cells throughout the brain including the ICCN. Labeled cells in the ICCN appeared to be of different sizes that corresponded with previous descriptions of GABAergic neurons from immunocytochemical studies. In the GEPR-9s, a larger number of GAD67 cRNA labeled neurons was observed in the ICCN as compared to SD rats. The external nucleus of the inferior colliculus was also found to contain significantly greater numbers of GAD67 cRNA labeled neurons whereas in the frontal cortex, a region of the brain that is not required for audiogenic seizure activity in GEPR-9s, there were no significant differences in hybridization between GEPR-9s and SD rats. Interestingly, within the superficial layers of the superior colliculus there was a higher density of hybridization in GEPR-9s than in SD rats indicating higher levels of GAD expression.(ABSTRACT TRUNCATED AT 250 WORDS)
On stochastic automata and languages

Abstract This paper is mainly concerned with two problems in the area of stochastic languages. For the λ-stochastic languages, a flexible stochastic experimental procedure based on Chebyshev's inequality is proposed. Then, the class of maximum-likelihood stochastic languages is defined on the basis of the maximum-likelihood final-state distribution. Properties of this class of languages and its relationship to λ-stochastic languages are investigated.
In Vivo Regulation of TGF-β by R-Ras2 Revealed through Loss of the RasGAP Protein NF1

Ras superfamily proteins participate in TGF-β-mediated developmental pathways that promote either tumor suppression or progression. However, the specific Ras proteins, which integrate in vivo with TGF-β signaling pathways, are unknown. As a general approach to this question, we activated all Ras proteins in vivo by genetic deletion of the RasGAP protein Nf1 and examined mice doubly deficient in a Ras protein to determine its requirement in formation of TGF-β-dependent neurofibromas that arise in Nf1-deficient mice. Animals lacking Nf1 and the Ras-related protein R-Ras2/TC21 displayed a delay in formation of neurofibromas but an acceleration in formation of brain tumors and sarcomas. Loss of R-Ras2 was associated with elevated expression of TGF-β in Nf1-deficient Schwann cell precursors, blockade of a Nf1/TGFβRII/AKT-dependent autocrine survival loop in tumor precursor cells, and decreased precursor cell numbers. Furthermore, the increase in size of sarcomas from xenografts doubly deficient in these genes was also found to be TGF-β-dependent, in this case resulting from cell nonautonomous effects on endothelial cells and myofibroblasts. Extending these findings in clinical specimens, we documented an increase in TGF-β ligands and an absence of TGF-β receptor II in malignant peripheral nerve sheath tumors, which correspond to tumors in the Nf1-deficient mouse model. Together, our findings reveal R-Ras2 as a critical regulator of TGF-β signaling in vivo.
On the spectrum of the Bergman-Hilbert matrix

Abstract The Bergman-Hilbert matrix is the matrix of the Hilbert-Hankel operator on the Bergman space L2a of the disk. We obtain estimates on its norm and prove the existence of eigenvalues.
Facilitating the Culture of Mammalian Nerve Cells with Polyelectrolyte Multilayers

When neuron-like cells (NLCs) derived from pluripotent embryonal carcinoma cells (P19) are cultured on bare tissue culture substrates, they require a monolayer of fibroblast cells to exhibit normal neurite outgrowth, behavior typical of neuronal cultures. However, substrate treatment with polyelectrolyte multilayers (PEMs) composed of poly(allylamine hydrochloride) (PAH) and poly(styrenesulfonic acid) (PSS) significantly improved these cultures. Cell morphology was more spread, indicative of healthy cells, and direct attachment of neuronal cell bodies to the treated surface was observed. Neuronal outgrowth across the surface was not dependent on an underlying fibroblast monolayer with the PEMs surface treatment. Additionally, the PEMs surface treatment can be used to condition various surfaces, facilitating neuronal cultures on surfaces which are natively hydrophilic (tissue culture polystyrene) or hydrophobic (poly(dimethylsiloxane), PDMS). Microfluidic networks were used to micropattern the PEMs onto PDMS, resulting in confined regions of cellular attachment and directed neuronal outgrowth. The ability of PEMs to encourage NLC attachment without supporting cells to a variety of surfaces and surface geometries greatly simplifies neuronal culture methodology and enables neuronal investigations in new environments.
Metacontrast as a function of the spatial frequency composition of the target and mask.

Abstract Metacontrast masking as a function of spatial frequency components of the stimuli was studied. The targets and masks were rectangular windows in which luminance was modulated sinusoidally in the horizontal dimension. The masking functions obtained with these stimuli were quite similar to functions obtained in more typical metacontrast studies. Contrary to predictions by current models of spatial frequency channels or edge mechanisms, the variation in optimal masking for different stimulus conditions did not correspond to the similarity of spatial frequency components of the target and mask, to the Sustained-Transient hypothesis, or to the luminance near the edge of the mask.
Localization in general one dimensional random systems, I. Jacobi matrices

We consider random discrete Schrodinger operators in a strip with a potentialVω(n, α) (n a label in ℤ and α a finite label “across” the strip) andVω an ergodic process. We prove thatH0+Vω has only point spectrum with probability one under two assumptions: (1) Theconditional distribution of {Vω(n,α)}n=0,1;allα conditioned on {Vω}n≠0,1;allα has an absolutely continuous component with positive probability. (2) For a.e.E, no Lyaponov exponent is zero.
Laser direct-write of metal patterns for interconnects and antennas

The use of direct-write techniques in the design and manufacture of interconnects and antennas offers some unique advantages for the development of next generation commercial and defense microelectronic systems. Using a laser forward transfer technique, we have demonstrated the ability to rapidly prototype interconnects and various antenna designs. This laser direct-write process is compatible with a broad class of materials such as metals and electronic ceramics and its capable of depositing patterns of any of these materials over non-planar surfaces in a conformal manner. The laser direct-write process is computer controlled so as to allow any given design to be easily modified and adapted to a particular application. To illustrate the potential of this technique, examples of metal lines on laser micromachined polyimide substrates for interconnect applications, are discussed and evaluated. In addition, examples of simple planar and conformal antennas are provided to demonstrate how this technique can influence current and future microelectronic device applications.
Infinite-dilution viscoelastic properties of tobacco mosaic virus

The storage and loss shear moduli, G′ and G″, have been measured for dilute solutions of unaggregated and aggregated tobacco mosaic virus samples in glycerol–water mixtures, by the Birnboim–Schrag multiple-lumped resonator modified for use with aqueous solvents. The frequency range was 100–5800 Hz, the concentration range 0.6–2.1 × 10−3 g/ml, and the temperatures 25.0° and 37.8°C. The number-average and weight-average molecular weights of the aggregated sample were estimated as 1.4 and 2.0 × 108, respectively, from electron microscopy. The extrapolated intrinsic moduli [G′] and [G″] were compared with the predictions of the Kirkwood–Auer theory for rigid rodlike molecules. For the unaggregated sample, the frequency dependence of [G′] and [G″] agreed well with the theory assuming the intrinsic viscosity to be 27 ml/g, though the asymptotic limit of [G′]M/RT at higher frequencies was slightly larger than the theoretical value of 3/5. For the aggregated sample, the data agreed with theory for rigid rods as modified to account for molecular-weight distribution.
Vote Selling, Voter Anonymity, and Forensic Logging of Electronic Voting Machines

Much recent work has focused on the process of auditing the results of elections. Little work has focused on auditing the e-voting systems currently in use. The facilities for doing the former include the voter-verified paper audit trail; unfortunately, that VVPAT is not particularly helpful in tracking down the source of errors within e-voting systems. This paper discusses the need for a detailed forensic audit trail (FAT) to enable auditors to analyze the actions of e-voting systems, in order to demonstrate either the absence of problems or to find the causes of problems. We also discuss methods to prevent the use of the FAT as a covert channel for violating the necessary properties of secrecy of the ballot, so voters cannot sell their votes, and anonymity of the ballot, so a third party cannot associate a particular ballot with the voter who cast it.
Digital Textbooks: The Next Paradigm Shift in Higher Education?

in recent years, college instructors have begun to abandon traditional approaches to instruction, which merely transfer knowledge from faculty to students, for cutting-edge strategies, which allow students to construct their own learning. this change in instructional strategy has also brought about a change in the tools which are used for instruction. As students gain more control over their learning, they also want to have more control over the tools that guide their learning. in many ways, the traditional textbook is no longer satisfying the needs of today’s students. consequently, students and faculty members are beginning to look for an alternative. digital textbooks provide promise, but will they replace their print counterparts? the following article attempts to answer this question by exploring the evolution of textbooks from medieval times to the present day. the authors suggest that digital textbooks have a promising future in higher education.
Population differences in predation on Batesian mimics in allopatry with their model: selection against mimics is strongest when they are common

Batesian mimicry evolves when a palatable species, the "mimic," resembles a dangerous species, the "model," because both receive protection from predation. Yet, this protection should break down where the model is absent, because predators in such areas would not be under selection to avoid the model.Here,we test this prediction in a coral snake mimicry complex. We exposed plasticine replicas of milk snakes that closely mimic coral snakes to natural predators to determine if good mimetic milk snakes are preferentially attacked in allopatry with their model. Moreover, we evaluated whether attack rates on these replicas varied among three different allopatric regions that differed in the type of mimic found locally (i.e., good mimic, poor mimic, or no mimic). When all three regions were considered together, mimics were not preferentially attacked. When regions were analyzed separately, however, attacks on mimics were significantly greater than randomness only where good mimics were found. These variable levels of predation on good mimics might reflect frequency-depen- dent (i.e., apostatic) predation. In allopatric regions where good mimics are present, predators might have learned or evolved preferences for conspicuous, palatable prey that they encounter frequently.By contrast, in allopatric regions where good mimics are absent, predators might not have learned or evolved preferences for novel phenotypes. Thus, when predation is frequency-dependent, as long as good mimics are rare, they might not experience elevated levels of predation in allopatry with their model as predicted by the Batesian mimicry hypothesis.
Learning polarity from structure in SAT

Few instances of a computational problem are sui generis; most instead belong to some distribution of related instances, and information gained from solving past instances from the distribution may be leveraged to solve future instances more efficiently. Algorithm portfolio methods and algorithm synthesis systems are two examples of this idea. This paper proposes and demonstrates a third approach.
Failure of a Constrained Acetabular Prosthesis of a Total Hip Arthroplasty. A Report of Four Cases

Instability with recurrent dislocation after total hip arthroplasty is a formidable challenge to the orthopaedic surgeon. The prevalence of dislocation has been reported to be 1 to 8 per cent in series ranging from 300 to 10,500 total hip arthroplasties4-6,10,16. Relative risk factors for dislocation include a previous operation on the hip, the type of operative approach used, the selection and orientation of the components, the method of postoperative management, an altered neuromuscular status, and lack of patient cooperation3-6,9,10,12,16. The use of a constrained acetabular polyethylene liner provides the orthopaedic surgeon with another option with which to address the problem of instability. We have managed four patients who had failure of a revision total hip arthroplasty involving an S-ROM constrained acetabular polyethylene liner (Joint Medical Products, Stamford, Connecticut) (Figs. 1-A and 1-B). Two of the failures were associated with a fracture of the constraining ring on the neck of the liner, but only one of the two resulted in dislocation or clinical instability. The other two failures occurred in hips in which the constraining ring was intact; in both instances, the femoral head was dislocated but the acetabular shell and liner remained in place. We present two case reports that are representative of each type of failure. These failures illustrate the potential limitations in the clinical utility of the constrained acetabular liner. Although dislocations involving a non-constrained liner usually can be treated initially with closed reduction, those involving a constrained liner necessitate open reduction. Figs. 1-A and 1-B: Photographs of the S-ROM total hip arthroplasty system (Joint Medical Products, Stamford, Connecticut). Fig. 1-A: The acetabular components. Fig. 1-B The assembled constrained acetabular component and the femoral component. CASE 1. A …
Concurrent Validity of the Wechsler Abbreviated Scale of Intelligence and the Kaufman Brief Intelligence Test among Psychiatric Inpatients

This study examined the convergent and discriminant validity of the Wechsler Abbreviated Scale of Intelligence and the Kaufman Brief Intelligence Test for 85 psychiatric inpatients. The correlation between the WASI Full Scale and K-BIT Composite IQ scores was significant (r = .89, p < .001). Multitrait-multimethod analysis of the subtest scores showed that the K-BIT had higher internal consistency for its two subtests but, therefore, less differentiation of cognitive functioning than the brief Wechsler scale, as would be expected due to the larger number and diversity of the latter subtests. Correlations among the Wechsler scale subtests were lower than among those for the K-BIT, so the former may tap different cognitive functions and yield more clinically useful information than the latter. This brief Wechsler scale appears to be a valid screening measure of verbal, performance. and general intellectual ability for use with an inpatient psychiatric population when considerations of the setting or patient preclude administration of a longer measure of intellectual ability.
How living wills can help doctors and patients talk about dying.

Papers p 1640 Many people are unaware of living wills but are highly interested once they hear about them. In this week's BMJ Schiff et al (p 1640) find that elderly inpatients are confused by the term living will, but most would welcome the chance to discuss issues about facing the end of life, and many would want to limit their health care if they were terminally ill.1 An assessment of the understanding of living wills in the United States some time ago found a similar state of affairs.2 This juxtaposition of ignorance and interest raises an important question: what is this apparent appetite to discuss and prepare for dying? When lawyer Louis Kutner proposed the notion of a living will in 1969, he was responding to the fear that technology was driving doctors to impose life sustaining treatment on patients who might not want it. The living will was seen as a simple device to allow patients to say no, even if they were too ill to …
Adaptive transmitting antenna methods for multipath environments

Adaptive transmitting antenna arrays hold great promise for increasing the capacity of mobile radio networks by reusing a channel among several users. To reuse bandwidth, a transmitting antenna array requires feedback information from the mobile receivers in order to track changes in the multipath environment. When the mobile is moving rapidly, the required feedback rates can become significant. We present a new method for transmission beamforming, which, by exploiting the subspace structure present in the spatial channel, requires much lower feedback data rates than previous methods.