cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling of propagation and cross-talk in interconnects using SPICE

The purpose of this work is to present a method by which the CAD tool SPICE along with a circuit parameter calculating routine can be used to find both the frequency-domain and time-domain responses of a nonuniform multiconductor transmission line using ordinary circuit element models which already exist in SPICE. A lumped-element equivalent circuit model for a possibly nonuniform multiconductor transmission line is presented which can be easily used in SPICE to expand its validity. To verify this model, several examples with modeling and experimental results in both frequency and time domain are given and discussed. It is shown that the results obtained by this method are in good agreement with the experiment results. >
Role of peroxisomal oxidation in the conversion of arachidonic acid to eicosatrienoic acid in human skin fibroblasts.

Abstract Human skin fibroblasts converted [5,6,8,9,11,12,14,15- 3 H]arachidonic acid ([ 3 H]20:4) to eicosatrienoic acid (20:3), but appreciable amounts of radiolabeled 20:3 were not detected in corresponding incubations with [1- 14 C]20:4. This indicates that the main pathway for synthesizing 20:3 from arachidonic acid in the fibroblast involves oxidative removal of the carboxyl group of arachidonic acid. Fibroblasts deficient in long-chain acyl coenzyme A dehydrogenase (LCAD) converted [ 3 H]20:4 to [ 3 H]20:3. However, Zellweger fibroblasts that are deficient in peroxisomal fatty acid oxidation did not, indicating that the oxidative removal of the carboxyl group occurs in the peroxisomes. [ 3 H]Hexadecatrienoic acid (16:3) was the main product that accumulated when [ 3 H]20:4 was incubated with normal, LCAD deficient, and very long-chain acyl coenzyme A dehydrogenase (VLCAD) deficient fibroblasts, but Zellweger fibroblasts did not form this product. Normal fibroblasts converted [ 3 H] 16:3 to radiolabeled 20:3 and arachidonic acid. These findings suggest that some of the 16:3 produced from arachidonic acid by peroxisomal β-oxidation can be recycled and that this recycling process constitutes a novel pathway for the conversion of arachidonic acid to 20:3 in human fibroblasts.
Launch processing for Spacelab 1

The final integration of Spacelab payloads with the Shuttle is described. Attention is given to launch processing planning, schedules, quality control, and problem reports and configuration maintenance. Also covered are the integration and checkout of individual and combined experiments, mounting the end cones, attachment of the transfer tunnel, and inclusion of an extra experiments pallet. The entire Spacelab module was subjected to a full systems simulation before deliverance to the Orbiter bay. Modular parts that were transferred from building-to-building were placed in sealed containers filled with a purged atmosphere during transport.
Structure and function of steroid dehydrogenases involved in hypertension, fertility, and cancer

Short-chain dehydrogenase reductase (SDR) enzymes influence mammalian reproduction, hypertension, neoplasia, and digestion. The three-dimensional structures of two members of the SDR family reveal the position of the conserved catalytic triad, a possible mechanism of keto-hydroxyl interconversion, the molecular mechanism of inhibition, and the basis for selectivity. Glycyrrhizic acid, the active ingredient in licorice, and its metabolite carbenoxolone are potent inhibitors of bacterial 3 alpha, 20 beta-hydroxysteroid dehydrogenase (3 alpha, 20 beta-HSD). The three-dimensional structure of the 3 alpha,20 beta-HSD carbenoxolone complex unequivocally verifies the postulated active site of the enzyme, shows that inhibition is a result of direct competition with the substrate for binding, and provides a plausible model for the mechanism of inhibition of 11 beta-hydroxysteroid dehydrogenase and 15-hydroxyprostaglandin dehydrogenase by carbenoxolone. The structure of human 17 beta-hydroxysteroid dehydrogenase type 1 (17 beta-HSD) suggests the details of binding of estrone and 17 beta-estradiol in the active site of the enzyme and the possible roles of various amino acids in the catalytic cleft. The SDR family includes over 50 proteins from human, mammalian, insect, and bacterial sources. Only five residues are conserved in all members of the family, including the YXXXK sequence. X-ray crystal structures of five members of the family have been completed. When the alpha-carbon backbone of the cofactor binding domains of the five structures are superimposed, the conserved residues are at the core of the structure and in the cofactor binding domain, but not in the substrate binding pocket.
Results of Penetrating Keratoplasty For Aphakic And Pseudophakic Bullous Keratopathy

We retrospectively studied 61 consecutive cases of penetrating keratoplasty performed for aphakic bullous keratopathy or pseudophakic bullous keratopathy. After keratoplasty, the mean visual acuities of both groups of patients improved significantly from preoperative levels (P less than .0001). One year after keratoplasty, 18 eyes had visual acuities of 20/40 or better. Twelve of the 24 eyes followed up for at least two years after surgery had visual acuities of 20/40 or better. The mean visual acuities for the eyes with aphakic bullous keratopathy and the eyes with pseudophakic bullous keratopathy were not significantly different at either one or two years after keratoplasty. Cystoid macular edema (11 eyes) and glaucoma (12 eyes) were the most common causes of visual acuities worse than 20/40. There were no significant differences in the incidences of these complications in the group with aphakic bullous keratopathy and in the group with pseudophakic bullous keratopathy. Intraocular lens removal did not significantly affect either visual acuity or macular complications after keratoplasty.
Predicting failure of outpatient laparoscopic cholecystectomy.

Abstract Background: Outpatient laparoscopic cholecystectomy (LC) is safe and feasible, but factors related to the failure of outpatient surgery are poorly defined. We hypothesized that patients in whom same day discharge (SDD) is unlikely may be identified preoperatively. Methods Three hundred eighty-seven consecutive patients scheduled for elective LC were prospectively enrolled in an outpatient clinical pathway. Results In all, 269 (70%) patients successfully underwent outpatient LC. Factors related to failure of SDD were age, American Society of Anesthesiology (ASA) class, surgery start time, and duration of surgery. Body mass index, liver function tests, and ultrasound findings did not predict failure of SDD. Three factors were able to predict more than 50% failure of SDD: age more than 50 years, ASA class 3 or more, and surgery start time later than 1:00 pm Conclusions: Outpatient LC is feasible in a large county hospital. These data may be used in scheduling cases and counseling patients.
An Experiment with Glycerol-Frozen Red Blood Cells Stored at -80°C for up to 37 years

Background and Objectives: Red cells frozen using 40% W/V glycerol are currently FDA approved for frozen storage at –80°C for up to 10 years. Materials and Methods:</i&g
Quality of life in a prospective cohort of elderly women with and without cancer

BACKGROUND: Quality of life (QOL) is an important issue for cancer survivors; few studies are able to consider elderly populations, address long-term survival (≥5 years), examine different cancers, or include a valid noncancer comparison group. METHODS: The authors assessed QOL in 2004 among women participating in the Iowa Women's Health Study, a prospective cohort of older women followed since 1986. Cancer occurrence during follow-up was identified through the State Health Registry of Iowa. The authors compared unadjusted, and age- and comorbidity-adjusted mean scores for 8 Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) scales among women with and without cancer by all cancer types, stage, and survival. Analyses were repeated after excluding women who developed a second primary cancer or reported cancer treatment in 2004. RESULTS: Among 17,385 respondents aged 71-89 years, 2717 (16.6%) had been diagnosed with cancer since 1986. Compared with women without cancer, survivors fared worse on the General Health scale, regardless of cancer type (except colorectal), stage, or survival. Except for lower scores among the longest survivors, Mental Health scores did not differ significantly between women with and without cancer. Women with genitourinary, lung, hematopoietic, lymphoma, or other gastrointestinal cancers, with cancer at the distant stage, or who survived at least 10 years consistently experienced significantly lower QOL scores than cancer-free women for most scales. CONCLUSIONS: Differences in QOL depended upon the specific SF-36 scale and which aspect of cancer survivorship was examined. These findings underscore the complexity of factors contributing to QOL among cancer survivors. Cancer 2009;115(18 suppl):4283–97. © 2009 American Cancer Society.
Opposing roles of ZYXIN/LPP ACTA repeats and the LIM domain region in cell-cell adhesion

Cadherins mediate cell-cell adhesion by linking cell junctions to actin networks. Although several actin regulatory systems have been implicated in cell-cell adhesion, it remains unclear how such systems drive cadherin-actin network formation and how they are regulated to coincide with initiation of adhesion. Previous work implicated VASP in assembly of cell-cell junctions in keratinocytes and the VASP-binding protein zyxin colocalizes with VASP at cell-cell junctions. Here we examine how domains in zyxin and its relative LPP contribute to cell-cell junction assembly. Using a quantitative assay for cell-cell adhesion, we demonstrate that zyxin and LPP function to increase the rate of early cell-cell junction assembly through the VASP-binding ActA repeat region. We also identify the LIM region of zyxin and LPP to be a regulatory domain that blocks function of these proteins. Deletion of the LIM domains drives adhesion and increases VASP level in detergent insoluble cadherin-actin. Dominant-negative zyxin/LPP mutants reduce the rate of adhesion, lower VASP levels in detergent-insoluble cadherin-actin networks, and allow for the accumulation of capping protein at cell-cell contacts. These data implicate the LIM domains of zyxin and LPP in regulating cell-cell junction assembly through VASP.
Flow-induced crystallization precursor structure in high molecular weight isotactic polypropylene (HMW-iPP)/low molecular weight linear low density polyethylene (LMW-LLDPE) binary blends

Abstract The formation of initial crystallization precursor induced by flow was investigated by synchrotron-based wide- and small-angle X-ray scattering techniques (WAXS/SAXS), using polymer blends consisting of high molecular weight isotactic polypropylene (HMW-iPP) and low molecular weight linear low density polyethylene (LMW-LLDPE) as model systems. LMW-LLDPE, the dominant component, served as the amorphous matrix. Crystallization behavior of the blends with three different HMW-iPP concentrations, i.e., 3, 6 and 9 wt%, were examined at temperatures higher than the blends' cloud points, in a time-resolved manner. It was found that the formation of a flow-induced precursor of crystallization was strongly influenced by the concentration of HMW-iPP in the blends. The blend with low HMW-iPP content (3 wt%) was not able to form a shear-induced crystalline structure. As the concentration of HMW-iPP increased, crystallization kinetics, crystallinity, and lamellar orientation were greatly enhanced.
Energy-filtered imaging with electrostatic optics for photoelectron microscopy

Abstract A simple first-order theory shows that energy-filtered imaging can be accomplished using spherical-sector capacitors without a restriction on the deflection angle of the sector. The geometrical requirements for placement of coupling lenses to achieve this result are derived using a virtual-image concept and are illustrated for the 90° and 180° sector cases. The dispersion of the sector capacitor introduces aberrations which affect the image quality. These aberrations are discussed analytically and with the aid of ray-tracings. It is found that these aberrations can be made small enough to be negligible in the practical operation of an energy-filtered photoelectron microscope.
Studies to improve fixation of human nerves V. Effect of temperature, fixative and CaCl2 on density of microtubules and neurofilaments

Utilizing morphometry of electron micrographs of nerves of rat fixed with different schedules of fixation it was concluded that: irrespective of the fixative, fixation at low temperature is associated with markedly low densities of microtubules (MT) of myelinated and of unmyelinated fibers; of the various fixatives tested 2% glutaraldehyde in 0.1 M cacodylate buffer without 0.025 M CaCl2 was associated with the highest density of MT of myelinated fibers and the addition of 0.025 M CaCl2 to a 2% glutaraldehyde fixative solution is associated with abnormally low densities of MT in myelinated and unmyelinated fibers. An effect of temperature, fixative and added CaCl2 on neurofilaments density was not demonstrated. Using the criterion of density of MT and assuming that these studies on rat nerves can be applied to biopsied nerve of man, fixation of human nerves should be at room or body temperature, and the fixative solution should not contain 0.025 M CaCl2.
Radiation response of fiber optic waveguides in the 0.4 to 1.7 μ region

The response of fiber optic waveguides to ionizing radiation has been studied. Measurements of the growth and decay of the radiation-induced loss at 0.82μ have revealed that fibers with low OH are more susceptible to damage than those with high OH. The addition of P to Ge-doped silica core fibers has been found to suppress an intense transient absorption. Spectral measurements of the radiation-induced absorption between 0.4 - 1.7μ have shown an increase in the OH overtone and combination band intensity with irradiation so that the induced loss at 1.3μ is actually less in the low OH content silica core fibers than in the high OH content fibers. Real time spectral measurements of the damage following a pulsed irradiation have lead to an identification of the absorption bands and damage mechanisms responsible for the radiation-induced absorption.
Nuclear cusps in the HSF electron density

Abstract The Hiller-Sucher-Feinberg (HSF) identity provides an alternative definition for the electron density. The behavior of the HSF electron density in the vicinity of nuclei is analyzed. It is shown that the HSF density possesses nuclear cusps at which its gradient is discontinuous. The discontinuities in the HSF density gradient satisfy a simple equation analogous to Kato's electron-nuclear cusp condition. However, in contrast to Kato's condition, the electron-nuclear cusp condition is satisfied by HSF densities originating from both exact and approximate electronic wavefunctions. Several numerical examples are presented to illustrate this property of the HSF electron density.
Parathyroid Hormone Regulates the Expression of the Receptor Protein Tyrosine Phosphatase, OST-PTP, in Rat Osteoblast-Like Cells*

Bone remodeling requires regulated tyrosine phosphorylation mediated by specific protein tyrosine kinases, such as c-src and c-fms, and to date, unknown protein tyrosine phosphatases (PTPs). We previously reported the isolation of a novel bone-specific receptor PTP, named osteotesticular PTP (OST-PTP), which is regulated during osteoblast differentiation and after exposure to PTH. To determine the relevance of this PTH regulation, we characterized the PTH-induced increase in OST-PTP messenger RNA (mRNA) in UMR 106 cells in comparison with PTH effects on a related receptor PTP and a PTH regulated gene, rat collagenase. Treatment of cells with rat PTH 1-34 (rPTH) resulted in a dramatic concentration and time-dependent increase in OST-PTP mRNA with a threshold at 4 h (= or < 1nM rPTH) and maximal response of 6- 10-fold above control levels at 8 h (100 nM rPTH). An increase in collagenase mRNA was detectable 2 h earlier at 100 pM rPTH with a maximal response at least 5-fold greater than that observed for OST- PTP. Levels of mRNA for the structurally similar PTP, rat leucocyte antigen-related molecule, were unaffected by rPTH treatment. Administration of cycloheximide (5-100 microM) abolished the OST-PTP and collagenase responses to PTH. The cAMP analogs, CPT-cAMP (0.01-1mM; 8 h) or Sp-cAMP (0.1 and 0.5 mM) were equal or greater in their effectiveness to enhance both OST-PTP and collagenase mRNA as compared with rPTH. In contrast, phorbol esters, calcium ionophore, bovine PTH (3-34), or human PTHrP (7-34) had no effect on either transcript. Interestingly, 36 h of pretreatment of cells with epidermal growth factor (10 ng/ml), a growth factor known to modulate PTH's actions, resulted in a significant decrease in the abundance of OST-PTP mRNA after rPTH exposure. These studies suggest that regulation of OST-PTP mRNA is a secondary response to PTH stimulation that is dependent on protein synthesis and that may be primarily by activation of the protein kinase A pathway. This specific modulation of a bone receptor PTP may prove to be a critical component in the PTH modulation of osteoblast function.
No More Lemmings, Please – Reflections on the Communal Authority Thesis

A key feature of ISCT is the claim that individuals are required to comply with the norms that are “accepted by a clear majority of the community as standing for an ethical principle” [Donaldson and Dunfee, 1999, The Ties that Bind (Harvard Business School Press, Boson, MA), p. 39], so long as these norms are consistent with hypernorms. I refer to this as the communal authority thesis. Many people see the communal authority thesis as an attractive feature of ISCT, a welcome move away from the abstraction of principle-based ethical theories. I argue in this article, however, that the communal authority thesis is false: we do not have a general moral obligation to comply with the accepted norms in our community. I consider and reject several defenses of the communal authority thesis, including the central arguments put forward by Donaldson and Dunfee. I go on to develop my own position, which accepts that social norms can be important from the moral point of view. However, I argue that social norms are important because they can shape the morally important features of our situation, not because we have a general obligation to comply with these norms as such. I use examples such as gift giving in Japan and the housing crisis to illustrate my position.
The brain wave equation: a model for the EEG

Abstract Both spontaneous and evoked potentials measured on the surface of the head are believed due to postsynaptic potentials in vertically oriented neurons in the cortex. Potential differences between surface locations at any given time are due to the instantaneous difference in synaptic activity between the corresponding vertical regions. Because of the high correlation of activity between regions separated by distances large compared to the radius of influence of single neurons, communication between these locations must be by means of action potentials. In order to quantify the dynamics of interaction of 10 10 cortical neurons, use is made of the concept of a neural mass. The neural mass consists of sufficiently large number of neurons so as to exhibit certain average properties which are independent of its exact inner circuitry. An integral wave equation is derived to describe the spatial-temporal variation of cortical potential. Solutions are obtained indicating that electrical oscillations, which are independent of the location and time history of subcortical input, can persist in the cortex. The nature of these oscillations depends on the relative abundance of excitatory and inhibitory connections between neural masses and on the physiological state of the brain. The latter is partially determined by velocity distribution functions for action potential propagation. A dispersion relation for brain waves is shown to exist for certain ranges of the connection parameters. In some limiting cases, weakly damped waves occur with ω = ck , where c refers to a characteristic velocity for the distribution functions. Preliminary experiments indicate qualitative agreement with this result.
Estimates of infant mortality on the western frontier: the use of genealogical data.

Data from the Mormon Historical Demography Project are evaluated and used to analyze infant mortality in Utah in the mid-nineteenth century. The authors "describe the population under observation evaluate the quality of the genealogical records present infant mortality estimates for birth cohorts in the years 1850-1919 and assess the social-historical and epidemiological conditions that helped shape these patterns." Possible underreporting and potential sources of bias in the genealogical data base are assessed and the pattern of decline in infant mortality and contributing factors are discussed. The findings show that "an incipient decline in infant mortality appeared within both core and periphery areas as early as the cohort of the 1870s though a truly secular decline did not take place until the early 1890s." (EXCERPT)
Correction of image distortion arising from nonuniform sampling

Nonuniformly spaced samples of Fourier transforms of the image are used in holography and in image transmission to reduce the number of samples required to reconstruct an acceptable image. Nonuniform sampling produces image distortion which must be corrected in different ways for noise-free samples than for noisy ones.
Emission modification of CdSe quantum dots by titanium dioxide visible logpile photonic crystal

Air band modes of three-dimensional photonic crystals (3DPCs) have a higher photonic density of states, potentially enabling greater emission enhancement. However, it is challenging to introduce emitters into the “air” region without significantly disturbing the photonic band structure of the PC. Here, we overcome this difficulty by introducing a low refractive index aerogel matrix containing CdSe quantum dots (625 nm peak emission) into a titanium dioxide logpile PC. We observe that the aerogel infiltration indeed preserves the bandstructure. We measure an emission suppression of ∼0.25 times inside and an enhancement of approximately three times outside the bandgap with only one vertical unit cell.
Lattice effects on the dHvA oscillations and magnetic breakdown in quasi-two dimensional organic conductors

Abstract We describe a theoretical approach to investigate the effect of the lattice potential on the dHvA oscillations and magnetic breakdown in quasi-two dimensional organic metals such as α -(BEDT-TTF) 2 KHg(SCN) 4 . We construct a tight binding Hamiltonian based on the extended Huckel approximation to describe these systems which can then be numerically solved to obtain the energy spectrum as a function of magnetic field. Results on the field dependence of the chemical potential and thermodynamic potential are presented.
Characterization of NADPH: Protochlorophyllide oxidoreductase in the y-7 and pc-1 y-7 mutants of Chlamydomonas reinhardtii

Protochlorophyllide (Pchilide) photoconversion, a key step in the biosynthesis of chlorophyll, is catalyzed by the enzyme NADPH: Pchlide oxidoreductase. We have previously shown that the pc-1 mutation of Chlamydomonas reinhardtii causes a defect in photoconversion in vivo. The double mutant pc-1 y-7 failed to photoconvert Pchlide to chlorophyllide, whereas the yellow mutant y-7 showed normal photoconversion (Ford et al. 1981). We have now obtained similar results in vitro, using detergent solubilized membrane preparations. The enzyme activity in y-7 preparations had a pH optimum of 8.5 and had a stringent requirement for both NADPH and Pchlide. We have partially purified the enzyme activity from y-7 by gel filtration. Photoconversion activity eluted with a 320,000 dalton membrane-protein aggregate. Pchlide eluted in two peaks, one of which co-eluted with the enzyme activity peak. Corresponding column fractions from pc-1 y-7 showed similar protein and Pchlide elution profiles, but no enzyme activity. These results suggest that NADPH: Pchlide oxidoreductase is present, but inactive, in the double mutant, and are consistent with the hypothesis that the pc-1 locus codes for the enzyme.
Student Perceptions of the Environment in Guidance and Non‐Guidance Schools

This study attempted to discern differences in student perceptions of the environment in North Dakota Schools with guidance programs and similar schools without guidance programs. The 30 scales of Stern's High School Characteristics Index describing attitudes and impressions of students was used to detect differences. Each scale was analyzed for statistical significance by analysis of variance. Students in guidance schools scored significantly higher on adaptability, aggression, change, counteraction, dominance, scientism, sexuality, and succorance scales. Non-guidance school students scored significantly higher on affiliation, deference, and humanism scales. A description of the two groups using the scale definitions is included in this study.
Investigating Population and Topological Evolution in a Complex Adaptive Supply Network

This paper investigates the dynamics of a complex adaptive supply network (CASN), focusing on understanding stability of the structural evolution of a supply network and supplier population emergence. Supply network evolution data collected from simulated responses of the U.S. automobile industry are used in multivariate statistics and time series analysis to identify patterns of network evolution. This analysis reveals that the type of environment a supply network evolves in appears to be a major factor in determining critical timing of structural changes during the evolution of a CASN. Further, time series analysis of firm population evolution highlights how supply networks evolve due to path dependencies in the CASN system. Information about these two aspects of supply network evolution can prove useful to a decision maker in determining how to respond to supply network changes.
Thermally induced dissociation of ions from electrospray mass spectrometry

The thermally induced dissociation (TID) of inos at near atmospheric pressure, followed by their mass spectraometric analysis, is demonstrated. The TID occurs in a heated metal capillary interface, and should be broadly applicable to any system capable of producing ions at high pressure. The heated capillary provides a reaction vessel, potentially very useful for kinetic and mechanistic studies of ions. The technique has been applied to the fragmentation of large multiply charged ions from an electrospray ionization source. Preliminary results show that stability for multiply protonated petide or protein molecules in inversely related to its charge.
Effects of sample size in classifier design

The effect of finite sample-size on parameter estimates and their subsequent use in a family of functions are discussed. General and parameter-specific expressions for the expected bias and variance of the functions are derived. These expressions are then applied to the Bhattacharyya distance and the analysis of the linear and quadratic classifiers, providing insight into the relationship between the number of features and the number of training samples. Because of the functional form of the expressions, an empirical approach is presented to enable asymptotic performance to be accurately estimated using a very small number of samples. Results were experimentally verified using artificial data in controlled cases and using real, high-dimensional data. >
Synthesis and characterization of iminodiacetate cellulosic sorbent and its application in metal ion extraction

Iminodiacetate cellulosic chelating sorbent, derived from cotton fabric, was synthesized in a two-step reaction sequence. The pH dependence of the metal ion extraction for Cd (II), Co (II), Cu (II), Pb (II), and Ni (II) was studied. Under optimum conditions, the average sorptive capacity of the sorbent was found to be 0.38 mmol metal ion/sorbent. The viability of using this sorbent for recycling, preconcentration of metal ion, and selective metal ion extraction was demonstrated
Production of lantipeptides in Escherichia coli

Lantipeptides are ribosomally synthesized and posttranslationally modified peptides containing thioether cross-links. We describe the preparation of seven different lantipeptides in Escherichia coli and demonstrate that this methodology can be used to incorporate nonproteinogenic amino acids.
Effective detection of a mobile intruder in a partially connected wireless sensor networks

For a wireless sensor network (WSN) to operate successfully in an application of detecting a mobile intruder, the sensor's sensing of the intruder and the communication between the tasking sensor(s) and the base station should be jointly considered for effective intrusion detection. Most related work either treats the two tasks separately or considers both tasks for general-purpose WSN applications in terms of sensing coverage and network connectivity. This work instead investigates the effective intrusion detection problem in a partially connected random WSN from modeling, analysis, and simulation perspectives by integrating the K-sensing and communication tasks. Upper and lower bounds of effective K-sensing intrusion detection probability are mathematically formulated and theoretically derived. Monte-Carlo Simulations are conducted and outcomes are shown to support the theoretical analysis.
EM-based Channel Estimation for Space Time Block Coded MIMO OFDM Systems

We propose a channel estimation technique based on an expectation maximization (EM) algorithm, for space-time block coded (STBC) multi-input multi-output (MIMO) OFDM systems. The channel estimation is done by decomposing the superimposed received signals, into their signal components and estimating the channel parameters of each signal component separately.
Interaction between requesters and a large mechanized retrieval system

Abstract In a large mechanized retrieval system, a certain proportion of the search failures are likely to be directly attributable to inadequate user-system interaction. Request statements may be only distant approximations of actual information requirements. This paper discusses some of the problems of the usersystem interface and suggests methods whereby these problems may be alleviated.
An efficient algorithm to compute the landscape of locally optimal RNA secondary structures with respect to the Nussinov-Jacobson energy model.

We make a novel contribution to the theory of biopolymer folding, by developing an efficient algorithm to compute the number of locally optimal secondary structures of an RNA molecule, with respect to the Nussinov–Jacobson energy model. Additionally, we apply our algorithm to analyze the folding landscape of selenocysteine insertion sequence (SECIS) elements from A. Bock (personal communication), hammerhead ribozymes from Rfam (Griffiths-Jones et al., 2003), and tRNAs from Sprinzl's database (Sprinzl et al., 1998). It had previously been reported that tRNA has lower minimum free energy than random RNA of the same compositional frequency (Clote et al., 2003; Rivas and Eddy, 2000), although the situation is less clear for mRNA (Seffens and Digby, 1999; Workman and Krogh, 1999; Cohen and Skienna, 2002),1 which plays no structural role. Applications of our al- gorithm extend knowledge of the energy landscape differences between naturally occurring and random RNA. Given an RNA molecule a1, ... , an and an inte...
Structural basis of the Escherichi coli outer-membrane permeability

We have studied, using AFM, the structural basis of the outer membrane permeability for the bacterium E. col. The surface of the bacteria is visualized with an unprecedented details. Our AFM images clearly reveal that the outer membrane exhibits protrusions, which correspond to patches of LPS containing hundreds to thousands of LPS molecules. The packing of the nearest neighbor patches is tight, and as such the LPS layer provides an effective permeability barrier for the Gram-negative bacteria. We have also studied the mechanism of their permeability increase upon metal depletion. Our AFM images reveal that LPS molecules are released from the boundaries of some patches during the initial EDTA treatment. Further metal depletion produces a very distinct structure at the outer membrane: appearance of irregularly shaped pits. The pits are likely formed as a result of liberation of LPS patches and lipoproteins, exposing areas of peptidoglacan surface. Our study has proven AFM to be a very useful technique in providing structural basis for the functions of organisms.
A Novel Interaction between Adrenergic Receptors and the α-Subunit of Eukaryotic Initiation Factor 2B

The α-subunit of eukaryotic initiation factor 2B (eIF-2B), a guanine nucleotide exchange protein that functions in regulation of translation, was observed to associate with the carboxyl-terminal cytoplasmic domains of the α2A- and α2B-adrenergic receptors in a yeast two-hybrid screen of a cDNA library prepared from 293 cells. This protein association was confirmed in vitro by affinity chromatography and was shown to be specific for a subset of G protein-coupled receptors, including the α2A-, α2B-, α2C-, and β2-adrenergic receptors, but not the vasopressin (V2) receptor. Association of these proteins in vivo was confirmed by specific co-immunoprecipitation of eIF-2Bα with full-length β2-adrenergic receptors expressed in transfected 293 cells and by fluorescence microscopy showing co-localization of these proteins in intact cells. Remarkably, eIF-2Bα co-localized with receptors exclusively in regions of the plasma membrane that are in contact with the extracellular medium, but failed to associate with membranes making cell-cell contacts. Overexpression of eIF-2Bα in 293 cells caused a small (∼15%) but significant enhancement of β2-adrenergic receptor-mediated activation of adenylyl cyclase, without affecting forskolin or V2receptor-mediated activation. These observations suggest a new role for a previously identified guanine nucleotide exchange protein in membrane biology and cell signaling.
The ferric ion catalyzed decomposition of hydrogen peroxide in perchloric acid solution

Predictions of the “redox” and “complex” schemes for the Fe3+ catalyzed decomposition of H2O2 have been compared with published and new experimental data by numerical integratior of the appropriate complete sets of differential equations. Apparent discrepancies for the redox scheme at high Fe3+/H2O2 ratios are shown to disappear in the complete treatment, and inconsistencies of the complex scheme with both kinetic data and spectroscopic measurements are pointed out.
Reduction of class I expression in a bovine B-lymphoblastoid cell line is locus specific

Abstract A bovine B-lymphoblastoid cell line, BL3.1.2, defective in MHC class I expression was isolated following γ irradiation and immunoselection of a previously mutated cell, BL3.1. Flow microfluorimetry demonstrated that BL3.1.2. cells expressed reduced amount of class I molecules on the cell surface when compared with the parent cells. 2D gel electrophoresis showed that two less class I gene products were synthesized by BL2.1.2 cells than the parent cells. However, no detectable RFLP difference was revealed between this mutant and the parent cell lines as analyzed by Southern blots using bovine class I cDNA and locus-specific oligonucleotide probes, suggesting no major deletions, insertions, or translocations within class I genes. Northern blot analysis, using class I cDNA probes, revealed a marked reduction of class I mRNA in BL3.1.2. cells. RNA unblots, probed with loci-specific oligonucleotides, and blot analysis demonstrated that absence of class I gene transcription was locus specific. This finding indicates there is separate regulation of each class I locus in bovine cells. Furthermore, recombinant IFN-γ upregulated class I gene expression on the BL3.1.2 cells, as indicated by flow cytometry and slot blot analysis. These findings indicate that the locus-specific MHC class I gene was functionally downregulated in its expression. The silent class I gene could be activated by cytokines known to activate the cis-interferon-responsive element for subsequent transcription and translation of the newly synthesized class I RNA. These studies provide evidence that absence of class I gene transcription in BL3.1.2 cells resulted from regulation of a locus-specific gene and suggest that a deficiency in locus-specific trans-acting factor(s) is instrumental in silencing the class I gene.
Possible effects of anthropogenically‐increased CO2 on the dynamics of climate: Implications for ice age cycles

A dynamical model, developed to account for the observed major variations of global ice mass and atmospheric CO2 during the late Cenozoic, is used to provide a quantitative demonstration of the possibility that the anthropogenically-forced increase of atmospheric CO2, if maintained over a long period of time (perhaps by tectonic forcing), could displace the climatic system from an unstable regime of oscillating ice ages into a more stable regime representative of the pre-Pleistocene. This stable regime is characterized by orbitally-forced oscillations that are of much weaker amplitude than prevailed during the Pleistocene.
Leadership Style, Anonymity, and the Discussion of an Ethical Issue in an Electronic Context

A laboratory experiment was conducted with 42 student groups to evaluate the effects of transactional vs. transformational leadership styles and anonymity when groups supported by an Electronic Meeting System (EMS) discussed the ethical issue of copying copyrighted software. A confederate leader displayed either transformational or transactional behaviors. Transformational leaders motivate effort by raising the awareness of followers to make them aspire to higher-order needs and values and by developing them to fulfill their aspirations. Transactional leaders motivate effort by highlighting the contractual exchange involved in a relationship. Participants working with a transformational confederate were more likely to make arguments that challenged the copying of copyrighted software than those working with one who was more transactional. These arguments, in turn, caused groups exposed to such arguments to have greater deviation among its members in intentions to copy the software. Participants working with a transactional confederate were more likely to make arguments in favor of copying copyrighted software. These arguments, in turn, caused groups exposed to such arguments to have a greater mean of intentions to copy the software. Implications for practice and future research on ethics and leadership in the electronic context are discussed.
SLOW MICROWAVE WAVEGUIDE MADE OF NEGATIVE PERMEABILITY METAMATERIALS

The framework for designing a slow light waveguide structure which operates in the GHz and up to THz frequencies is outlined. The design for the structure consists of a dielectric core layer cladded with negative permeability metamaterials. The parameter space for the metamaterial has been identified for the waveguide to stop light and the negative permeability is achieved by split-ring resonator (SRR) metallic elements. A prototype structure operating at 8.5 GHz is proposed. Numerical simulations of electromagnetic waves interacting with SRRs have been performed to extract scattering parameters and a parameter retrieval method has been used to verify the designed window for negative permeability. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2705–2709, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24727
An auditory domain in primate prefrontal cortex.

Although neuroimaging studies confirm the frontal lobe's involvement in language processes and auditory working memory1,2, the cellular and network basis of these functions is unclear. Physiological studies of the frontal lobe in non-human primates have focused on visual working memory and auditory spatial processing in dorsolateral prefrontal cortex (PFC)3,4, although the candidate PFC areas for non-spatial acoustic processing lie in the ventrolateral PFC (areas 12 and 45), which receives afferents from physiologically5,6 and anatomically7,8 defined auditory cortex. We recorded neuronal responses from ventrolateral PFC to auditory cues in awake monkeys under controlled conditions and report that the macaque ventrolateral PFC contains an auditory responsive domain in which neurons show responses to complex sounds, including animal and human vocalizations.
Everybody Else is Doing it, So Why Can't We? Pluralistic Ignorance and Business Ethics Education

In light of the myriad accounting and corporate ethics scandals of the early 21st century, many corporate leaders and management scholars believe that ethics education is an essential component in business school education. Despite a voluminous body of ethics education literature, few studies have found support for the effectiveness of changing an individual’s ethical standards through programmatic ethics training. To address this gap in the ethics education literature the present study examines the influence of an underlying social cognitive error, called pluralistic ignorance. We believe that if pluralistic ignorance is reduced, the result will be more effective business ethics education programs. Eighty undergraduate management students participated in this longitudinal study, and a mixed-model ANOVA revealed that the reduction of pluralistic ignorance (due to an ethics education program designed to reduce pluralistic ignorance) resulted in higher personal ethical standards over the course of a semester, when compared to a class that did not receive a formal ethics education program as part of their course. We discuss the implications of pluralistic ignorance in training business ethics and ethics education.
In vitro polymerization of tau protein monitored by laser light scattering: method and application to the study of FTDP-17 mutants.

Tau polymerization into the filaments that compose neurofibrillary tangles is seminal to the development of many neurodegenerative diseases. It is therefore important to understand the mechanisms involved in this process. However, a consensus method for monitoring tau polymerization in vitro has been lacking. Here we demonstrate that illuminating tau polymerization reactions with laser light and measuring the increased scattering at 90° to the incident beam with a digital camera results in data that closely approximate the mass of tau polymer formation in vitro. The validity of the technique was demonstrated over a range of tau concentrations and through multiple angle scattering measurements. In addition, laser light scattering data closely correlated with quantitative electron microscopy measurements of the mass of tau filaments. Laser light scattering was then used to measure the efficiency with which the mutant tau proteins found in frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTD...
Friendship Intimacy Exchange Buffers the Relation between ADHD Symptoms and Later Social Problems among Children Attending an After-School Care Program

The friendships of children displaying symptoms of attention-deficit/hyperactivity disorder (ADHD) have been understudied, particularly in comparison to the domain of peer rejection. This study tested whether friendship intimacy exchange buffers the prospective relation between ADHD symptoms and social problems 1 year later in a sample of children attending a community-based after-school program. Children (N = 131; 53 % boys; 66 % African American) ranging from 5 to 13 years of age participated in this study. At baseline, children reported on friendship intimacy exchange with their identified best friend, and program staff rated children on ADHD symptoms and social problems. Staff ratings of children’s social problems were collected again 1 year later. Multiple regression analyses indicated that, after controlling for demographic variables and baseline social problems, friendship intimacy exchange significantly moderated the association between ADHD symptoms and social problems at the one-year follow-up. Specifically, the relation between ADHD and social problems was no longer significant for children reporting high levels of friendship intimacy exchange. This moderation was not further qualified by either child age or sex, although boys were more likely than girls to report low rates of friendship intimacy exchange. These findings indicate the importance of friendship intimacy for children displaying ADHD symptoms, who often experience significant peer problems. Friendship quality may be a promising target for prevention and intervention efforts in mitigating some of the long-term social problems associated with ADHD symptomatology, and future research is needed to extend these findings to other domains of friendship quality and clinical samples of children with ADHD.
Significant event simulation

This paper compares a new method of simulation organization, called the significant event method, with an old one, called the clock pulse method, using as examples two automobile traffic models. The significant event method is found to be more efficient than the clock pulse method at low levels of system interaction and less efficient at high levels. A simple mathematical model for the trade-off in the relative running time of the two methods is developed. The model aids in choosing between the two simulation methods for a particular experiment. It is concluded that the significant event method can be of value in the simulation of some systems when computational efficiency is of sufficient importance.
Focus on FOCIS: interleukin 2 treatment associated autoimmunity.

Abstract A patient from the University of Pittsburgh is presented who developed autoimmunity during IL-2 based combination therapy. IL-2 was originally described as a “T cell growth factor” capable of expanding previously activated T cells, enhancing the cytotoxicity of antigen-specific cytotoxic T cells and NK cells. High dose Interleukin 2 (HDIL2) is now FDA-approved for therapy of patients with metastatic melanoma and renal cell carcinoma, based on its ability to induce durable responses in 5–10% of patients. The antitumor effect of HDIL2 is incompletely understood, but it appears that this regimen alters the balance of immigrant T effector cells in relation to T suppressor cells. It promotes a less immunosuppressive tumor microenvironment, inducing tumor regression in a subset of patients that is yet to be defined. The antitumor activity of IL-2, as for other agents that promote durable antitumor activity against melanoma such as interferon alpha and anti-CTLA4 antibody, is frequently associated with development of autoimmunity as observed in this patient. We present studies investigating the mechanisms for the therapeutic benefit of HDIL2 in melanoma.