cssi/SciSciGPT-SciSciNet huggingface dataset:
Some More Advanced STEM Problems

This chapter is written for those who wish to understand cutting edge science and engineering topics on an advanced high school level. Einstein’s theory of relativity is presented by explaining how two GPS systems of the inhabitants of two different galaxies would relate to each other. The mathematics used to derive all the expressions of Einstein is on the 8th grade level. The chapter also gives elementary descriptions of modern particle physics and the smallest and recently discovered elementary particles such as quarks and gluons. On the side of the largest dimensions, the chapter presents a detailed description of modern astronomy and the most powerful telescopes searching the universe.Among the advanced engineering projects, we discuss electrical circuits and aspects of the electrical grid that lead to savings in energy consumption. Superconductivity, the absence of electrical resistance, and its possible future applications for the power supply of big cities are also explained.Several sections are included for the STEM lovers who are excited about advanced mathematics, including differential and integral calculus and some of its solutions by modern computer software, particularly by MATHEMATICA. These advanced mathematics tools are then used to show how modern quantum physics performs calculations to find the energy levels and spectra of atoms and molecules and thus explain in principle all of chemistry.
Conformational changes in fibrinogen elicited by its interaction with platelet membrane glycoprotein GPIIb-IIIa

The binding of fibrinogen to membrane glycoprotein GPIIb-IIIa on activated platelets leads to platelet aggregation. This interaction results in conformational changes in fibrinogen as evidenced by the expression of receptor-induced binding sites, RIBS, epitopes which are expressed by the bound but not the free ligand. In the present study, two RIBS epitopes have been localized. One sequence resides at gamma 112-119 and is recognized by mAb 9F9; the second is the RGDF sequence at A alpha 95-98 and is recognized by mAb 155B16. These epitopes are also exposed by adsorption of fibrinogen onto a plastic surface and digestion of the molecule by plasmin. Proteolytic exposure of the epitopes coincides with cleavage of the carboxyl-terminal aspects of the A alpha-chains to form fragment X2. The inaccessibility of the RGDF sequence at A alpha 95-98 in fibrinogen suggests that this sequence does not participate in the initial binding of the molecule to GPIIb-IIIa. The location of these RIBS epitopes suggests a model in which binding of fibrinogen to its receptor alters the conformation of the carboxyl-terminal aspects of the A alpha-chains, exposing the sequences which reside in the coiled-coil connector segments between the D and E domains of the molecule. These sequences may then serve as epitopes and may mediate unique functions of the receptor-bound molecule.
Perspectives on CFD analysis in nuclear reactor regulation

Abstract The U.S. Nuclear Regulatory Commission is tasked with ensuring that the commercial use of nuclear materials in the United States is safe. This includes the review and evaluation of submitted analyses that support the safety justification for specific reactor-system components or scenarios. Typically these analyses involve the use of codes that have a proven history of validation and acceptance for the specific application of interest. The use of computational fluid dynamics (CFD) has not been as widespread in regulatory activities and the experience level with acceptance is more limited. The ever-increasing capacity of computers, along with the growing number of capable analysts, ensures us that CFD applications will continue to grow in usage for nuclear safety analysis. The challenge ahead is to ensure that these tools are properly validated and applied in order to build up the necessary evidence for more common acceptance in regulatory processes. The challenges include a continuation of the development and maintenance of best-practice guidance, development of problem-specific CFD-grade benchmark studies, the application of verification and validation techniques, and the development of practical treatments for uncertainties and scaling. Through these efforts, it is anticipated that CFD methods will continue to gain acceptance for use in nuclear reactor safety applications.
Whispering Gallery Mode Biosensor

None of civilization’s socio-political catastrophes (e.g. world wars) have caused an equivalent destructive effect on the world’s population as biological pandemics [1]. Exponentially growing pathogens are difficult to contain and eliminate unless they can be detected early on. Some years ago, one of us (S.A.) reflected on this problem as a friend was dying from a viral infection. His friend’s diagnosis came too late; real-time methods for testing for the virus were not available. Fast and early detection on site of an outbreak requires biosensors where ideally individual viral particles produce a quantitative signal. A decision was made to direct the MicroParticle PhotoPhysics Lab toward finding a solution. Our approach was to sense bio-particles using the high sensitivity afforded by the perturbation that an adsorbed molecule has on high Q (107) optical resonances of a microparticle [2]. In particular, bio-particle adsorption was sensed from the associated shift in resonance frequency [3, 4]. Through all the eons of evolution, nature has evolved bio-nano-probes that specifically grab onto protein, DNA and foreign invaders through physio-chemical interactions. Following nature, our approach was to use these bio-nano-probes as surface-bound recognition elements and the microparticle to transduce (report) the interaction [5]. We seek to identify the whole virus by tranducing the immobilization that takes place when a coat protein on its surface interacts with a complementary antibody anchored to the microparticle surface. We set a goal to record binding steps of individual virions that can exceed the experimental noise level [6]. Although field effect techniques using nano-fibers have demonstrated single virion sensing in the past [7], reactive Whispering Gallery Mode (WGM) biosensing adds a new dimensions to what can be learned: the measured wavelength shift enables one to identify the virion size and mass. In the process of working on single particle detection we discovered that light confined in a WGM can manipulate a nanoparticle’s motion and substantially enhance the rate at which these particles are sensed. This effect dimensionally reduces the transport process by forming a carousel of particles that “hunt” for anti-bodies where the sensitivity is greatest (WGM Carousel) [8].
Quantum capacitance detector: A pair-breaking radiation detector based on the single Cooper-pair box

We present a proposed design for a pair-breaking photodetector for far-infrared and submillimeter radiation. Antenna-coupled radiation generates quasiparticles in a superconducting absorber, the density of which are measured using a single Cooper-pair box. Readout is performed using an electromagnetic oscillator or a microwave resonator, which is well suited for frequency multiplexing in large arrays. Theoretical limits to detector sensitivity are discussed and modeled, with predicted sensitivities on the order of ${10}^{\ensuremath{-}21}\text{ }\text{W}/\sqrt{\text{Hz}}$. We anticipate that this detector can be used to address key scientific goals in far-infrared and submillimeter astronomy.
Circulatory Assistance With a Permanent Implantable IABP: Initial Human Experience

Purpose The Kantrowitz CardioVADTM (KCV) is an electrically powered, pneumatically driven circulatory assist device which provides diastolic augmentation and systolic unloading to the failing heart. It consists of a 60cc-pumping chamber, a percutaneous access device (PAD), and an external controller. The pumping chamber, is surgically implanted in the descending thoracic aorta with the patient on cardiopulmonary bypass. Its physiologic function is analogous to that of the intra-aortic balloon pump (IABP). Methods Between 1997 and 2000, 5 men (age 59 to 73) with end-stage cardiomyopathy refractory to maximal drug treatment and with documented hemodynamic improvement on an IABP were enrolled in a feasibility study. Results Mean bypass time was 157 minute (range 120 to 196 minute); mean cross-clamp time was 101 minute (range 69 to 144). Patient 1 died intra-operatively. Compared with preoperative values, at 1 month, cardiac index increased (1.7 to 2.6 L/min/m2) and there were significant decreases in creatin...
The S0 and S1 methyl group torsional barriers in 2-methyl-1-naphthol depend upon the orientation of the OH group

Abstract The two OH rotamers of 2-methyl-1-naphthol, syn-2M1HN and anti-2M1HN, have different CH 3 torsional barrier in both their ground and first excited electronic states, as revealed by high-resolution laser studies of their S 1 ←S 0 fluorescence excitation spectra in a molecular beam. A comparison of the measured barriers with the results of ab initio calculations suggests that a primary factor responsible for these differences is a difference in the magnitude of the repulsive steric interactions of the hydrogen and oxygen atoms of the OH group with the eclipsed hydrogen of the CH 3 group.
Pressure dependence of vibrational Raman scattering of narrow-band, 248-nm, laser light by H2, N2, O2, CO2, CH4, C2H6, and C3H8 as high as 97 bar

We have previously investigated methods that image high-pressure processes such as combustion inside automobile cylinders and aircraft engines, or chemical phenomena in supercritical fluids. Here we show that vibrational Raman scattering can simply obtain, quantitatively, densities of some combustion-relevant molecules. We use narrow-band KrF excimer-laser light. Measurements for H2, N2, O2, CO2, and CH4 are in the pressure range from 1 to 60 bar, whereas those for C2H6 and C3H8 are up to their respective vapor pressures. All these species are at ambient temperature. Additional measurements are described for CO2 up to 96.8 bar and 318 K, where CO2 is a supercritical fluid. The O2 measurements are complicated by a photochemical formation of O3; those in supercritical CO2 by drastic bending of the laser beam within this medium. We show that, for each gas, the Raman signal is directly proportional to gas density, thereby making quantitative analysis particularly convenient. For each species, we present an estimate of its Raman cross-section relative to that of N2. However we recommend that future diagnostics users calibrate their own systems for relative species sensitivity.
Persistence of Dispersal-limited Species in Structured Dynamic Landscapes

Dynamic landscape models have generally assumed random distributions of habitat although real landscapes show spatial organization at many scales. To explore the role of spatial structure in determining the frequency of dispersal-limited forest species, we used a cellular landscape model divided into two zones. Zones were distributed in a random, clustered, or regular spatial pattern. Within each zone habitat cells were randomly destroyed and regenerated, and habitat density and turnover rate were systematically varied. A hypothetical habitat-limited species dispersed between adjacent habitat cells. All trials showed a reduced species frequency relative to a static landscape. Reduction was greater at low habitat density (P = 0.30) than at high density (0.90) suggesting the importance of habitat connectivity in controlling species frequency. The greatest reduction occurred when habitat was concentrated in a small, regularly distributed zone at low habitat density reflecting the enforced isolation of individual habitat cells. Very little reduction was observed when habitat cells were packed into a small clustered zone, a situation promoting connectivity between cells. Moderate–severe frequency reduction occurred when habitat turnover was concentrated in a clustered zone at high habitat density, but little was observed when turnover was widely distributed in a regular or random pattern. These results can be interpreted in terms of a source-sink function in which spatial pattern controlled the degree of contact between landscape zones and determined opportunities for dispersal between habitat cells. We conclude that clustering of forest habitat has the potential to maintain herb species frequency in sparsely forested landscapes. Conversely, clustering of forest disturbance in heavily forested regions, or regular distribution of forest stands (as often occurs in agricultural regions) creates areas which are difficult to colonize, and should be avoided.
Optical imaging applied to microelectronic chip-to-chip interconnections.

An imaging system is proposed as an alternative to metallized connections between integrated circuits. Power requirements for metallized interconnects and electrooptic links are compared. A holographic optical element is considered as the imaging device. Several experimental systems have been constructed which have visible LEDs as the transmitters and PIN photodiodes as the receivers. Signals are evaluated at different source–detector separations. Multiple exposure holograms are used as a means of optical fan out allowing one source to simultaneously address several receiver locations. Limitations of this technique are also discussed.
Tunable holographic interferometer using photorefractive crystal

We present a holographic interferometer using a photorefractive crystal SBN:60. A point source is recorded inside the crystal via two wave-mixing. By displacing the crystal laterally or radially a tunable Young''s interferometer or a tunable Michelson interferometer is constructed respectively. An advantage of this device is the elimination of errors due to hologram developing and repositioning processes. The interferometer is capable of producing sinusoidal gratings and zone plates. 1.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Single Molecule Mechano-Memory

Understanding the spatial distribution of individual adhesion bonds and the tension exerted on them is crucial for understanding whole cell adhesion behavior. Here, we introduce a new class of molecular force sensors to record cellular adhesion events at the single-molecule level. A DNA structure was designed that responds to mechanical perturbation above certain threshold tension and maintains a memory of that perturbation. We name this feature "single-molecule mechano-memory" (smMM). The smMM sensor undergoes conformational changes under tension and is kinetically trapped under a new conformation. Single-molecule force spectroscopy and fluorescence spectroscopy were performed to characterize the activation force as well as memory life time. We show that in the absence of mechanical perturbation the smMM sensor is well folded and stable. In the presence of tension above ∼35 pN, the sensor is converted to the unfolded "memory" state in which it remains kinetically trapped for an average of 25 seconds. Both activation force and life time of the sensor can be tuned by its DNA sequence. As a proof of concept for this class of sensors, smMM sensors were coated on a surface where cell adhesion takes place. Individual adhesion events are detected using fluorescently-labeled oligonucleotide probes to mark unfolded sensors.
Uptake Of S100A1 And Augmentation Of Cav1 Channel Current And Action Potential Duration In Sympathetic Ganglion Neurons

S100A1, a ∼20 kD dimeric Ca2+-binding protein of the EF-hand type, is highly expressed in cardiomyocytes and is considered an important regulator of heart function. During ischemia, cardiomyocytes release S100A1 to the extracellular space. Although the effects of extracellular S100A1 have been documented in cardiomyocytes, it is unclear whether S100A1 exerts modulatory effects on other tissues in close proximity with cardiac cells. Neurons from the cervical ganglion chain extend postgaglionic axons that innervate the heart. Therefore, we sought to investigate the effects of exogenous S100A1 on Ca2+ signals and electrical properties of principal sympathetic ganglion neurons (SGNs) from the superior cervical ganglion. Immunostaining and western blot analysis did not detected any endogenous S100A1 in SGNs from normal mice. Cultured adult SGNs took up fluorescent S100A1 when it was present in the extracellular media. Inside the cell exogenous fluorescent S100A1 localized primarily in a punctuate pattern throughout the cytoplasm and axoplasm, but was excluded from the nuclei. Time lapse imaging and FRAP experiments reveal axonal transport of S100A1 puncta, presumably endosomes. In compartmentalized (Campenot) SGN cultures, axonal projections were capable of uptake and transport of S100A1 towards the neuronal somas. Exogenous S100A1 enhanced Cav1 channel currents, increased the amplitude of action potential-evoked Ca2+ transients and prolonged the action potentials. Our results, showing enhanced somatic Ca2+ entry, larger cytosolic Ca2+ transients, and prolongation of action potential duration, suggest the hypothesis that S100A1 released from heart muscle cells may be taken up by sympathetic neurons, leading to an increase of sympathetic output to the heart. Supported by NIH, Grants R01-N5042839, R01-AR055099.
Analytical Temperature Distribution in a Multi-Layer Tissue Structure in the Presence of a Tumor

Analytical study of bioheat transfer is of significant importance for a number of biomedical applications including cryopreservation of tissue and thermal therapy for cancer. A sound fundamental understanding of thermal behavior of tissue in response to an externally applied stimulus helps design effective therapies and protocols. This paper derives an analytical solution in a multi-layer two-dimensional structure with arbitrary, space-dependent heat generation occurring in each layer. This geometry effectively models multiple layers of skin, with heat generation due to cancerous cells in the basal layer. The Pennes bioheat transfer equation is solved for the multi-layer analytically, wherein the temperature in each layer is explicitly a function of space and the thermo-physical properties of the layer. The resulting analytical temperature profile agrees well with finite-element simulations and is also in good agreement with a previously published experimental study. Results derived in this work illustrate the effect of the presence of cancerous cells on the thermal profile of the skin. Further, the model helps to understand the effect of external cooling and heating stimuli.Copyright © 2013 by ASME
Pharmacokinetic alterations after severe head injury. Clinical relevance.

Pharmacological therapy, present and future, will undoubtedly continue to play a large role within the overall management of patients with severe head injury. Nevertheless, limited clinical data are available to evaluate the effect of severe head injury on pharmacokinetics. The disruption of the blood-brain barrier secondary to trauma and/or subsequent hyperosmolar therapy can be expected to result in higher than expected brain drug concentrations. Aggressive dietary protein supplementation may result in increased oxidative drug metabolism. These effects may counterbalance inhibitory influences on drug metabolism secondary to cytokine release during the acute phase response. Alterations in protein binding can also be anticipated with the hypoalbuminaemia and increases in alpha 1-acid glycoprotein typically observed in these patients. Based on studies in other patient populations, moderate hypothermia, a treatment strategy in patients with head injury, can decrease drug metabolism. The pharmacokinetics of the following drugs in patients with severe head injury have been studied: phenytoin, pentobarbital (pentobarbitone), thiopental (thiopentone), tirilazad, and the agents used as marker substrates, antipyrine, lorazepam and indocynanine green (ICG). Several studies have documented increase in metabolism over time with phenytoin, pentobarbital, thiopental, antipyrine and lorazepam. Increases in tirilazad clearance were also observed but attributed to concurrent phenytoin therapy. No changes in the pharmacokinetics of ICG were apparent following head injury. With the frequent use of potent inhibitors of drug metabolism (e.g., cimetidine, ciprofloxacin) the potential for drug interaction is high in patients with severe head injury. Additional pharmacokinetic investigations are recommended to optimise pharmacological outcomes in patients with severe head injury.
The differential effects of 12-O-tetradecanoylphorbol-13-acetate on the gap junctions and connexins of the developing mammalian lens.

Epithelial cells in primary ovine lens cultures express the gap junction proteins connexin43 (Cx43) and connexin49 (Cx49; a.k.a. MP70), a homologue of mouse connexin50. In contrast, lens cultures of differentiated, fiber-like cells (termed lentoid cells) express Cx49 and connexin46 (Cx46), but not Cx43. To investigate the regulation of lens cell gap junctions by protein kinase C (PKC), differentiating lens cultures were treated with the PKC activator 12-O-tetradecanoylphorbol-13-acetate (beta-TPA). Within 10 min, beta-TPA significantly inhibited the transfer of Lucifer Yellow dye between epithelial, but not lentoid, cells. This inhibition was correlated with the phosphorylation of Cx43 and was followed by the gradual disappearance of Cx43 from cell interfaces. The protein kinase inhibitor staurosporine prevented Cx43 phosphorylation and the loss of Cx43 from intercellular junctions. Following treatment of cultures with beta-TPA for 2-6 hr, Cx49 disappeared from epithelial cell interfaces, and by 24 hr of beta-TPA treatment, levels of Cx49 detected on immunoblots of purified epithelial membrane fractions had also diminished significantly. The beta-TPA-induced loss of Cx49 both from regions of epithelial cell contact and from isolated membranes was correlated with the disappearance of Cx49 mRNA. In contrast to the epithelial connexins, the lentoid connexins Cx49 and Cx46 were unaffected by even extended beta-TPA treatment. In spite of lentoid dye transfer being refractory to beta-TPA, significant levels of PKC-alpha (a beta-TPA-sensitive isoform) were detected in the lentoid cell. The response of lens gap junctions to beta-TPA depends upon the stage of differentiation and the complement of connexins expressed. The contrasting effects of beta-TPA on Cx43 and Cx49 in lens epithelial cells indicate a fundamental difference in the regulation of these connexin proteins in the developing mammalian lens.
Niche market strategy for a mature marketplace

Purpose – To examine how companies in the maturity stage of the product life cycle can implement and maintain a successful niche market strategy to increase competitiveness in the face of new competition, with particular reference to the global textile industry.Design/methodology/approach – Responsible executives in eight firms in the textile and apparel/clothing sector in the USA were interviewed face‐to‐face or by telephone, or completed an online questionnaire. The sample contains leaders in the industry.Findings – Research results suggest that niche marketing is an effective strategy for countering price competition in a mature industry and can use a niche market strategy. They identify key success factors, the most important factor of which was found to be a thorough understanding of the targeted consumers. It is concluded that the marketing mix plays a more important part than is generally suggested in the literature, by communicating non‐price product attributes to the niche market.Research limitat...
Human performance at the roof of North America

The effects of altitude on human performance and cognition were evaluated in a field study performed on Mt. McKinley in Alaska. Climbers performed a series of perceptual, cognitive, and motor tasks before, during, and after climbing the West Buttress route on Mt. McKinley. Relative to a matched control group who performed the tasks at sea-level the climbers showed deficits in learning and retention on perceptual and memory tasks. Furthermore, climbers performed more slowly on most of the tasks suggesting long term deficits which may be attributed to repeated forays to high altitudes.
Resolutions which split off of the bar construction

Abstract Resolutions which split off of the bar construction are quite common, but explicit formulae expressing these splittings are not often encountered. Given explicit splitting data, perturbations of resolutions can be computed and the perturbed resolutions can be used tomake complete effective calculations where previously only partial or indirect results were obtainable. This paper gives a foundation for the perturbation method in homological algebra by providing a symbolic encoding of binomial coefficient functions which is useful in deriving formulae for an infinite class of resolutions. Formulae for perturbations of those resolutions are then derived. Applications to certain infinite families of groups and monoids are given. The research for this theory as well as the calculation of closed formulae within the theory was aided by new methods in symbolic computation using the Axiom (formerly called Scratchpad) system.
On screening samples in the laboratory and factors in factorial investigations

Procedures such as group testing and fractional replication can greatly reduce the workload. The former is especially efficient when the presence of a characteristic in samples is low. Fractional replication can greatly reduce the amount of experimentation when some of the parameters associated with a factorial are nonexistent or negligible. Supersaturated fractional replication can be used to efficiently screen factors when it is suspected that they may not affect a process but it is desired to check this suspicion. There are many types of grouping and pooling material in an investigation. Some of these are discussed as are the interrelationships among the above procedures.
The association of sugar-sweetened beverage intake during infancy with sugar-sweetened beverage intake at 6 years of age.

OBJECTIVES: To examine whether sugar-sweetened beverage (SSB) intake during infancy predicts SSB intake at 6 years of age. METHODS: A longitudinal cohort analysis of 1333 US children was conducted by using data from the 2005–2007 Infant Feeding Practices Study II and the 2012 Follow-Up Study at 6 years of age. The exposure variables were maternal-reported SSB intakes during infancy. The outcome variable was maternal-reported SSB intake at age 6 years. Multivariable logistic regression analyses were used to calculate adjusted odds ratios (aOR) for associations of SSB intake during infancy with consuming SSBs ≥1 time/day at 6 years old after controlling for baseline child’s and parent’s characteristics. RESULTS: Based on maternal recall, approximately one-fifth of children consumed SSBs at least 1 time/day at age 6 years. Adjusted odds of consuming SSBs at age 6 years ≥1 time/day was significantly associated with any SSB intake during infancy (aOR, 2.22 vs none), age at SSB introduction (aOR, 2.33 for age ≥6 months and 2.01 for age CONCLUSIONS: SSB intake during infancy significantly increased the likelihood of consuming SSBs ≥1 time/day at 6 years of age. Our findings suggest that infancy may be an important time for mothers to establish healthy beverage practices for their children and these findings can be used to inform intervention efforts to reduce SSB intake among children.
Association between new york and shanghai markets: evidence from the stock price indices

Abstract This paper examines the time series characteristics of stock price indices for New York and Shanghai during the period of 1991 to 2009. Specifically, we calculate the rate of return and the volatility of return for two markets and estimate the serial correlation and co-movement of the two markets. We find that the average rate of return in Shanghai is much higher than that in New York while Shanghai stock prices are more volatile than New York stock prices. Further, we find that Shanghai stock prices are positively serially correlated while New York stock prices are negatively serially correlated in terms of auto regression of the rate of return. In the multivariate regressions, we find that there is little evidence to show that either the rate of return in Shanghai would affect the rate of return in New York or the rate of return in New York would affect the rate of return in Shanghai. It suggests that the two markets are not integrated. Last, we studied and made conclusion concerning the volati...
MiR-30 family and EMT in human fetal pancreatic islets.

Small, noncoding ribonucleotides called micro RNAs (miRNAs) have recently emerged as important regulators of cell function. MiRNAs regulate gene expression mainly by binding to the 3' UTR of mRNAs and thereby inhibit the translation of target mRNAs. The abundance of many miRNAs is altered under physiological and pathophysiological conditions, such as cancer and neurodegeneration. Recent data suggest that miRNAs also have an important role in regulation of insulin gene transcription, insulin secretion, and pancreatic islet cell function. An interesting study by Joglekar et al. published in this issue of ISLETS suggests that the miR-30 family of miRNAs may control the epithelial-to-mesenchymal transition of primary cultures of human pancreatic epithelial cells by negatively regulating the translation of mesenchymal gene transcripts such as vimentin. These findings are in agreement with previous data that suggest an important role for one of the miR-30 family members (miR-30d) in insulin gene expression in p...
The role of secondary motor and language cortices in morbidity and mortality: a retrospective functional MRI study of surgical planning for patients with intracranial tumors.

Object Functional MRI (fMRI) is commonly used by neurosurgeons preoperatively to identify brain regions associated with essential behaviors, such as language and motor abilities. In this study the authors investigated the relationship between patient morbidity and mortality and the distance from the tumor border area to functional activations in secondary motor and language cortices. Methods Patients with primary or metastatic brain tumors who underwent preoperative fMRI motor and language mapping were selected from a large database of patients with tumors. The lesion-to-activation distance (LAD) was measured in each patient relative to the supplementary motor area (SMA) for motor tasks and the presupplementary motor area (pSMA) for language tasks. The association between LAD and the incidence of deficits was investigated using the Fisher exact tests of significance. The impact of other variables, including age, handedness, sex, and tumor grade, was also investigated. In a subset of patients, logistic reg...
Pertechnetate (TcO4−) reduction by reactive ferrous iron forms in naturally anoxic, redox transition zone sediments from the Hanford Site, USA

Abstract Technetium is an important environmental contaminant introduced by the processing and disposal of irradiated nuclear fuel and atmospheric nuclear tests. Under oxic conditions technetium is soluble and exists as pertechnatate anion (TcO4−), while under anoxic conditions Tc is usually insoluble and exists as precipitated Tc(IV). Here we investigated abiotic Tc(VII) reduction in mineralogically heterogeneous, Fe(II)-containing sediments. The sediments were collected from a 55 m borehole that sampled a semi-confined aquifer at the Hanford Site, USA that contained a dramatic redox transition zone. One oxic facies (18.0–18.3 m) and five anoxic facies (18.3–18.6 m, 30.8–31.1 m, 39.0–39.3 m, 47.2–47.5 m and 51.5–51.8 m) were selected for this study. Chemical extractions, X-ray diffraction, electron microscopy, and Mossbauer spectroscopy were applied to characterize the Fe(II) mineral suite that included Fe(II)-phyllosilicates, pyrite, magnetite and siderite. The Fe(II) mineral phase distribution differed between the sediments. Sediment suspensions were adjusted to the same 0.5 M HCl extractable Fe(II) concentration (0.6 mM) for Tc(VII) reduction experiments. Total aqueous Fe was below the Feaq detection limit (
BaSO4-Loaded Agarose

Abstract Rationale and Objectives Phantom studies are an important part of the evaluation of imaging techniques; however, presently available phantom construction materials are not adequate for studies involving both magnetic resonance (MR) imaging and computed tomography (CT). The purpose of this study was to design a phantom construction material useful for multimodality imaging experiments. Materials and Methods Iodinated contrast agent or BaSO4 was added during the formation of agarose gels. Both CT and MR imaging were performed, and T1 and T2 values and CT numbers (in Hounsfield units) were obtained for multiple combinations of contrast material and agarose. Results The T2 values of agarose gels span the range of those values found in biologic tissues. Phantoms containing iodinated contrast agent were not stable; contrast agent diffused across concentration gradients. BaSO4–loaded agarose phantoms were stable, however, and varying barium concentrations produced phantoms that spanned the range of CT numbers found in biologic tissues. Addition of BaSO4 did not substantially alter T1 or T2 values of agarose gels. Agarose concentration had only a small effect on the CT numbers of BaSO4 suspensions. Conclusion BaSO4-loaded agarose is an effective material for construction of multimodality imaging phantoms. It provides adequate signal intensity for MR imaging and attenuation for CT, with independently variable contrast in both modalities.
Modeling coupled lines in 65 nm CMOS for millimeter-wave applications

An analysis of the behavior of coupled lines in the 100-200 GHz frequency range is presented. Characterization of lumped and electromagnetic elements are included as a preliminary work to predict the behavior of the line in a Rotary Traveling Wave Oscillator (RTWO) integrated circuit. Using Sonnet and Agilent ADS, the simulated behavior of a coupled transmission line implemented in 65 nanometer CMOS is presented as well as the method used for modeling the lines.
Toward Improved Conductivity of Sulfonated Aromatic Proton Exchange Membranes at Low Relative Humidity

Three sulfonated aromatic polymers with different sequence lengths were studied in order to better understand the relationship between molecular structure, morphology, and properties of proton exchange membranes as a function of relative humidity. A random copolymer with a statistical distribution of sulfonic acid groups had very small domain sizes, whereas an alternating polymer with sulfonic acid groups spaced evenly along the polymer chain was found to have larger, but quite isolated, domains. The multiblock copolymer studied herein showed highly phase-separated hydrophilic and hydrophobic domains, with good long-range connectivity. Scanning force microscopy as a function of relative humidity was used to observe water absorption and swelling of the hydrophilic domains in each of the three membranes. The conductivity, water sorption kinetics, and fuel cell performance, especially at low relative humidity, were found to be highly dependent upon the morphology. The multiblock copolymer outperformed both t...
AX.25 [data link layer protocol for packet radio networks]

For packet radio networks, the AX.25 data link layer protocol is most often used. However, TCP/IP (Transport Control Protocol/Internet Protocol) is also popular. The AX.25 protocol is a variant of the international X.25 protocol applied to wireless communication and packet radio. Most networks are composed of copper or fiber optic cable and provide reliable communication between hosts. The wireless medium is vastly different. It is less reliable and suffers from phenomena that are not present in conventional wired networks. For example, in a cable network all hosts on a network can hear each other. This makes "carrier sense" protocols such as Ethernet easy to implement. Before any host seizes the network, it first listens to help avoid collisions. Wireless networks also support carrier sense. However, hosts on the network cannot always hear each other for numerous reasons. Buildings and the local terrain are two important factors that determine the ability to receive information. We concentrate on the analysis of AX.25 packet radio networks operating in the 144-148 MHz band. Understanding and studying a network is a com analyzers, sometimes called "sniffers," are available to aid the packet user in understanding how a network operates. XNET, a network analyzer developed specifically to examine AX.25 networks, is described.
Dropped Gallstone as a Nidus of Intra-abdominal Abscess Complicated by Empyema

We describe a patient who developed an intra-abdominal abscess and empyema from a dropped gallstone at the time of laparoscopic cholecystectomy 1.5 years ago. As minimally invasive surgeries become conventional, clinicians should be aware of this increasingly common complication.
Nonlinear baseband filters for optical pattern recognition

A nonlinear filter based image correlator is investigated. The linear filter is expressed as the real part of the conventional matched filter. This baseband function contains the amplitude and phase of the Fourier transform of the reference signal. The real baseband filter function is then applied to a nonlinear device to produce the nonlinear filter function. Analytical expressions for the nonlinear filter are provided. The effects of the nonlinear transfer characteristics on the correlation signals at the output plane are investigated. The correlation signals are determined in terms of the nonlinear characteristics used to transform the filter. We show that the nonlinear filter results is a sum of infinite harmonic terms. Each harmonic term is envelope modulated due to the nonlinear characteristics of the device, and phase modulated by m times the phase modulation of the linear filter function.
Positive and negative nucleation catalysis in crystallization

Abstract The time of exposure of silver iodide to white light affects its ice nucleating abilities because the number of hydrophilic sites generated increases with time. For a not too large number of such sites the surface free energy substrate-nucleus is decreased and, as a consequence, the rate of nucleation increased. A longer time of exposure generates a large number of sites; these cause distortion in the interface, increasing the surface free energy substrate-nucleus and decreasing the rate of nucleation. Substitutional nonionic impurities with a radius larger than that of the main component (also nonionic) might have a negative effect on the rate of homogeneous nucleation. This effect is caused by the strain energy generated in the lattice of the nucleus. In the opposite case they may have a positive effect. Ionic impurities in an ionic system have similar effects if the valence of the impurity is equal to that of the main component. A discussion concerning the effect of ionic impurities with a higher valence than the main component is also included. The strain energy is calculated on the basis of a continuum model. Conditions in which nucleation is suppressed are established.
Levels of Processing and Memory in Mentally Retarded and Nonretarded Persons.

Abstract Individual differences in memory were examined from the levels of processing perspective. Mentally retarded persons were expected to be more superficial processors. The recall of nonretarded and two IQ levels of retarded young adults was compared following the presentation of pictorial stimuli with either a shallow processing, deep processing, or control orienting task. Shallow processing was induced by directing subjects to name the colors of the pictures. In the deep processing condition, subjects were told to say what the pictured object was used for. In the control condition, they were directed to look at the pictures. The stimuli were presented as an incidental learning task. Encoding condition was a between-subjects variable. Nonretarded subjects remembered more overall than did the two retarded groups, which did not differ. At each intelligence level, more stimuli were remembered in the deep processing condition than in the shallow condition. There was no interaction of intelligence level with encoding condition. The hypothesis that retarded persons process at a more superficial level was not supported. A “spread of encoding” deficit in retarded persons is favored to explain the recall differences obtained in this experiment.
Velocity, occlusion, and sex of subjects in coincidence of anticipation.

The purpose of this study was to assess effects of velocity, occlusion distance, and sex on coincidence of anticipation. The Bassin anticipation timer was used to test 25 men and 25 women when velocity was .69 m/sec. and 1.38 m/sec. or “slow” and “fast”, and occlusion distances of zero, 1.06 m and 2.12 m were “zero,” “small,” and “large” on a 4.25-m length of track. There were six test conditions. Analysis showed that increased occlusion distances produced increased absolute, constant, and variable error scores. A significant interaction of velocity and occlusion appeared for all error measures. With an increase in occlusion distance at the slow velocity constant error increased in the positive direction or early response while at the fast velocity a similar increase in constant errors was seen but in the negative direction or late response. Under zero occlusion the expectation that performance at the fast velocity would be more accurate and show less variability than at the slow velocity was not supporte...
Reflections on a Pair of Theorems by Budan and Fourier

Isolation of the real roots of a polynomial equation is the process of finding real, disjoint intervals such that each contains exactly one real root and every real root is contained in some interval. This process is quite important because, as J. B. J. Fourier pointed out, it constitutes the first step toward the solution of general equations of degree greater than four, the second step being the approximation of roots to any desired degree of accuracy. In the beginning of the 19th century F. D. Budan and J. B. J. Fourier presented two different (but equivalent) theorems which enable us to determine the maximum possible number of real roots that an equation has within a given interval. Budan's theorem appeared in 1807 in the memoir "Nouvelle methode pour la resolution des equations numeriques" [10, p. 219], whereas Fourier's theorem was first published in 1820 in "Le Bulletin des sciences par la Societe Philomatique de Paris," pp. 156, 181 [10, p. 223]. Due to the importance of these two theorems, there was a great controversy regarding priority rights. In his book (1859) "Biographies of distinguished scientific men," p. 383, F. Arago informs us that Fourier "deemed it necessary to have recourse to the certificates of early students of the Polytechnic School or Professors of the University" in order to prove that he had taught his theorem in 1796, 1797 and 1803 [10]. Based on Fourier's proposition, C. Sturm presented in 1829 an improved theorem whose application yields the exact number of real roots which a polynomial equation without multiple zeros has within a real interval; thus he solved the real root isolation problem. Since 1830 Sturm's method has been the only one widely known and used, and consequently Budan's theorem was pushed into oblivion. To our knowledge, Budan's theorem can be found only in [16] and [61 whereas Fourier's proposition appears in almost all texts on the theory of equations. We feel that Budan's theorem merits special attention because it constitutes the basis of Vincent's forgotten theorem of 1836 which, in turn, is the foundation of our method for the isolation of the real roots of an equation [1], a method which far surpasses Sturm's in efficiency [2], [3]. In the discussion which follows we present separately, and without proofs, the classical theorems by Fourier and Budan and we indicate how they lead to the corresponding real root isolation methods. Some empirical results are also presented for comparison.
Recursive predictor design for state and output feedback controllers for linear time delay systems

This paper presents a recursive method to design state and output feedback controllers for MIMO, block-feedforward linear systems with delays in the inputs, outputs, and interconnections between the blocks. The resulting controller is of predictor-type, which means that it contains finite integrals over past state and input values. The method is a generalization of the well-known model reduction approach for systems with input delay. A recursive procedure replaces delay terms with non-delay ones step by step, from the top of the cascade structure down. Controller gains are computed for the proxy system without delays, while the construction guarantees the same closed loop poles for the delay system and the proxy one. The observer is designed by applying the duality argument and the separation principle is also shown to apply.
Becoming artist, becoming educated, becoming undone: toward a nomadic perspective of college student identity development

In this article, I place my ethnographic project among undergraduate university art students and their professor in dialog with Rosi Braidotti’s figuration of the nomadic subject and her reflections on the importance of creating theoretical alternatives for mapping the embedded and embodied social positions that we inhabit. As educational interlocutors, college students must negotiate expectations and categorizations about age-appropriate relations, career paths, and identity passageways, which are always already framed by Western psychological development discourses. Interested in loosening the grip of these closure-seeking and normalizing discursive practices, I argue for a revision of identity development grounded in a nomadic theory of the subject and engage my data through an alternative analytic of arts-informed assemblage in light of Braidotti’s ideas. In so doing, I uphold my feminist commitment to do theory as both critique and creativity, bringing into view poetic-enough writing and imagery as a...
Designing and evaluating active learning methods for activity recognition

Activity recognition in smart home environments is a crucial step towards fully autonomous assistance and health monitoring. Due to the high variance in house configurations and sensor placements, it is important to collect and label sample sensor data that will be used to train a learning algorithm. Ground-truth activity labels must therefore be provided in some manner for this sample data. The abundance of sensor data makes it infeasible to label all of the data, and active learning can be used to intelligently pick the most informative data to be labeled. In this paper, we describe several active learning methods that we designed and implemented for their applicability to the activity recognition task. We evaluate the methods using the CASAS smart home sensor data and present a crowd-sourcing application for annotation.