cssi/SciSciGPT-SciSciNet huggingface dataset:
Image processing algorithms for prostate cancer localization with multispectral magnetic resonance imaging

In this thesis, we develop a series of image processing algorithms to localize prostate cancer with multispectral magnetic resonance (MR) images to guide biopsy, surgery and minimally invasive therapy. Besides, we develop a new method to for evaluation of image classification algorithms considering correlation between neighboring pixels. Prostate cancer is one of the most prevalent cancer types and one of the leading causes of cancer death among men in the United States. High-resolution MRI has shown higher accuracy than trans-rectal ultrasound (TRUS) to ascertain the presence of prostate cancer. In this work, three different types of MR techniques are employed to provide both morphological and functional information about the benign and malignant tissues of the prostate. These are T2-weighted (T2w) MRI, diffusion weighted imaging MRI (DWI) and dynamic contrasted enhanced MRI (DCE MRI). In the first chapter of this thesis, we briefly describe the fundamentals of different MR techniques and the multispectral MR dataset used in our experiment. Then, we focus on two tasks of the prostate cancer localization problem: prostate gland extraction and prostate tumor localization. For each topic, we review the previous studies available in the literature, and present our methods with their advantages. Finally, the new image evaluation method considering correlation between pixels is presented. Our prostate segmentation method is fully unsupervised and extracts the prostate gland from DWI MRI in 3D by fusing the active contour model and shape prior information. For tumor localization, we develop an unsupervised approach which is based on fuzzy Markov random field (fuzzy MRF) model, a new scheme based on relative intensity values which can be combined with supervised segmentation classifiers to mimic the cancer localization procedures performed by human readers and a new feature named location map which incorporates the spatial information of the tumors to remove the need for manual peripheral zone extraction. The proposed image evaluation algorithm is based on receiver operating characteristics (ROC) analysis and it considers the correlation between neighboring pixels. This method could replace the conventional ROC analysis and offers a more accurate evaluation of the test image. Our algorithms are tested on 20 patients' multispectral MR images, and the qualitative as well as quantitative experimental results demonstrate the efficacy of our segmentation methods and show that the proposed segmentation methods outperform the currently available used approaches. The evaluation method has been tested on computer simulated images and shows very promising results. The summary and future work is also described at the end of the thesis.
Cleavage of Cellular and Extracellular Saccharomyces cerevisiae DNA by Bleomycin and Phleomycin

Low-molecular-weight phleomycin (Mr approximately 1500-1600) is considerably less active on a per mol basis than structurally related bleomycin in degrading purified Saccharomyces cerevisiae DNA. Phleomycin also exhibits a substantially higher requirement than bleomycin for ferrous ions. However, phleomycin (0.13 to 3.3 x 10(-6) M) produced 7 to 350 times more breaks than bleomycin in prelabeled intracellular [2-14C]DNA and [6-3H]DNA and is considerably more cytotoxic than bleomycin. Phleomycin and bleomycin produced equivalent numbers of DNA breaks at equivalent, physiologically meaningful levels of survival, indicating that DNA breaks are related to lethal properties of the anticancer glycopeptides. Phleomycin degradation of extracellular DNA was only detectable at greater than or equal to 1.7 x 10(-4) M, approximately two orders of magnitude higher than the concentrations of phleomycin which yielded equivalent fragmentation of intracellular DNA, indicating that phleomycin causes substantially more degradation of intracellular DNA than extracellular DNA. In contrast, bleomycin (greater than or equal to 1.7 x 10(-5) M) degradation of purified DNA is quite extensive and considerably greater than the degradation of DNA in cells incubated with the same or higher concentrations of bleomycin. Neither phleomycin nor bleomycin cleaved extracellular DNA in the absence of ferrous ions, although both chemical analogues cleaved intracellular DNA without adding iron. Therefore, the requirement for metal ion in stimulating DNA degradation by the two structural families of glycopeptidic antibiotics is met by the cell itself.
Physiological consequences of immune response by Drosophila melanogaster (Diptera: Drosophilidae) against the parasitoid Asobara tabida (Hymenoptera: Braconidae)

Abstract Parasites can exert a wide range of negative effects on their hosts. Consequently, hosts that can resist infection should have a selective advantage over nonresistant conspecifics. Yet, host populations remain susceptible to some parasites. Could genetic heterogeneity in the host's ability to resist parasites reflect costs of mounting an immune response? Previous work on Drosophila melanogaster establishes that maintaining the ability to mount an immune response decreases larval competitive ability. Moreover, mounting an immune response decreases fitness. I report on the impact of mounting an immune response on fitness of D. melanogaster survived parasitism by Asobara tabida. I used isofemale lines to determine whether genotype influences the costs of immune response. I examined fitness consequences both to larvae and adults. Survivors of parasitism show no measurable decrease in larval fitness (development time) but have decreased adult fitness (population growth rates), probably because of their smaller size.
Versatile substrate protein recognition mechanism of the eukaryotic chaperonin CCT

Group II chaperonins, found in eukaryotic and archaeal organisms, recognize substrate proteins through diverse mechanisms that involve either hydrophobic- or electrostatic-dominated interactions. This action is distinct from the universal substrate recognition mechanism of group I chaperonins, which bind a wide spectrum of non-native proteins primarily through hydrophobic interactions. We use computational approaches to pinpoint the substrate protein binding sites of the gamma-subunit of the eukaryotic chaperonin CCT and to identify its interactions with the stringent substrate beta-tubulin. Protein-protein docking methods reveal intrinsic binding sites of CCT comprising a helical (HL) region, homologous to the GroEL-binding site, and the helical protrusion (HP) region. We performed molecular dynamics simulations of the solvated CCTgamma apical domain, beta-tubulin peptide-CCTgamma complexes, and isolated beta-tubulin peptides. We find that tubulin binds to CCTgamma through an extensive interface that spans both the HL region and the HP region. HL interactions involve both hydrophobic and electrostatic contacts, while binding to the HP region is stabilized almost exclusively by a salt bridge network. On the basis of additional simulations of a beta-tubulin-CCTgamma complex that involves a reduced interface, centered onto the HP region, we conclude that this salt bridge network is the minimal stabilizing interaction required. Strong conservation of the charged amino acids that participate in the salt bridge network, Arg306 and Glu271, indicates a general mechanism across the nonidentical CCT subunits and group II chaperonins.
Warfarin and the Inhibition of Vitamin K Activity by an Oxide Metabolite

THE isolation and identification of phylloquinone oxide as a metabolite of vitamin K1 in rats given warfarin (3-α-phenyl-β-acetylethyl-4-hydroxycourmarin) led us to investigate the possibility that the oxide is involved in the action of the vitamin or anticoagulant or both1. We knew that phylloquinone oxide had approximately the same activity as vitamin K1 in vitamin K deficient rats but was ineffective in those treated with warfarin2. Evidence that the activity of the oxide was due to its conversion to vitamin K1, a reaction inhibited by warfarin in vivo2, prompted us to investigate the possibility that phylloquinone oxide, because of structural similarity, may be an inhibitor of vitamin K1 and that warfarin exerts its anticoagulant effect by causing accumulation of the oxide.
Calcium uptake in glycerol-extracted rabbit psoas muscle fibers. I. Biochemical properties and conditions for uptake.

Rabbit psoas muscle fibers, extracted in 50% (w/v) glycerol for 20 hours, concentrate up to 300 μmol calcium per gm protein when placed in a suitable electrolyte environment at pH 6.5 containing ATP and 47Ca in the form of a Ca/EGTA metal buffer system. This property is retained at [Ca++] down to 2 × 10−8 M, the lowest studied. The kinetics of Ca pickup are consistent with a mathematical model based on diffusion of Ca as the rate-limiting factor. The pickup is dependent upon ATP and is increased by inclusion of CP or PEP. It is promoted by oxalate, fluoride, phosphate and pyrophosphate, which share the property of forming relatively insoluble calcium salts. Ability to concentrate calcium disappears on prolonged extraction in glycerol and after preincubation with desoxycholate. These properties are similar to those previously described for a granular fraction of muscle homogenates, and it is concluded that both are probably attributable to functional remnants of sarcoplasmic reticulum.
Homotopy continuation methods for computer-aided process design☆

Abstract Homotopy continuation methods have been used by the authors and others to solve difficult chemical engineering flowsheeting and design problems involving the solution of simultaneous nonlinear equations. Such methods can fail when: (1) the homotopy path, which one follows from the solution of a simple problem to the solution of the original (difficult) problem, returns to a second solution of the simple problem; (2) the homotopy path strikes an interior boundary of the domain of definition of the original (vector-valued) function; and (3) the homotopy path goes off to infinity. For the first two modes of failure, the use of an affine homotopy is discussed here as a possible remedy. Failure due to an unbounded homotopy path is the subject of current research.
My evangelical conviction

There are three things that may serve to disrupt the casual habits of intellect operative within a majority of studies that address American religion: (1) poesis must be practiced as a challenge to flat-footed analyses invested in common-sense literacy; (2) there must be an open and honest discussion of how scholars conceive of the characters they study and how they represent those subjects in print or other media; and (3) subtle attention must be paid to issues of discourse, that is, to issues of how people make themselves up even as they are made up by ideas, concepts, and words that have nothing essentially to do with them.
Distress associated with prenatal screening for fetal abnormality

A theoretically-based, multivariate approach was used to identify factors associated with emotional distress for pregnant women undergoing maternal serum alpha fetoprotein (MSAFP or AFP) testing, used to detect abnormalities of the fetal brain and spinal cord. Participants were those who received normal results (N = 87). Study results supported the hypothesis that different factors would predict distress before and after testing. Satisfaction with information about testing predicted lower emotional distress early in the testing process; concerns about the child having other medical conditions and low-dispositional optimism predicted distress later. Study findings indicate that even in women who receive normal test results, AFP testing is associated with a modest degree of emotional disturbance which declines, but does not completely abate, after testing.
Ion transport in inhomogeneous ion exchange membranes

Abstract The effect on current efficiency produced by fluctuations in an ion-exchange membrane's fixed ion concentration (due to ion clustering) is determined by considering transport in several model membranes containing different fixed ion distributions. Electroneutrality is not assumed, so as to include nonlinear effects due to space charge in the clusters. The Nernst—Planck and Poisson equations are solved using perturbation theory, and the case of small fluctuations in fixed charge density is considered in order to obtain analytic solutions to the perturbation equations. Results show that an inhomogeneous distribution of fixed ions gives rise to increased current efficiency when the counterions and co-ions experience in the membrane unequal forces due to the potential produced by the fixed ions. The length scale over which the inhomogeneities occur is important in determining the current efficiency.
Time is traded for intensity in the bat's auditory system

Disparities in time and intensity are the two chief cues animals use for localizing a sound source in space. Echolocating bats belonging to the family Molossidae emit brief, ultrasonic signals for orientation that sweep downward about an octave over the duration of the pulse. Due to acoustic shadowing and the directional properties of the ears, pronounced interaural intensity disparities are created that vary as a function of azimuth. However, due to the small headwidth of these animals, azimuthal changes create small interaural time disparities that are at most 30 microseconds. The experiments in this report are concerned with the binaural processing of time and intensity disparities using brief FM signals that simulate the animal's natural echolocation calls. Binaural neurons receiving excitation from one ear and inhibition from the other (E-I neurons) were recorded from the inferior colliculus of Mexican free-tailed bats. The majority of units sampled were highly sensitive for temporal disparities of 100-300 microseconds, and a few had significant changes in discharge probability when interaural time was changed by 10-20 microseconds. However, all E-I neurons were also sensitive to intensity disparities. With only one exception, all E-I neurons traded time for intensity. On the average, each decibel difference in intensity could be compensated for by advancing or delaying the inhibitory sound by 47 microseconds. The main conclusion is that the auditory system processes interaural disparities by transforming level differences at the two ears into latency differences. Thus the discharge probability of each binaural neuron is determined largely by the arrival times of the discharges from the excitatory and inhibitory ears. In view of the substantial time-intensity trading ratios, the small interaural time disparities produced by azimuthal locations off the midline play no role in shaping the response properties of these neurons. Specific examples of how time-intensity trades can translate into a high spatial selectivity are presented.
The Impact of Heterogeneous Computer Architectures on Computational Physics

Guest editor Barry I. Schneider describes what went into creating this special issue of CiSE magazine, which focuses on high-performance computing and its applications to current subfields of physics and chemistry.
182 PERIPHERAL ARTERIAL INFUSIONS: HISTOLOGIC FINDINGS

Historically, heparinized NS has been used in peripheral arterial lines. The use of dextrose in these lines could potentially increase total daily calories in the critically ill neonate. A study was undertaken to examine the histologic effects of peripheral arterial catheter placement and continuous fluid infusion. Teflon catheters (24g) were placed by surgical cutdown technique into peripheral paw arteries of 20 anesthetized pups. Timed (8h) infusions with the assigned fluid (D5W, D10W) at 2cc/h were used, with control arteries placed to heparin lock or infused with heparinized NS. Arteries were resected, preserved in formalin, then examined histologically (H&E stain) by the pathologist (blinded to specimen fluid group). One or more abnormalities were noted in 73% of the 80 arterial specimens examined. Conclusions: Focal tissue trauma occurs with catheter placement into small peripheral arteries. There was no histologically identifiable difference between control and dextrose infusion groups (p=0.8005). These results suggest that further investigation is needed to determine the safety of arterial dextrose infusion and the long term effects of catheter trauma in peripheral arteries.
Manganese Flux Across the Blood–Brain Barrier

Manganese (Mn) is essential for brain growth and metabolism, but in excess can be a neurotoxicant. The chemical form (species) of Mn influences its kinetics and toxicity. Significant Mn species entering the brain are the Mn(2+) ion and Mn citrate which, along with Mn transferrin, enter the brain by carrier-mediated processes. Although the divalent metal transporter (DMT-1) was suggested to be a candidate for brain Mn uptake, brain Mn influx was not different in Belgrade rats, which do not express functional DMT-1, compared to controls. Brain Mn influx was not sodium dependent or dependent on ATP hydrolysis, but was reduced by mitochondrial energy inhibitors. Mn and Fe do not appear to compete for brain uptake. Brain Mn uptake appears to be mediated by a Ca uptake mechanism, thought to not be a p-type ATPase, but a store-operated calcium channel. Efflux of Mn from the brain was found to be slower than markers used as membrane impermeable reference compounds, suggesting diffusion mediates brain Mn efflux. Owing to carrier-mediated brain Mn influx and diffusion-mediated efflux, slow brain Mn clearance and brain Mn accumulation with repeated excess exposure would be predicted, and have been reported. This may render the brain susceptible to Mn-induced neurotoxicity from excessive Mn exposure.
Prediction of Academic Success in a University Honors Program

The utility of cognitive and biographical variables for the prediction of academic success in a University honors program was investigated. Several variables modestly predicted both college grade point average and final graduation from the honors program. Results were generally supportive of previous research.
Exogenous Insulin Enhances Glucose-Stimulated Insulin Response in Healthy Humans Independent of Changes in Free Fatty Acids

Context: Islet β-cells express both insulin receptors and insulin signaling proteins. Recent studies suggest insulin signaling is physiologically important for glucose sensing. Objective: Preexposure to insulin enhances glucose-stimulated insulin secretion (GSIS) in healthy humans. We evaluated whether the effect of insulin to potentiate GSIS is modulated through regulation of free fatty acids (FFA). Design and Setting: Subjects were studied on three occasions in this single-site study at an academic institution clinical research center. Patients: Subjects included nine healthy volunteers. Interventions: Glucose-induced insulin response was assessed on three occasions after 4 h saline (low insulin/sham) or isoglycemic-hyperinsulinemic (high insulin) clamps with or without intralipid and heparin infusion, using B28 Asp-insulin that could be distinguished from endogenous insulin immunologically. During the last 80 min of all three clamps, additional glucose was administered to stimulate insulin secretion (G...
A matrix representation of the potential second-rank gradient tensor for local modelling

The iron open-sandwich experiments to observe one dimensional development of individual air showers were carried out at Akeno Observatory. One dimensional energy flow, incident energy and production height of shower is estimated using the data of size and age obtained from the above experiment and simple calculation.
Adaptive optics for astronomy

Adaptive Optics (AO) has become a key technology in understanding our Universe. This paper discusses the impact of AO on astronomy and the AO techniques and technology that have been developed to meet the astronomical needs.
Characterization of the Flory-Huggins interaction parameter of polymer thermodynamics

Flory-Huggins theory is the main basis of polymer solution and blend thermodynamics. A key piece of this theory is a parameter quantifying the enthalpic interactions between the components; however, experiments have revealed that this parameter is not composition independent, as originally assumed. This composition dependence has been attributed by some theorists to experimental error; others have tried to explain it based on several competing hypotheses. Here, we use atomistic simulations of isotopic blends based on realistic potentials to study this parameter without making any prior hypotheses. Simulations reveal a composition dependence of this parameter that compares well with experimental data, and serve to verify theoretical relationships between the various forms of this parameter.
A device for inverting the visual field of animals

A device for inverting the visual field of small animals is described. Binocular lenses are mounted in a lightweight, aluminum frame which, in turn, is secured to a surgically attached, dental acrylic skull cap. The construction of the device, and its usefulness when simultaneous electrophysiological recordings are desired, is described by illustrating the details of fabricating such a device for a cat.
Extended storage of streptococcus lactis in phosphate buffer.

Abstract Studies on the Long-Term Storage of Streptococcus Lactis in 0.25m phosphate buffer indicate that a culture can be kept viable and highly active for at least 48 days at 4C. At a high storage temperature (22C), adjuvant materials offer protection to the cells. It is suggested that the production of concentrated liquid cultures for direct vat inoculation is feasible.
Catalyst particle modelling in fixed : bed reactors

Abstract The steady operation of a fixed-bed reactor is analyzed with a detailed computational model, which includes heat and mass transport in the catalyst particles and their boundary layers. Intraparticle transport is described by smoothed-field mass and energy balances, multicomponent flux expressions, and local chemical kinetics. Interphase transport is described by a novel boundary layer treatment, which incorporates an arbitrary j-factor correlation. Plug-flow conservation equations for the bulk fluid states are coupled with the discretized pellet equations, and the resulting differential-algebraic system is integrated downstream by an adaptive implicit algorithm [17,3]. The method is applied to the C7 reforming experiments of Hettinger and coworkers [10] to demonstrate its capability for investigation of multicomponent fixed-bed processes.
Quantifying differential interpretation of public information using financial analysts’ earnings forecasts

Abstract Based on a standard Bayesian learning model, we propose a new measure of differential interpretation of public information, which is applicable to firms with analyst following. We validate our measure in the context of earnings announcements and provide evidence of its greater applicability, relative to a number of previously used proxies, such as the change in dispersion, Kandel and Pearson’s (1995) metric, abnormal volume and the bid–ask spread. We find that the new measure of differential interpretation is related positively to other commonly used proxies, namely trading volume, disclosure informativeness, and the cost of capital, and is related negatively to disclosure readability and management guidance precision. This more precise measure of opinion divergence will enable researchers to pursue studies that were previously difficult to conduct.
Treatment of severe hypertension with intravenous labetalol

The effectiveness of repeated intravenous injections of labetalol in reducing blood pressure (BP) was evaluated in patients with severe hypertension. The subjects were 10 patients who were 29 to 61 yr old and who had diastolic blood pressure (DBP) of 125 mm Hg or higher. Repeated injections titrated from 20 to 80 mg were given at 15-min intervals until there was a reduction in DBP of 30 mm Hg or until 300 mg had been administered. The average reduction of BP ranged from 201 +/- 5/132 +/- 1 to 157 +/- 6/108 +/- 4 mm Hg (mean +/- SEM). Four patients responded with a reduction in DBP of 30 mm Hg or more with total doses of 60 to 220 mg. Of the remaining six who received the full dose, in four there was a 20 to 29 mm Hg reduction in DBP, in one there was a 10 mm Hg fall, and in one there was no reduction. There was a positive correlation between age and response to intravenous labetalol. No severe side effects were encountered. Intravenous labetalol is useful and well tolerated in patients with severe hypertension.
Relationship of Vertical Illuminance to Pedestrian Visibility in Crosswalks

Twenty-six participants evaluated a series of crosswalk lighting designs by visually detecting objects at each crosswalk location while traveling in a moving vehicle. The research was performed on a closed test track under nighttime conditions while the participants were driving an SUV with regular halogen headlamps. The conditions included several vertical illuminance levels (6, 10, 20, and 30 lux), varied luminaire types [highpressure sodium (HPS) and metal halide (MH)], and various target object types (pedestrian and surrogate objects). Only one age group of participants (66 years and older) was used for the study, with equal representation of males and females. The participants were asked to detect objects at each crosswalk location when they were confident an object was present. The results indicated that object detection distances changed on the basis of vertical illuminance level, luminaire type, and object type. Object detection distance for HPS was greatest at 30 vertical lux and for MH at 20 ver...
Construction of Chimeric Phages and Plasmids Containing the Origin of Replication of Bacteriophage Lambda

Segments of the replication control region of bacteriophage lambda (lambda) and lambda mutants defective in replication were attached in vitro to the phi80 phage vector Charon 3 and to the plasmid vector mini Col El (pVH51). The chimeric phages and plasmids have been used to localize the origin of lambda DNA replication and to facilitate a structural analysis of the lambda replicator.
Scalable 3D Bicontinuous Fluid Networks: Polymer Heat Exchangers Toward Artificial Organs

A scalable method for fabricating architected materials well-suited for heat and mass exchange is presented. These materials exhibit unprecedented combinations of small hydraulic diameters (13.0-0.09 mm) and large hydraulic-diameter-to-thickness ratios (5.0-30,100). This process expands the range of material architectures achievable starting from photopolymer waveguide lattices or additive manufacturing.
Chronic lymphocytic leukemia and multiple myeloma in husband and wife.

Abstract Chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) are rare, B-lymphocyte malignancies of unknown etiology. CLL appears to have a strong familial component; 1–8 MM has also been reported in families 8,9 but to a lesser extent. Clinical reports have suggested associations between each of these disorders and prior history of chronic antigenic stimulation from chronic infections, inflammatory or autioimmune diseases; 3,9–16 chronic use of certain drugs; 9 and various occupational exposures 17–25 thought to be related to certain chemicals. Hypotheses as to possible etiologic agents or exposures are usually suggested by clinical clues from in-depth medical histories. We report four suspect exposures shared by a husband and wife who developed the rare, B-cell tumors, CLL and multiple myeloma.
Using Dynamic Assessment to Evaluate the Expressive Syntax of Children who use Augmentative and Alternative Communication

The developmental readiness of four 5-year-old children to produce basic sentences using graphic symbols on an augmentative and alternative communication (AAC) device during a dynamic assessment (DA) task was examined. Additionally, the ability of the DA task to predict performance on a subsequent experimental task was evaluated. A graduated prompting framework was used during DA. Measures included amount of support required to produce the targets, modifiability (change in participant performance) within a DA session, and predictive validity of DA. Participants accurately produced target structures with varying amounts of support. Modifiability within DA sessions was evident for some participants, and partial support was provided for the measures of predictive validity. These initial results indicate that DA may be a viable way to measure young children's developmental readiness to learn how to sequence simple, rule-based messages via aided AAC.
A systematic review of staple-line reinforcement in laparoscopic sleeve gastrectomy.

Background and objectives Laparoscopic sleeve gastrectomy is gaining popularity as a bariatric procedure, with outcomes similar to gastric band and gastric bypass. Staple-line disruption is a significant source of morbidity and death. We aim to evaluate the effect of staple-line reinforcement on the gastric leak rate, morbidity, and mortality rate. Methods A systematic review was performed using title key words "sleeve gastrectomy," and articles were reviewed for description of operative technique and postoperative outcomes including staple-line leak. Rates of leak, bleeding, surgical-site infection, reintervention, readmission, and mortality were analyzed. We calculated pooled event rates and 95% confidence intervals using fixed-effects modeling to determine differences between the reinforcement group (group A) and non-reinforcement group (group B). Results We identified 390 articles, and 30 met the inclusion criteria. Group A had 3293 patients, and group B had 1588 patients. After heterogeneity calculations, 9 variables met the criteria to be analyzed. The leak rate was 3.9% (95% confidence interval, 2.9%-5.5%) in group A and 3.2% (95% confidence interval, 2.8%-4.1%) in group B. The mortality rate was 0.8% (95% confidence interval, 0.4%-1.5%) in group A and 0.7% (95% confidence interval, 0.4%-1.1%) in group B. Our results also showed no statistical difference for any of our other 7 outcome variables. Conclusion Our study shows a lack of statistical difference in leak rate, overall morbidity, or mortality rate in laparoscopic sleeve gastrectomy with or without staple-line reinforcement. Because of study limitations, we propose that prospective trials are needed to determine the effect of staple-line reinforcement on leak rates.
Preparation of Iron Phthalocyanine Catalyzed Carbon Electrodes by Chemical Modification

Abstract A technique for chemically bonding and polymerizing organometallic chelate catalysts on a carbon substrate has been developed, with the objective of improving catalyst activity and stability for the reduction of oxygen in acidic electrolytes. Acetylene black carbon was chemically modified by bonding with polymerized iron tetrachlorophthalocyanine catalyst, followed by heat treatment. An electrode made with this catalyst showed significant improvement in activity and stability as compard with a similar unmodified catalytic electrode.
Projections from the rat pedunculopontine and laterodorsal tegmental nuclei to the anterior thalamus and ventral tegmental area arise from largely separate populations of neurons

Cholinergic and non-cholinergic neurons in the brainstem pedunculopontine (PPT) and laterodorsal tegmental (LDT) nuclei innervate diverse forebrain structures. The cholinergic neurons within these regions send heavy projections to thalamic nuclei and provide modulatory input as well to midbrain dopamine cells in the ventral tegmental area (VTA). Cholinergic PPT/LDT neurons are known to send collateralized projections to thalamic and non-thalamic targets, and previous studies have shown that many of the afferents to the VTA arise from neurons that also project to midline and intralaminar thalamic nuclei. However, whether cholinergic projections to the VTA and anterior thalamus (AT) are similarly collateralized is unknown. Ultrastructural work from our laboratory has demonstrated that cholinergic axon varicosities in these regions differ both morphologically and with respect to the expression and localization of the high-affinity choline transporter. We therefore hypothesized that the cholinergic innervation to these regions is provided by separate sets of PPT/LDT neurons. Dual retrograde tract-tracing from the AT and VTA indicated that only a small percentage of the total afferent population to either region showed evidence of providing collateralized input to the other target. Cholinergic and non-cholinergic cells displayed a similarly low percentage of collateralization. These results are contrasted to a control case in which retrograde labeling from the midline paratenial thalamic nucleus and the VTA resulted in higher percentages of cholinergic and non-cholinergic dual-tracer labeled cells. Our results indicate that functionally distinct limbic target regions receive primarily segregated signaling from PPT/LDT neurons.
Eco-Reps Programs: Conducting Peer Outreach in Residence Halls

Abstract The first eco-reps program was started at Tufts University in Boston in 2000. Since then, nearly 30 additional programs have followed, with additions each year. This paper is the first comprehensive review on how these programs are developed, implemented, and evaluated. We include an overview of the rationale behind eco-reps programs and a discussion of current trends, best practices, and challenges gleaned from a survey of program coordinators. Using as case studies the University of Vermont's established Eco-Reps Program and a program under development at the University of New Hampshire, we outline two examples of peer-to-peer sustainability outreach programs in action.
Interaction of the inhibitory GTP regulatory component with soluble cerebral cortical adenylate cyclase

: Functional interaction of the inhibitory GTP regulatory component (Ni) with the adenylate cyclase catalytic subunit has not previously been demonstrated after detergent solubilization. The present report describes a sodium cholate-solubilized preparation of rat cerebral cortical membrane adenylate cyclase that retains guanine nucleotide-mediated inhibition of activity. Methods of membrane preparation, cholate extraction, and assay conditions were manipulated such that guanosine-5′-(β-γ-imido)triphosphate [Gpp(NH)p] inhibited basal activity 40–60%. The rank order of potency among various GTP analogs was similar in cholate extracts and in membranes: guanosine-5′-0-(3-thiotriphosphate) > Gpp(NH)p > GTP. Inclusion of 0.1 mM EGTA reduced basal activity 70–90% and abolished Gpp(NH)p inhibition of basal activity in both membranes and cholate extracts. Forskolin-stimulated activity was also inhibited by Gpp(NH)p. Treatment of either membranes or cholate extracts with N-ethylmaleimide abolished Gpp(NH)p inhibition. Gel filtration of the cholate extract over a Sepharose 6B column in 0.1% Lubrol PX partially resolved the adenylate cyclase components. However, Gpp(NH)p inhibitin of basal activity (60% of the control) was maintained in select column fractions. Sucrose gradient centrifugation totally resolved the catalytic subunit from both functional Ni and stimulatory GTP regulatory component (Ns) activities. The sedimentation of functional Ni activity was detected by assaying the ability of sucrose gradient fractions to confer Gpp(NH)p inhibition of the resolved catalytic activity. Labeling of gradient or column fractions with pertussis toxin and [32P]NAD revealed that both the 39,000- and 41,000-dalton substrates comigrated with the functional Ni activity. These results demonstrate the feasibility of reconstituting Ni inhibition with resolved catalytic activity directly in solution.
MACROPARTY BEHAVIOR IN CONGRESSIONAL ELECTIONS

This paper examines the relative importance of national forces, local forces, and candidate-related factors on the contribution patterns of national party organizations to congressional candidates. I test two macro-level models: a Party Resources Allocation model and a Candidate Selection model. The results provide evidence for an indirect as opposed to a direct mechanism—party organizations provide financing based on the candidate-related factors, whereas local forces strongly affect candidate selection. As a result, while evidence exists that party actors may be employing national maximization strategies, the strategies used serve only to reemphasize local as opposed to national concerns.
Benefits of Notetaking: Implications for Secondary and Postsecondary Students with Learning Disabilities:

Notetaking is the primary method used by secondary and postsecondary students with learning disabilities (LD) to acquire lecture information. The literature on notetaking was reviewed to obtain an empirical base for designing effective notetaking programming and identifying critical areas for future research. Results include the benefits of recording and reviewing notes as well as identification of listener- and lecturer-controlled variables that influence effective notetaking. Findings are discussed in relation to the learner characteristics of secondary and postsecondary LD students.
Optical detection of cross relaxation in SiC

We report optical detection of cross relaxation (ODCR) for defects in SiC. Many new defects in as-grown and irradiated SiC have been detected by monitoring the effect of their Zeeman energy-conserving spin flips on the triplet bound-exciton luminescence at Ti and at radiation-produced defects. Defects identified by this technique include the nitrogen donor and aluminum acceptor. ODCR may provide a useful new spectroscopic tool for defect study in semiconductors.
The early results of vascular surgery in patients 75 years of age and older: An analysis of 3259 cases

Abstract The population in the United States older than 75 year of age will double by the year 2000. The computerized registry of The Cleveland Vascular Society includes 19,990 vascular procedures, which have been divided into two groups. Group A consists of 16,731 operations performed on patients younger than 75 years of age and group B consists of 3259 procedures performed on patients older than 75 years of age. The overall operative mortality rate in group A was 4.4% (736 of 16,731). In subsets of group B the mortality rates were: age 75 to 79 years, 11.3% (210 of 1862), age 80 to 84 years, 13.4% (125 of 932), age 85 to 89 years, 18.0% (68 of 376), and age 90 to 98 years, 28.1% (25 of 89). In carotid endarterectomy there were no significant differences in the stroke and operative mortality rates when groups A and B were compared. Group A stroke rate was 1.8% (94 of 5220), operative mortality rate was 1.5% (77 of 5220); group B stroke rate was 2.2% (17 of 782) and the mortality rate was 2.3% (18 of 782). For aortic reconstructions group A mortality rate was 7.1% (276 of 3905); group B operative mortality rate was 24.1% (148 of 615) (p
Playing Charades With Your Car – The Potential of Free-form and Contact-based Gestural Interfaces for Human Vehicle Interaction

Modern cars include a host of secondary in-vehicle technology that requires control by the driver. Center-stack touch-screen displays are a popular way to accommodate the proliferation of additional functions through a flexible and scalable interface. However, touch-screens require visual attention for manual selection and provide poor tactile feedback to the driver, which can pose a significant risk while the vehicle is in motion. Inspired by a bimodal control approach, we propose the use of a steering wheel mounted thumb-based gestural interface as part of a larger multi-modal interaction strategy for human vehicle interaction. Following the spirit of Guiard’s (1987) model of bimanual control, a small set of simple gestures for the right hand select appropriate functions within the mode selected by the left hand. A pilot study shows promise of this approach over other, free-form gesturebased methods of interaction.
Transcriptional enhancer related DNA sequences: anomalous 1H NMR NOE crosspeaks.

Abstract A dynamic heterogeneity which correlates with the function of the operator DNA in the lactose operon of E. coli. was previously observed (1) as a local minimum in the thymine imino proton T1 centered at a GTG/C-CAC sequence. Since this triplet occurs frequently in DNA regulatory regions, it was proposed that these sequences may be part of a structural element for specific protein interaction. We examine here three additional biologically significant 17 base pair duplexes containing GTG/CAC triplets: (1) a sequence from the mouse heavy chain immunoglobulin enhancer, (2) a sequence from the critical core of the Simian Virus 40 (SV40) enhancer, and (3) a sequence from pBR322 plasmid used as control for experiments with the SV40 DNA sequences. The 1H NMR resonance assignment for nearly all the nonexchangeable protons for both eukaryotic enhancer duplexes with the exception of the H5'/H5" protons was accomplished to use for structural analysis of these duplexes. The data presented show several NOE's associated with the GTG/CAC triplets which suggest structural variation from uniform B-DNA. In addition, anomalous broad crosspeaks for the fixed thymine methyl to its own H6 proton in combination with the imino proton kinetics associated with these triplets reinforces the original observation of a sequence dependent dynamic variation.
A momentum integral model for prediction of steady operation and flooding in thermosyphons

Abstract An analytical momentum integral model is developed for the prediction of the steady operation of closed two-phase thermosyphons over a wide range of temperatures, pressures and heat inputs. Using a new proposed velocity distribution for the flow of the liquid film, differential equations for mass, momentum, and energy balances have been solved simultaneously to obtain the continuous solution for the thickness of the liquid film, mass flow rate, and heat transfer along the length of the condenser. The interfacial shear due to phase-change at the liquid–vapor interface, as well as acceleration of the condensate film in the momentum balance equation, has been taken into account. The current model uses minimal number of semi-empirical correlations for interfacial shear and heat transfer coefficient and utilizes self-consistent assumptions. The current model is able to accurately predict the essential performance parameters of the system including local and overall mass flow and heat transfer rates through the length of the condenser for a wide range of low to medium heat inputs, up to the flooding limit. Despite the simplicity of the model in comparison to previous studies, the predictions for local mass flow rates and heat fluxes are in excellent agreement with available experimental data.
Supersonic Laminar Viscous Flow Past a Cone at Angle of Attack in Spinning and Coning Motion

Computational results obtained with a parabolic Navier-Stokes marching code are presented for supersonic viscous flow past a pointed cone at angle of attack undergoing a combined spinning and coning motion. The code takes into account the asymmetries in the flowfield resulting from the motion and computes the asymmetric shock shape, crossflow and streamwise shear, heat transfer, crossflow separation and vortex structure. The side force and moment are also computed. Reasonably good agreement is obtained with the side force measurements of Schiff and Tobak. Comparison is also made with the only available numerical inviscid analysis. It is found that the asymmetric pressure loads due lo coning motion are much larger than all other viscous forces due lo spin and coning, making viscous forces negligible in the combined motion.
An alternative computational method for the approximation of random functions

This paper shows that a computational procedure for approximation of random functions can be accomplished using purely linear programming techniques. This contrasts with previous results which use a twostage approach for the computation, one of which requires linear programming techniques. Computational results are given.
A landmark-based transformation approach to concurrency control in group editors

Operational transformation (OT) is a responsive and nonblocking concurrency control method widely-accepted in group editors. Correctness and performance are the basis of usefulness and usability of OT-based group editors. However, the correctness of previous OT algorithms depends on conditions that are very difficult to verify. In this paper we propose a novel landmark-based transformation (LBT) approach, its correctness no longer depending on those conditions and thus easy to prove. In addition, we give an example algorithm that significantly outperforms a state-of-the-art OT algorithm. This work reveals a more practical approach to developing OT algorithms.
Biogeographic contrast of Nucella lapillus responses to Carcinus maenas

Abstract Waterborne cues can initiate a variety of behavioral and morphological defenses. These coevolved recognition systems can be disrupted by abiotic factors, like wave action, or by biological invaders that share no evolutionary history with native communities. In this study, we collected an intertidal whelk ( Nucella lapillus ) from areas in the northeastern USA that have been long-invaded by the predatory crab Carcinus maenas and from areas in Newfoundland, Canada that were uninvaded (or only recently invaded) by the crab. In lab experiments we then juxtaposed the behavioral and morphological responses of Nucella to waterborne cues from invasive Carcinus and the native crab Cancer spp. We found that Nucella from both invaded and uninvaded, wave-protected sites reduced foraging in response to Carcinus , while only whelks collected from invaded, wave-protected sites expressed induced shell thickening or reduced shell growth in response to the invasive crab. In contrast, whelks from wave-exposed sites did not respond to Carcinus behaviorally or morphologically. Although Nucella ' s alteration of foraging and shell weight in response to Cancer spp. resembled responses to Carcinus , whelks did not thicken shell in response to the native crab. Our results indicate that native whelks are capable of recognizing cues from the invasive crab (based on induced behaviors), but the induced morphological responses are absent and perhaps latent in univaded populations. We additionally conclude that the expression of behavioral and morphological defenses may be locally restricted by abiotic conditions such as wave exposure.
Gait patterns during free choice ladder ascents

Abstract Twenty two male subjects each performed five climbing trials of a portable straight ladder. Each subject was instructed to ascend the ladder at a “comfortable” pace using only the rungs for support. For the first, third and fifth trials, the temporal and movement characteristics of the performances were recorded using capacitive touch sensors mounted on each of the rungs and high-speed cinematographical techniques. The results revealed little evidence to suggest a preferred climbing gait. The two most commonly utilized methods of ascent for all trials were the lateral and four-beat lateral gaits. Only 31.8% of the subjects adopted the same gait pattern during each of the three trials. The temporal characteristics of each gait pattern showed a relatively longer time for each segment contact phase than for the corresponding airborne phase. The shortest average period was found for the four-beat diagonal gait followed, in order, by the lateral, diagonal and four beat lateral gaits. Variability measures assumed the same ranking in reverse order with the four-beat diagonal gait producing the most variable period times.