cssi/SciSciGPT-SciSciNet huggingface dataset:
The Endo-siRNA Pathway Is Essential for Robust Development of the Drosophila Embryo

Background: Robustness to natural temperature fluctuations is critical to proper development in embryos and to cellular functions in adult organisms. However, mechanisms and pathways which govern temperature compensation remain largely unknown beyond circadian rhythms. Pathways which ensure robustness against temperature fluctuations may appear to be nonessential under favorable, uniform environmental conditions used in conventional laboratory experiments where there is little variation for which to compensate. The endo-siRNA pathway, which produces small double-stranded RNAs in Drosophila, appears to be nonessential for robust development of the embryo under ambient uniform temperature and to be necessary only for viral defense. Embryos lacking a functional endo-siRNA pathway develop into phenotypically normal adults. However, we hypothesized that small RNAs may regulate the embryo’s response to temperature, as a ribonucleoprotein complex has been previously shown to mediate mammalian cell response to heat shock. Principal Findings: Here, we show that the genes DICER-2 and ARGONAUTE2, which code for integral protein components of the endo-siRNA pathway, are essential for robust development and temperature compensation in the Drosophila embryo when exposed to temperature perturbations. The regulatory functions of DICER-2 and ARGONAUTE2 were uncovered by using microfluidics to expose developing Drosophila embryos to a temperature step, in which each half of the embryo develops at a different temperature through developmental cycle 14. Under this temperature perturbation, dicer-2 or argonaute2 embryos displayed abnormal segmentation. The abnormalities in segmentation are presumably due to the inability of the embryo to compensate for temperature-induced differences in rate of development and to coordinate developmental timing in the anterior and posterior halves. A deregulation of the length of nuclear division cycles 10–14 is also observed in dicer-2 embryos at high temperatures. Conclusions: Results presented herein uncover a novel function of the endo-siRNA pathway in temperature compensation and cell cycle regulation, and we hypothesize that the endo-siRNA pathway may regulate the degradation of maternal cell cycle regulators. Endo-siRNAs may have a more general role buffering against environmental perturbations in other organisms.
Developmental Expression of the Rabbit 55-kDa Zona Pellucida Protein and Messenger RNA in Ovarian Follicles

The events associated with the early stages of oocyte activation and granulosa cell (GC) differentiation during ovarian follicular development have been investigated using immunological and cDNA probes. Because zona pellucida (ZP) proteins provide excellent markers for oocyte activation during early stages of ovarian development, a cDNA encoding a full-length ZP protein with calculated molecular weight of 57,185 (rc55) and a specific antibody to the corresponding native rabbit ZP protein (R55) were developed. Immunohistochemical analysis of ovaries demonstrated that R55 was localized in follicles of animals 2 weeks and older. R55 was localized in the oocytes of primordial follicles and the oocytes and GCs of primary follicles but was undetectable in the GCs of large antral follicles. GCs were isolated from 6-week-old rabbit ovaries and cultured in defined media to demonstrate expression of rabbit ZP proteins by GCs in vitro. Rabbit ZP proteins were localized in the cytoplasm of cultured GCs if these cells were treated with monensin, a compound that blocks glycoprotein secretion. Northern blot analysis with the cDNA probe rc55 revealed that cultured GCs contained a mRNA for R55 and that there is stage-specific expression of the R55 mRNA in developing rabbit ovaries. Immunoblot analysis demonstrated that R55 is detectable at 4 weeks and accumulates in 6-, 8-, and 12-week ovaries which contain developing primary and secondary follicles. Collectively, these data illustrate developmental expression of R55 in oocytes and GCs of rabbit ovarian follicles.
A model matching approach for designing decentralized MIMO controllers

Abstract A frequency-domain methodology for the design of decentralized control systems for multiple-input–multiple-output (MIMO) plants is presented. The method allows the designer to directly specify the disturbance response of the individual loops. The desired responses are incorporated through appropriately chosen reference models. A streamlined reference specification procedure is developed, which allows the designer to visualize the tradeoff between robustness and response speed. This makes it easy to pick a meaningful reference model, and significantly reduces the trial and error iterations necessary to meet the design requirements. The method is applicable to stable, non-minimum phase, irrational, and to a certain class of unstable plant models. The frequency-domain controller synthesis technique produces low order, easily implementable controllers, making the method attractive to the industry. The design examples demonstrate that achieving good disturbance rejection in each individual loop in most cases guarantees satisfactory set-point response, and good decoupling.
Low-intensity electric fields induce two distinct response components in neocortical neuronal populations

Low-intensity alternating electric fields applied to the scalp are capable of modulating cortical activity and brain functions, but the underlying mechanisms remain largely unknown. Here, we report two distinct components of voltage-sensitive dye signals induced by low-intensity, alternating electric fields in rodent cortical slices: a “passive component,” which corresponds to membrane potential changes directly induced by the electric field; and an “active component,” which is a widespread depolarization that is dependent on excitatory synaptic transmission. The passive component is stationary, with amplitude and phase accurately reflecting the cortical cytoarchitecture. In contrast, the active component is initiated from a local “hot spot” of activity and spreads to a large population as a propagating wave with rich local dynamics. The propagation of the active component may play a role in modulating large-scale cortical activity by spreading a low level of excitation from a small initiation point to a vast neuronal population.
Maternal antioxidant blocks programmed cardiovascular and behavioural stress responses in adult mice

Intra-uterine growth restriction is an independent risk factor for adult psychiatric and cardiovascular diseases. In humans, intra-uterine growth restriction is associated with increased placental and fetal oxidative stress, as well as down-regulation of placental 11β-HSD (11βhydroxysteroid dehydrogenase). Decreased placental 11β-HSD activity increases fetal exposure to maternal glucocorticoids, further increasing fetal oxidative stress. To explore the developmental origins of co-morbid hypertension and anxiety disorders, we increased fetal glucocorticoid exposure by administering the 11β-HSD inhibitor CBX (carbenoxolone; 12 mg · kg − 1 of body weight · day − 1 ) during the final week of murine gestation. We hypothesized that maternal antioxidant (tempol throughout pregnancy) would block glucocorticoid-programmed anxiety, vascular dysfunction and hypertension. Anxiety-related behaviour (conditioned fear) and the haemodynamic response to stress were measured in adult mice. Maternal CBX administration significantly increased conditioned fear responses of adult females. Among the offspring of CBXinjected dams, maternal tempol markedly attenuated the behavioural and cardiovascular responses to psychological stress. Compared with offspring of undisturbed dams, male offspring of dams that received daily third trimester saline injections had increased stress-evoked pressure responses that were blocked by maternal tempol. In contrast, tempol did not block CBX-induced aortic dysfunction in female mice (measured by myography and lucigenin-enhanced chemiluminescence). We conclude that maternal stress and exaggerated fetal glucocorticoid exposure enhance sexspecific stress responses, as well as alterations in aortic reactivity. Because concurrent tempol attenuated conditioned fear and stress reactivity even among the offspring of saline-injected dams, we speculate that antenatal stressors programme offspring stress reactivity in a cycle that may be broken by antenatal antioxidant therapy.
Usability and accessibility issues in the localization of assistive technology

People with disabilities are faced with several barriers to computer usage. Various companies provide assistive software that makes computer usage possible for the population with disabilities. While increased awareness of disability issues has resulted in the formulation of guidelines for developing accessible software, such guidelines do not guarantee that the end product will be optimal for a person with a disability [5]. During localization of software it is important to understand the needs and requirements and target culture of users, which is beyond mere translation of the interface language. This project was carried out to provide broad design guidelines which are driven by usability and accessibility issues that were uncovered during the evaluation of an assistive technology software package.
Heat diffusion analysis of the temperature distribution and phase lag build-up in TMDSC specimens

In the present study, a complete model of thermal diffusion in a TMDSC specimen was developed. The numeric simulation of the temperature evolution takes into account the transient terms at early times and assesses the time at which these vanish. The simulation also provides a complete temperature profile in both radial and axial direction within a cylindrical specimen, and underlines the existence of non-negligible temperature gradients within a polymeric sample. The model predicts a heat flow phase based on the thermophysical properties of the specimen, and avoids the use of a complex heat capacity which has no well-founded physical or thermodynamic meaning. Good agreement was found between experimental and predicted heat flow phase angles.
Feasibility Study of Determination of Seismic Performance Factors for Structural Insulated Panels

AbstractThe authors present the results of a feasibility study to apply the major steps of the methodology to quantify seismic performance factors (SPFs) for structural insulated panels (SIPs) as the seismic force–resisting system for residential and light commercial buildings. This methodology uses collapse evaluation to determine acceptable SPFs. Structural response prediction was assessed through the combination of building code seismic provisions, nonlinear dynamic analyses, and risk-based assessment techniques. The SIP system in this study consisted of a rigid foam insulation core sandwiched between two sheets of oriented strand board. Analytical modeling was carried out using seismic analysis software. The results of the preliminary study show that the methodology and the seismic analysis software used in this study can lead to the determination of SPFs for SIP systems, but extensive experimental test results among other data are needed for a comprehensive project to quantify SPFs.
Phoebe: Albedo Map and Photometric Properties

Using clear-filter images from Voyager 2 (effective wavelength 0.48 μm), we have constructed the first-ever digital albedo map of Saturn's moon Phoebe. Most normal reflectances in this new map are between 0.07 and 0.11; the albedo histogram is largely bimodal, suggesting that the satellite is covered predominantly by two different types of surface materials. The highest albedos are confined to isolated, quasi-circular spots 40 to 100 km across, including three spots of varying albedo in a band immediately south of the equator and one especially bright spot at latitude 60°N (normal reflectance as high as 0.13, ≈50% brighter than the average surface). The bright northern spot and the brightest of the southern spots occur at approximately the same longitude, an alignment that gives Phoebe its significant rotational lightcurve. The low resolution of the Voyager images does not permit interpretation of the bright spots' origin. Phoebe's global-average photometric function was determined by combining the satellite's telescopic near-opposition phase curve (S. Kruseet al.1986,Icarus68, 168–175) with absolute disk-resolved reflectances measured from the Voyager images (triaxial-ellipsoid shape assumed with radii 115, 110, and 105 km). Modeling of the telescopic observations supports the presence of a significant opposition surge, although scatter in the data does not allow unambiguous determination of the surge's exact strength. The derived photometric function is consistent with the idea that Phoebe is a C-type object—probably a primitive, captured body related to Chiron, Pholus, and the inhabitants of the Kuiper Belt. The albedo map and photometric information will aid in the planning of high-resolution Cassini images of Phoebe, which will represent our first close look at this class of primitive outer Solar-System object.
Image retrieval based on JPEG compressed data

Image retrieval based on JPEG compressed data is investigated in this research. Two low level features are extracted in the DCT domain to facilitate content-based retrieval. They are tree-structured color representations of the DC coefficients of Y, Cb, and Cr block arrays and the energy distribution of AC coefficients to denote different textured patterns. Multiresolution indexing schemes are employed to achieve fast retrieval with both color and texture features. Finally, the retrieval performance is improved by a new method which combines both color and energy features.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Text-based approaches for non-topical image categorization

The rapid expansion of multimedia digital collections brings to the fore the need for classifying not only text documents but their embedded non-textual parts as well. We propose a model for basing classification of multimedia on broad, non-topical features, and show how information on targeted nearby pieces of text can be used to effectively classify photographs on a first such feature, distinguishing between indoor and outdoor images. We examine several variations to a TF*IDF-based approach for this task, empirically analyze their effects, and evaluate our system on a large collection of images from current news newsgroups. In addition, we investigate alternative classification and evaluation methods, and the effects that secondary features have on indoor/outdoor classification. Using density estimation over the raw TF*IDF values, we obtain a classification accuracy of 82%, a number that outperforms baseline estimates and earlier, image-based approaches, at least in the domain of news articles, and that nears the accuracy of humans who perform the same task with access to comparable information.
Prolonged hormone deprivation and pretest cage adaptation as factors affecting the display of lordosis by female rats.

Abstract Spayed females given no exogenous ovarian hormone for 60 days display relatively low lordosis quotients due to deprivation desensitiaztion, but a second injection 7 days later produces LQ scores within the normal range. Leaving females in the observation cage for 2 hr before introducing the stimulus male, and requiring 50 mounts by the male produces higher LQ scores than those obtained without cage adaptation. Cage adaptation tends to counteract the effects of deprivation desensitization.
Integration of Energy Conversion and Biosynthetic Processes in Bacterial Photosynthesis

MANY species of photosynthetic bacteria can grow in the absence of molecular oxygen (anaerobically) using organic compounds as the sources of cellular carbon1,2. These organisms, however, differ strikingly from non-photosynthetic anaerobes in that they seem to be unable to obtain sufficient energy for growth from dark fermentative catabolism of organic substrates. Whatever the carbon source, the photosynthetic bacteria seem to require light for multiplication under anaerobic conditions2,3. Through the activity of the photochemical system, light energy is converted to chemical energy in the form of adenosine triphosphate (ATP)4,5, the key fuel for biosynthesis in all types of cells. It is possible that at least part of the energy requirement for anaerobic growth of photosynthetic bacteria can be satisfied by exergonic catabolism of particular substances, but so far this has not been shown. Our search for alternative (dark) anaerobic processes capable of generating ATP at significant rates led us to investigate the intimacy of biochemical coupling between the photochemical energy conversion apparatus and biosynthetic metabolism in the photosynthetic bacterium Rhodopseudomonas capsulatus. The initial aim was to determine the length of the time period over which the biosynthetic machinery can function at a normal rate following cessation of illumination. The experiments reported here indicate a very tight coupling between the light-dependent ATP generating system and overall biosynthesis, and also describe an experimental approach which should prove useful in exploring the general problem of how energy conversion and biosynthetic processes are integrated.
Radiation effects in BeO

Abstract Expansion, microstructure, and property observations on irradiated BeO specimens of several grain sizes and densities are reported following neutron irradiation at dosages up to 1.5 × 10 21 nvt (≧ 1 MeV) at temperatures from 100° to 1200°C. The total expansion at 100°C was greater than 6 percent at dosages of ~ 7 × 10 20 nvt and ranged from 5 percent at 600°C to about 1 percent at 900–1000°C at the maximum dosage. The expansion was of two basic types: one in which the specimens remained intact and the strength was essentially unchanged, and a second in which the specimens cracked at the grain boundaries and a marked decrease in the strength occurred. Microcracking was dependent on the volume expansion and occurred in specimens of 10 μ to 20 μ grain size at volume increases ranging from 0.5 percent at 100°C to approximately 1 percent at 1000°C. Factors in the expansion other than microcracking included lattice expansion, clusters of defects, and helium bubbles which formed at the grain boundaries. Above ~ 600°C, a vacancy excess resulted in expansion several times that indicated by the changes in lattice parameters. Helium bubbles were estimated to account for approximately 20 percent of the observed expansion in some cases at 10 21 nvt. Expansion at temperatures above 600–650°C was found to follow first order kinetics in which the rate-controlling process appeared to be vacancy migration. Equations describing the expansion are utilized together with the volume dependence of the microcracking to define the irradiation conditions under which beryllium oxide can be used in practical applications.
Uncoupling primer and releaser responses to pheromone in honey bees

Pheromones produce dramatic behavioral and physiological responses in a wide variety of species. Releaser pheromones elicit rapid responses within seconds or minutes, while primer pheromones produce long-term changes which may take days to manifest. Honeybee queen mandibular pheromone (QMP) elicits multiple distinct behavioral and physiological responses in worker bees, as both a releaser and primer, and thus produces responses on vastly different time scales. In this study, we demonstrate that releaser and primer responses to QMP can be uncoupled. First, treatment with the juvenile hormone analog methoprene leaves a releaser response (attraction to QMP) intact, but modulates QMP's primer effects on sucrose responsiveness. Secondly, two components of QMP (9-ODA and 9-HDA) do not elicit a releaser response (attraction) but are as effective as QMP at modulating a primer response, downregulation of foraging-related brain gene expression. These results suggest that different responses to a single pheromone may be produced via distinct pathways.
Coronary vasospasm as a possible cause of elevated cardiac troponin I in patients with acute coronary syndrome and insignificant coronary artery disease.

Abstract Background Abnormal levels of serum cardiac troponin I (cTnI) are occasionally found in patients presenting with acute coronary syndromes but having insignificant coronary artery disease. Before one concludes that an abnormal cTnI level is a false-positive result, the possibility of coronary vasospasm should be considered. This study investigated whether coronary vasospasm could be a reason for elevated cTnI in this patient population. Methods and Results This investigation enrolled 93 patients who presented to the emergency department with suspected coronary ischemia and had insignificant coronary artery disease. cTnI was elevated in 23 patients (25%) and was normal in 70 patients (75%). Coronary vasospasm, documented by an ergonovine provocation test, was found in 38 patients (41%). Patients with elevated cTnI levels, compared with those with normal cTnI, were older (63 ± 13 y vs 56 ± 14 y, P =.032), had a higher incidence of males (78% vs 52%, P =.049) and positive ergonovine provocation tests (74% vs 30%, P
Abnormalities of Calcium Cycling in the Hypertrophied and Failing Heart

Progressive deterioration of cardiac contractility is a central feature of congestive heart failure (CHF) in humans. In this report we review those studies that have addressed the idea that alterations of intracellular calcium (Ca(2+)) regulation is primarily responsible for the depressed contractility of the failing heart. The review points out that Ca(2+)transients and contraction are similar in non-failing and failing myocytes at very slow frequencies of stimulation (and other low stress environments). Faster pacing rates, high Ca(2+)and beta-adrenergic stimulation reveal large reductions in contractile reserve in failing myocytes. The underlying cellular basis of these defects is then considered. Studies showing changes in the abundance of L-type Ca(2+)channels, Ca(2+)transport proteins [sarcoplasmic reticulum Ca(2+)ATPase (SERCA2), phospholamban (PLB), Na(+)/Ca(2+) exchanger (NCX)] and Ca(2+) release channels (RYR) in excitation-contraction coupling and Ca(2+)release and uptake by the sarcoplasmic reticulum (SR) are reviewed. These observations support our hypotheses that (i) defective Ca(2+)regulation involves multiple molecules and processes, not one molecule, (ii) the initiation and progression of CHF inolves defective Ca(2+)regulation, and (iii) prevention or correction of Ca(2+)regulatory defects in the early stages of cardiac diseases can delay or prevent the onset of CHF.
Measurement of Human Cerebral Blood Flow with [15O]Butanol and Positron Emission Tomography

Although H2(15)O is widely used for CBF measurement by positron tomography, it underestimates CBF, especially at elevated flow rates. Several tracers, including butanol, overcome this problem, but the short half-life of 15O provides advantages that cause water to remain the tracer of choice. We report the first use and evaluation of 15O-labeled butanol for CBF measurement. Flow measurements made in a similar fashion with water and butanol at 10-min intervals were compared in normal volunteers under resting and hypercapnic conditions. Regional analysis showed good agreement between the tracers at low flows, and significant underestimation of flow by water relative to butanol in regions of elevated flow. The observed relationship between the tracers and the curve-fitted permeability-surface area product for water (133 ml.100 g-1.min-1) follow the known relationship between water and true flow. These observations indicate that [15O]-butanol provided accurate measurements of human regional CBF under conditions of elevated perfusion. We conclude that butanol is a convenient and accurate method for routine CBF determination by positron emission tomography.
Zinc-alpha 2-glycoprotein has ribonuclease activity

Zinc-alpha 2-glycoprotein (Zn alpha 2gp) is widely distributed in body fluids and in various epithelia; its gene has been completely sequenced, but its function has long remained elusive. We have found that Zn alpha 2gp has RNase activity, comparable to onconase but two orders of magnitude less than RNase A. The RNase activity of Zn alpha 2gp is characterized by maxima in pH at 7.5, in ionic strength at 50 mM NaCl, and in temperature at 60 degreesC. It is strongly inhibited by ZnCl2, but unaffected by MgCl2. It is partially inactivated (down to 20%) by the placental RNase inhibitor. On synthetic polyribonucleotide substrates, the RNase activity of Zn alpha 2gp is specific for pyrimidine residues [poly(C) and poly(U) equally] and cleaves only single-stranded RNA. For onconase, it has been demonstrated that the RNase activity depends on pyroglutamic acid (pyr 1) as the N-terminus; Zn alpha 2gp also has pyr 1, while RNase A does not. Alignment of the amino acid sequences of Zn alpha 2gp and onconase or RNase A reveals only modest matches. Despite the more substantial overall structural homology of Zn alpha 2gp to class I major histocompatibility complex proteins, Zn alpha 2gp has not been proven to be associated with the immune response and, conversely, we could not detect RNase activity in six class I HLA heavy chains.
Seasonal occurrence of larval and juvenile fishes in a Virginia Atlantic coast estuary with emphasis on drums (Family sciaenidae)

The seasonal occurrence and relative abundance of larval and juvenile fishes, particularly members of the family Sciaenidae, from a Virginia Atlantic coast estuary were determined from ichthyoplankton and otter trawl collections made from March 1979 to March 1980. The larvae of 19 species in 14 families were identified in the ichthyoplankton. Larvae of the engraulid, Anchoa mitchilli (bay anchovy), and the atherinid, Menidia menidia (Atlantic silverside), dominated the samples and made up 13 and 22%, respectively, of the 9,440 larvae collected. Peak occurrence of all larvae was from May to August. The juveniles of 28 species in 19 families were identified from otter trawl collections. Juvenile sciaenids numerically dominated the trawl collecions and made up 68% of the trawl catch. Juvenile density peaked during September through December.
Effects of pressure on deep levels in semiconductors : the MFe center in InP.

This work investigated the effects of hydrostatic pressure on the properties and bistability of the scientifically challenging and technologically important deep MFe center in iron (Fe)-doped, n-type indium phosphide (InP). When occupied by electrons, the center can be reversibly placed in either of two configurations, termed A and B, by the proper choice of electric biasing conditions and temperature. Pressure has a very large influence on the balance between these two configurations, favoring A over B. Above 8 kbar essentially only the A configuration is observed. This result, along with detailed studies of the effects of pressure on the energetics of the two configurations and on the kinetics of the B {yields} A transformation, provide important new insights about the nature of the two configurations and their associated deep levels.
Gastric band erosion and intraluminal migration leading to biliary and small bowel obstruction: case report and discussion

u b d T p Adjustable gastric banding is a safe and effective treatent of morbid obesity that has gained widespread popuarity. One of the complications associated with adjustable astric bands is erosion into the stomach. Larger series have eported an incidence of 1–2% for the adjustable silicone astric band [1,2], the Swedish gastric band (Ethicon Endourgery, Johnson & Johnson, Cincinnati, OH), and the Lapand (Inamed, Irvine, CA) [3,4]. Previously described comlications have included intraluminal duodenal obstruction fter erosion of a Kuzmak adjustable band (BioEnterics, arpinteria, CA) [5], gastric outlet obstruction after laparocopic adjustable gastric band Lap-Band [6] placement, and arly small bowel obstruction after laparoscopic adjustable astric band placement. We present the case of a patient ith gastric erosion and migration into the jejunum with esultant biliary and small bowel obstruction occurring 15 ears after open vertical banded gastroplasty and Kuzmak djustable band application.
Cross sections for production of 149Tb from Au by high-energy protons

Cross sections for the production of the α emitter 149Tb (4.12 h) from gold with protons between 0.6 and 30 GeV have been measured. Some difficulties of earlier determinations were avoided by use of chemically separated, “weightless” sources for the α measurements. A β-active tracer (160Tb) was used for yield determinations. The excitation function obtained is compared with previous results. The individual cross sections reported are believed to be accurate to 4 to 6%.
Spectral Demultiplexing in Holographic and Fluorescent On-chip Microscopy

Lensfree on-chip imaging and sensing platforms provide compact and cost-effective designs for various telemedicine and lab-on-a-chip applications. In this work, we demonstrate computational solutions for some of the challenges associated with (i) the use of broadband, partially-coherent illumination sources for on-chip holographic imaging, and (ii) multicolor detection for lensfree fluorescent on-chip microscopy. Specifically, we introduce spectral demultiplexing approaches that aim to digitally narrow the spectral content of broadband illumination sources (such as wide-band light emitting diodes or even sunlight) to improve spatial resolution in holographic on-chip microscopy. We also demonstrate the application of such spectral demultiplexing approaches for wide-field imaging of multicolor fluorescent objects on a chip. These computational approaches can be used to replace e.g., thin-film interference filters, gratings or other optical components used for spectral multiplexing/demultiplexing, which can form a desirable solution for cost-effective and compact wide-field microscopy and sensing needs on a chip.
Analysis of neural network interactions related to associative learning using structural equation modeling

Brain imaging techniques have the potential of providing information about functional interactions within entire neural networks. Large quantities of data can be obtained from mapping studies, but computational techniques are needed to make sense of the complex network interactions that take place in the brain. Structural equation modeling may provide such a technique by combining the anatomical connectivity with the covariation in the activity between brain regions. Functional strengths of anatomical connections between the structures that form a neural network can be quantified by assigning numerical values to the links. Changes in these values are used as indices of how information is processed and modified within the brain in a given situation. We used brain metabolic data from auditory learning experiments to explain how structural models of the auditory system reveal the patterns of network interactions related to opposite learned associative properties of the same sound. This analysis supports the hypothesis that associative learning is an emergent network property, distributed among interacting brain regions. Understanding such a property requires a network analysis of the patterns of interactions between brain regions, rather than the traditional analysis of regions one at a time.
Serpentine superlattice nanowire-array lasers

We report characterization and modeling of serpentine superlattice nanowire-array lasers. These samples were grown by molecular beam epitaxy on (100) n/sup +/-GaAs vicinal substrates. In-plane ridge-waveguide lasers with ridge stripes either parallel or perpendicular to the nanowire arrays have been characterized at low temperatures. The measured net gain spectra at 1.4 K showed strong optical gain anisotropy such that the TM mode gain became greater than the TE mode gain when the optical cavity was placed along the nanowire direction. This provides strong evidence that the lateral quantum confinement in the serpentine superlattice is stronger than the vertical quantum confinement. Optical gain spectra in the serpentine superlattice are calculated with consideration of coupling between wires and homogeneous line broadening. A good fit to the measured polarization-dependent gain spectra is achieved when the lateral Al segregation and the homogeneous line broadening are chosen to be 8% and 7 meV, respectively. This small but finite Al segregation in the serpentine superlattice provides lateral quantum confinement for holes, which results in significant anisotropy in the relation between net gain and injection current density,. >
The impact ionization coefficient in dielectric materials revisited

Avalanche ionization plays a crucial role in the photoionization of dielectric materials and as such is important for optical damage. Although it has been investigated closely during the last years, there is little experimental evidence of how the impact ionization parameter changes with electron density and/or incident pulse intensity. One reason is that in most dielectric materials there are several competing ionization and relaxation processes. Here we present an UV-pump IR-probe experiment that allowed us to isolate the avalanche ionization from other major ionization processes, especially multiphoton ionization, electron tunneling, and relaxation into traps and their re-excitation. We have measured the intensity dependence of a transmitted IR pulse, propagating through a thin sample of UV-grade sapphire (α-Al2O3), after seeding electrons in the conduction band with a UV pulse. We show that the assumption of an intensity independent impact ionization factor α cannot explain the results. Application of a simple avalanche ionization model within the flux-doubling approximation requires an intensity dependent coefficient a(I) to explain the data. We also determined the two photon absorption coefficient of sapphire at 266 nm (β(2) = (2.7 ± 0.1) • 10-11cm/W) as well as the "free" electron absorption cross section for 800 nm of conduction band electrons in sapphire (δ0 = (12.5 ± 0.2) •10-18 cm2).
Modify and Adapt: Global Higher Education in a Changing Economy

The combinations of global networking and digital delivery have intense repercussions for higher education administrators who confront a magnitude of opportunities and challenges as the result of the digital revolution. Much of the reaction to technological change comes from those with a vested interest in either wholesale change or maintaining the status quo. Taking the resilience metaphor from ecology, the authors propose a framework for analyzing an institution's ability to adapt to digital challenges. To compete in today's economic environment, higher education institutions must become more adaptive, responding more quickly to changing expectations from society, politicians and customers. The non-linear approach to problem-solving evident in higher education and society in general, reflects a need to be more flexible, adaptive to alternative techniques and willing to invest in a new culture designed to acquire knowledge rather than specific solutions. This level of organizational flexibility and responsiveness fuels university performance. In the globally competitive and commercialized start to the 21st Century there has been a considerable increase in the demands for higher education institutions to provide additional global access, and increase opportunities while simultaneously reducing budgets. Globalization and technology have introduced critical alterations to higher education institutions. The context of education has become dynamic, energetic, and economically driven. The emerging technologies have rapidly turned knowledge to power. In this context knowledge is viewed as a commodity that can be managed (bought and sold) while being a vibrant source of social activity and learning.
Corrosion of aluminium in chloride solutions containing some anions—I. In 0.01M NaCl solutions

Abstract A study has been made of the corrosion behaviour of Al in solutions containing 0.01M NaCl alone or mixed with silicate, phosphate, dichromate, permanganate or sulphate ions covering concentration ranges of several orders of magnitude. Chloride ions become adsorbed on cracks in the pre-immersion oxide film. Silicate, phosphate and permanganate play a dual role. At small concentrations they modify the rates of nucleation and growth of the crystalline oxide layer. At higher concentrations they become incorporated in this layer in progressive amounts and hence impair its protective nature. The reduction product of dichromate improves the properties of the oxide film. At small concentrations, sulphate ions simulate chloride ions, but at higher concentrations they are adsorbed on the growing oxide nuclei hindering its growth.
Epidural anesthesia for common surgical procedures

Many common surgical techniques can be conducted with lumbar epidural anesthesia as the sole anesthetic. Many factors influence whether it should be chosen over general anesthesia or another type of regional anesthesia. The less frequently used paramedian approach to the central neuraxis offers several advantages, particularly in patients without palpable landmarks, and/or in patients who are unable to flex because of arthritic or painful comorbid conditions. Specific details of using lumbar epidural anesthesia as the sole anesthetic is illustrated in three common clinical conditions: total abdominal hysterectomy, lumbar laminectomy, and femoral-popliteal bypass.
The asymptotic distribution of the maximum likelihood estimator for a vector time series model with long memory dependence

Abstract A vector time series model with long-memory dependence is introduced. It is assumed that, at each time point, the observations are equi-correlated. The model is based on a fractionally differenced autoregressive process (long-memory) adjoined to a Gaussian sequence with constant autocorrelation. The maximum likelihood estimators for the parameters in the model are derived and their asymptotic distributions are obtained.
Lack of development of pollutant-resistance or genetic differentiation in darter gobies (Gobionellus boleosoma) inhabiting a produced-water discharge site

Abstract Physiological acclimation, genetic adaptation and genetic differentiation were examined in darter gobies (Gobionellus boleosoma) inhabiting a coastal marsh with a long history of PAH contamination. No acclimation was detected; a 2-week pre-exposure at the polluted site resulted in a decreased rather than an increased resistance in a subsequent laboratory exposure to polluted sediment. Similarly, fish collected from sites with elevated sediment PAH levels did not exhibit an increased resistance in bioassays with polluted sediment, confirming the lack of acclimation and indicating a lack of adaptation to the pollutants. No differences were detected in frequencies of allozyme genotypes when comparing gobies from the polluted area to those from a nearby control site, and overall levels of heterozygosity were similar in the two populations. While lack of UV-induced toxicity in the laboratory exposures could have played a role, at least four other factors may explain the apparent lack of adaptive responses and genetic differences. First, bioavailability of the contaminants to the darter goby could have been low, though other evidence contradicts this. Second, the contaminated marsh contains a large number of different chemicals and acclimation, adaptation and genetic differentiation are expected to be less likely when more contaminants are involved. Third, the hydrocarbon distribution at the contaminated marsh is very patchy, such that fish may avoid exposure to the highly-contaminated sediment. Fourth, gene flow may be sufficiently high in this mobile species to prevent local adaptation.
Articulation in Cash Flow Statements: A Resource for Financial Accounting Courses

Abstract Recent accounting research (Bahnson, P., Miller, P., & Budge, B. (1996). Nonarticulation in cash flow statements and implications for education, research and practice. Accounting Horizons, 10, 1–15 has shown that firms implementing the indirect method for reporting cash flows under SFAS 95 rarely produce financial statements that articulate cleanly. The purposes of this paper are (1) to provide financial accounting educators with a list of companies for which articulation does exist, (2) to describe the process by which educators can update the list in the future, or modify it to suit their own preferences, and (3) to present an analysis of firms’ reporting practices on the cash flow statement, which may be of interest to more advanced students studying the complexities of the statement of cash flows. This analysis of reporting practices involves an assessment of the articulation of individual COMPUSTAT line items (e.g. inventory) and subsets of line items (e.g. inventory, receivables, deferred taxes, and depreciation) for the 1998 data year. The findings indicate that relatively few firms report consistent values for single line items and that very few firms report consistent values across subsets of line items. Although the rate of articulation decreases as firm size, and hence reporting complexity, increases, 74 large, publicly-traded firms for which clean articulation does exist were identified. This list of firms should prove useful to introductory accounting educators who use real-world examples for classroom purposes.
Thyroid abnormalities in chronic viral hepatitis and their relationship to interferon alfa therapy

The prevalence of antithyroid peroxidase antibodies (ATPO) and/or of thyroid dysfunction was studied in 422 patients with chronic viral hepatitis C, B, and D. Baseline results were compared with those during and 6 months after interferon alfa (IFN-alpha) therapy. The overall prevalence of ATPO among untreated patients was 14.1%, with no significant differences between chronic hepatitis C, B, or D, as well as between males and females. However, high ATPO titers (> or = 18 IU/mL) clustered significantly among females (8.7% vs. 3.4%; P = .022), especially those with chronic hepatitis C (11.2% vs. 3.6%; P = .036). Before treatment, 3.7% of the patients had thyroid dysfunction, mostly hypothyroidism (3.5%), the latter increasing to 14.3% among patients with ATPO titers > or = 18 IU/mL. IFN-alpha treatment significantly increased overall thyroid dysfunction (9.7%; P = .001) and hypothyroidism (7.8%; P = .01), particularly among patients with high baseline ATPO (38.5%; P = .0002). Six months after stopping IFN-alpha treatment, the prevalence of thyroid dysfunction was 8.0%, still significantly higher than at baseline. By multivariate analysis, the only predictor positively associated with pre- or on-treatment hypothyroidism was the baseline titer of the ATPO antibodies (relative risk [RR], 3.0 and 3.8 per each log titer increase, respectively). In conclusion, patients with chronic viral hepatitis on IFN-alpha treatment exhibit an almost threefold increase of baseline thyroid dysfunction, persisting long after the end of therapy. High ATPO titers, clustering among females, particularly those with hepatitis C, represent the only predictor of pre- and on-treatment hypothyroidism by multivariate analysis. Patients with chronic viral hepatitis, especially females, should be tested for ATPO and thyroid function and monitored during and posttreatment for free thyroxin (FT4) and thyroid-stimulating hormone (TSH) levels.
Atmospheric-pressure microwave-induced helium plasma spectroscopy for simultaneous multielement gas chromatographic detection

Abstract Simultaneous multielement detection for gas chromatography ( GC ) by atmospheric-pressure microwave-induced helium plasma emission spectroscopy ( MIP ) is described and evaluated. A valuable application is in the empirical formula determination of unknown compounds. This technique provides the necessary high sensitivity, selectivity and repeatability for detecting both metals and non-metals. Carbon-, hydrogen-, chlorine-, silicon- and phosphorus-containing compounds are investigated. It is shown that, for many application, GC — MIP is a viable alternative and offers advantages over conventional selective detectors for elements like chlorine (i.e., electron-capture detector) and phosphorus ( i . e ., photoionization and flame-photometric detectors).
Efficacy of Engineering Controls in Reducing Occupational Exposure to Aerosolized Pentamidine

Aerosolized pentamidine administration may pose potential risks to health care workers exposed to fugitive drug and to infectious respiratory pathogens ( eg , tuberculosis) generated by pentamidine-induced cough. Classic infection control methods may be applied to this problem, although the effectiveness of these measures in mitigating environmental pentamidine exposure is unknown. Lack of data fully characterizing pentamidine's mechanism of action or potential mutagenicity, carcinogenicity, or teratogenicity raises concern and suggests worker exposure and environmental contamination be minimized. We report herein on the efficacy of an aerosol containment hood in containing fugitive pentamidine aerosol during administration.
Fuzzy Rule-Building Expert System Classification of Fuel Using Solid-Phase Microextraction Two-Way Gas Chromatography Differential Mobility Spectrometric Data

Gas chromatography/differential mobility spectrometry (GC/DMS) has been investigated for characterization of fuels. Neat fuel samples were sampled using solid-phase microextraction (SPME) and analyzed using a micromachined differential mobility spectrometer with a photoionization source interfaced to a gas chromatograph. The coupling of DMS to GC offers an additional order of information in that two-way data are obtained with respect to compensation voltages and retention time. A fuzzy rule-building expert system (FuRES) was used as a multivariate classifier for the two-way gas chromatograms of fuels, including rocket (RP-1, RG-1), diesel, and jet (JP-4, JP-5, JP-7, JP-TS, JetA-3639, Jet A-3688, Jet A-3690, Jet A-3694, and Jet A-generic) fuels. The GC-DMS with SPME was able to produce characteristic profiles of the fuels and a classification rate of 95 ± 0.3% obtained with a FuRES model. The classification system also had perfect classification for each fuel sample when applied one month later.
Exploring Discrimination in American Health Care System: Perceptions/Experiences of Older Iranian Immigrants

The United States population is older and more diverse than ever before. Older Immigrant and minorities have been found to suffer from health care disparities. The National Institute of Health (2002) has identified discrimination as one of the factors that contributes to health disparities among immigrants and minority populations. The purpose of this qualitative phenomenological study was to explore older Iranian immigrants’ perceptions/experiences of discrimination in their encounter with the American health care system. In depth interviews were conducted with 15 Iranians who had immigrated to the United States after the age of 50. The following major themes emerged from the study: 1) “American doctors don’t discriminate”, 2) class discrimination in American and Iranian health care system and 3) treating the illness and not the whole person. In general the participants reported that they did not perceive/experience discrimination in their encounter with the American health care system. In fact majority of the participants reported highly positive impressions of American health care providers. Some participants claimed that language barriers may have protected them from recognizing possible discriminations, while others reported that this absence of perceived discrimination may be a function of American provider’s perception of a patient as an “illness” and not a whole person.
Computerized Outcomes Assessment Program and How It Changed the Culture of an Institution

Neosho County Community College, is a small college in Kansas. It set out to measure outcomes in every course, program, and in general education. It wound up creating a simple, elegant, inexpensive, faculty-driven system that transformed the college culture from an emphasis on what was being taught to what was being learned.