cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of parallel fiber stimulation on neurons of rat dorsal cochlear nucleus

We have compared the effects of parallel fiber stimuli on extracellularly recorded neurons showing regular or bursting spontaneous activity patterns in the dorsal cochlear nucleus of rat brainstem slices. Ninety percent of regular neurons failed to respond to stimulus currents (1.4 ± 0.28 mA, mean ± SEM) significantly greater than those (0.4 ± 0.07 mA) that elicited responses from 96% of bursting neurons. Responses of bursting neurons were elicited from widely separated loci along the molecular layer. Kynurenic acid and CNQX or DNQX blocked both spontaneous firing and responses to parallel fiber stimuli of bursting neurons. The same agents also blocked responses of regular neurons but had little or no effect on their spontaneous firing rates. AP-5 caused small decreases in spontaneous rates of both bursting and regular neurons but did not appear to affect responses to stimuli. The data support the hypothesis that the responses of both regular and bursting neurons to parallel fiber stimulation are mediated by glutamate, acting mainly through non-NMDA receptors. Spontaneous activity of bursting, but not regular, neurons also requires non-NMDA glutamatergic transmission, suggesting that the spontaneous firing of bursting neurons, consisting largely of cartwheel cells, may depend upon granule cell activity.
Tendency equations for shear and curvature vorticity in coordinate-independent vector notation

Abstract Equations are derived in coordinate-invariant vector notation for the time rate of change of shear and curvature vorticity. These equations are a generalization of equations in natural coordinates derived 30 years ago by Hollmann, and serve to elucidate the conversion process between shear and curvature vorticity. The new form of the conversion term will make it easier to diagnose its magnitude by computer-based objective analysis methods.
Surgical Management of Severe Colitis in the Intensive Care Unit

Severe colitis, an umbrella encompassing several entities, is one of the most common acute gastrointestinal disorders resulting in critical illness. Clostridium difficile infection is responsible for the majority of nosocomial diarrhea with fulminant C difficile colitis (CDC) carrying a high mortality. Optimal outcomes can be achieved by early identification and treatment of fulminant CDC, with appropriate surgical intervention when indicated. Ischemic colitis, on the other hand, is uncommon with a range of etiological factors including abdominal aortic surgery, inotropic drugs, rheumatoid diseases, or often no obvious triggering factor. Most cases resolve with nonsurgical management; however, prompt recognition of full-thickness necrosis and gangrene is crucial for good patient outcomes. Fulminant colitis is a severe disease secondary to progressive ulcerative colitis with systemic deterioration. Surgical intervention is indicated for hemorrhage, perforation, or peritonitis and failure of medical therapy to control the disease. Although, failure of medical management is the most common indication, it can be difficult to define objectively and requires a collaborative multidisciplinary approach. This article proposes some simple management algorithms for these clinical entities, with a focus on critically ill patients.
Social Class in Relation to Medical School Performance and Choice of Specialty

Summary American medical students come from higher-status backgrounds than would be true if sampling occurred on a random probability basis from the general population. With use of Hollingshead's method of scoring for upper, upper-middle, lower-middle, upper-lower, and lower-lower classifications, estimated incidences for medical students are 32.2%, 22.4%, 26.9%, 14.8%, and 3.7%, as compared with 3%, 11%, 32%, 40%, and 14% for people-in-general. Socioeconomic status is relatively uncorrelated with the premedical academic performance of admitted students and is only slightly related to scholastic and clinical achievement in medical school. Graduates with working class parents tend more often to choose careers in general practice or family medicine. Increased selection of applicants from low status backgrounds would seem to involve few if any dangers and might well contribute to a more abundant future supply of physicians offering primary care.
Characterization of glucose oxidase immobilized on collagen.

The enzyme glucose oxidase (E.C. 1.1.3.4) was immobilized on collagen — a proteinaceous material found in biological systems as a structural material for a wide variety of cells and membranes. The novel technique of electrocodeposition, which utilizes the principles of electrophoresis, was used to deposit the enzyme-collagen complex on stainless steel helical supports. This technique has been developed in our laboratory. The mechanism of complex formation between collagen and enzyme involves multiple salt linkages, hydrogen bonds and van der Waals interactions.
Charge and fission of droplets in electrostatic sprays

Measurements of the charge and size of heptane droplets generated by electrostatic sprays showed that the droplet charge‐to‐volume ratio is a monotonically decreasing function of size. In the useful range of electrospray operation, characterized by droplets smaller than the size of the orifice from which the liquid is issued, it was found that the larger were the droplets the closer they were to the Rayleigh limit. In particular, when droplets had charging levels between 70% and 80% of such limit, they were observed to rupture because the repulsive force due to surface charge evidently overcame surface tension. The rupture phenomenon, here termed Coulomb fission, was also captured in microphotographs that typically showed a droplet with one or two, diametrically opposed, conical protrusions terminating in a fine jet ejecting a stream of much smaller, apparently equisized offsprings. The process appeared swift and, yet, well ordered, quite different from the common view of a violent, convulsive explosion. ...
Abstract PR08: Loss of oncogenic Notch1 signaling contributes to PI3 kinase inhibitor resistance in T lineage leukemia.

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer for which current therapies are toxic and frequently ineffective. Mutations that activate the Notch1 and Ras/PI3K/Akt signaling pathways are common in T-ALL and often coexist. Thus, inhibiting these pathways alone and in combination is a rational therapeutic strategy. Notch1 inhibition with a gamma-secretase inhibitor (GSI) was recently evaluated in patients with disappointing results. PI3K inhibitors are just entering Phase I clinical trials. GDC-0941 is a potent PI3K inhibitor that is currently advancing in clinical development that we evaluated for efficacy and mechanisms of drug resistance both in cell lines and primary murine T-ALLs. Cell lines are uniformly sensitive to GDC-0941, however gradual dose escalation results in resistant lines. In vivo, GDC-0941 is active against primary T-ALLs, but treated mice invariably relapse with drug resistant clones. Unexpectedly, a majority of GDC-0941-resistant cell lines and primary leukemias showed reduced levels of activated Notch1 protein, down-regulate many Notch1 target genes, and display cross-resistance to γ secretase inhibitors (GSIs). In multiple cases, Notch1 mutations that were present at enrollment were absent at relapse. Importantly, resistant clones that emerge both in vitro and in vivo up-regulate PI3K signaling indicating an “on pathway” mechanism of resistance. Consistent with these data, inhibition of Notch1 signaling promotes GDC-0941 resistance and enhances PI3K signaling, whereas expression of activated Notch1 increases the GDC-0941 sensitivity of mouse and human T-ALL cell lines. Thus, oncogenic Notch1 mutations that promote clonal outgrowth during malignant transformation unexpectedly undergo negative selection during treatment with GDC-0941. These studies validate PI3K as an important therapeutic target in T-ALL and raise the unexpected possibility that administering Notch1 and PI3K inhibitors in combination will accelerate drug resistance. Citation Information: Mol Cancer Ther 2013;12(11 Suppl):PR08. Citation Format: Monique Dail. Loss of oncogenic Notch1 signaling contributes to PI3 kinase inhibitor resistance in T lineage leukemia. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr PR08.
Reconciling motor performance indicators from theoretical calculations and laboratory tests

Quite often because of the complexity in the design of large industrial motors, the theoretical motor parameter calculations do not match actual results from laboratory tests. Thus, it becomes important to predict the amount of discrepancy between the two methods to develop confidence in the motor parameter calculations. This paper discusses the development of multiple artificial neural networks (ANNs) designed to predict the ratios of measured parameters to calculated parameters, given the geometry and construction of the motor. These ratios represent correction factors which can be applied to the values calculated from the theoretical program, which, in this case, is a software package known as MPE program.
Injection of a Novel Biomimetic Aggrecan for the Restoration of Intervertebral Disc Tissue Mechanics

Intervertebral disc degeneration and associated lower back pain is one of the leading musculoskeletal disorders confronting our health system with 15%–20% of the population experiencing lower back pain annually [1–4]. It has been shown that early in disc degeneration, the extracellular matrix of the nucleus pulposus is depleted of the proteoglycan aggrecan, resulting in loss of disc hydration, osmotic pressure and mechanical stability which leads to lower back pain [2, 5]. Early-stage restoration of the proteoglycan content within normal levels with natural aggrecan may help to restore disc functionality but it is cost prohibitive. We propose a new strategy to restore the extracellular matrix of the degenerated disc and mitigate lower back pain by molecularly engineering the disc matrix with an injection of a biomimetic aggrecan (BA) novel class of molecules that mimics the 3D bottle brush structure and physical properties of natural aggrecan.Copyright © 2013 by ASME
Monitoring the Conformation of Benzo[a]pyrene Adducts in the Polymerase Active Site Using Fluorescence Resonance Energy Transfer

Benzo[a]pyrene (B[a]P) is a potent environmental carcinogen that is metabolized into diol epoxides that react with exocyclic amines in DNA. These DNA adducts have been shown to block DNA replication by high-fidelity polymerases and induce both base substitution and frame-shift mutations. To improve our understanding of the molecular mechanism of B[a]P-induced mutagenesis, a fluorescence resonance energy transfer (FRET) method was developed in which the (+)- or (-)-trans-anti-B[a]P-N(2)-dG adducts, positioned in the active site of DNA polymerase I (Klenow fragment), serve as donor fluorophores to an acceptor molecule positioned on the DNA primer strand. FRET was measured for a primer that ended one nucleotide before the adduct position and one that ended across from the adduct and used to estimate the distances between the two fluorophores. These estimates are consistent with prior studies that suggest the adducts are positioned in the minor groove. A comparison of the FRET for the (+)- and (-)-trans-B[a]P adducts in the Klenow active site suggested that the (+)-trans adduct is positioned approximately 2 A farther from the acceptor, consistent with the structural differences observed in duplex DNA where it has been shown that the (+)-trans adduct is oriented toward the 5'-end of the template strand while the (-)-trans adduct lies toward the 3'-end. Surprisingly, the adduct position did not change significantly when the primer was one nucleotide longer. The addition of either a correct (dCTP) or incorrect nucleotides showed only minor differences in FRET, suggesting that the adduct did not undergo a large change in the position within the polymerase active site, as expected if the adduct inhibited the polymerase conformational change.
Work In Progress: Reliability Test Facility

At the Rochester Institute of Technology students take courses in Automated Data Acquisition, Electronics Packaging, and Failure Analysis and Reliability. There are also facilities to do reliability testing on printed circuit board assemblies under variable conditions. It is planned to incorporate the reliability test facility into a real-world problem solving experience for the students that combines aspects from the three course areas mentioned. Students will be involved in the design of the testing procedures, working with the data acquisition package that will allow the data to be acquired, and analysis of the data to determine reliability. This paper will present the test facility and processes used for the products being tested, the data acquisition hardware and software used, and plans to implement this into the undergraduate curriculum.
Loudness Adaptation in Acoustic and Electric Hearing

The present study is aimed to evaluate and compare loudness adaptation between normal hearing and cochlear-implant subjects. Loudness adaptation for 367-s pure tones was measured in five normal-hearing subjects at three frequencies (125, 1,000, and 8,000 Hz) and three levels (30, 60, and 90 dB SPL). In addition, loudness adaptation for 367-s pulse trains was measured in five Clarion cochlear-implant subjects at three stimulation rates (100, 991, and 4,296 Hz), three levels (10, 50, and 90% of the electric dynamic range), three stimulation positions (apical, middle and basal), and two stimulation modes (monopolar and bipolar). The method of successive magnitude estimation was used to quantify loudness adaptation. Similar to the previous results, we found that loudness adaptation in normal-hearing subjects increases with decreasing level and increasing frequency. However, we also found a small but significant loudness enhancement at 90 dB SPL in acoustic hearing. Despite large individual variability, we found that loudness adaptation in cochlear-implant subjects increases with decreasing levels, but is not significantly affected by the rate, place and mode of stimulation. A phenomenological model was proposed to predict loudness adaptation as a function of stimulus frequency and level in acoustic hearing. The present results were not fully compatible with either the restricted excitation hypothesis or the neural adaptation hypothesis. Loudness adaptation may have a central component that is dependent on the peripheral excitation pattern.
Disturbance persistence in managed grasslands: shifts in aboveground community structure and the weed seed bank

The length of time and form in which disturbances persist in systems depends on the intensity and frequency of disturbance and on the abilities of resident species to recover from such events. In grazed grasslands, trampling by large mammalian herbivores can periodically facilitate weed establishment by exposing patches of bare ground but whether an intense soil disturbance event results in a temporary increase in weed abundance or a persistent weed problem remains unclear. In May 2002, cattle trampling following heavy rain caused severe damage to nine-month old, rotationally grazed, cool-season pastures (Midwest USA). In September 2002, we compared the aboveground composition of paddocks (i.e., fenced pasture sections) that were heavily disturbed to those that received no damage. Relative to undisturbed paddocks, forage species relative cover was 17% lower in disturbed paddocks, and weed species and bare ground relative cover was 61% and 100% higher, respectively. By September 2004, paddock types did not differ in all aboveground community components. However, the abundance and species richness of weed seeds in the soil seed bank averaged respectively 82% and 30% higher in disturbed paddocks between 2003 and 2004. These findings indicate that a spatially extensive, intense soil disturbance event may soon become undetectable in components of aboveground pasture structure but can persist as an augmented weed seed bank. Because of high weed seed bank longevity, disturbances to formerly disturbed pastures would likely result in higher weed recruitment, with more species represented, than in those which lack previous disturbance. Disturbance history may thus be a useful predictor of weed community composition following subsequent disturbance. Based on empirical data supporting this proposition, we recommend that grassland managers explicitly incorporate disturbance history into dynamic management planning and do not rely exclusively on aboveground characters to evaluate the invasion status or colonization potential of an area by undesirable plants. We emphasize that the ecological legacies of past soil disturbance events cannot only influence the contemporary patterns and processes of grasslands, but importantly, affect their compositional trajectories following subsequent perturbation.
Control of SOx emissions by in‐furnace sorbent injection: Carbonates vs. hydrates

High temperature, isothermal data on SO2 capture by calcium based sorbents were obtained in a dispersed-phase reactor for limestons, dolomites, hydrated calcitic limes, and hydrated dolomitic limes as a function of Ca/S molar ratio, temperature, and SO2 partial pressure. The experimental results indicate that SO2 capture is approximately linearly dependent on Ca/S molar ratio and relatively insensitive to SO2 partial pressure above 2000 ppm. SO2 capture is a strong function of general sorbent class; dolomitic sorbents are better than calcitic materials on an equivalent calcium basis and hydrated materials are more reactive than carbonates. Computer model predictions based on a grain formulation, available fundamental rate data, and measured surface areas accurately predict limestone performance; however, predicted capture for the hydrated sorbents is significantly below that measured experimentally. The measured capture results do, however, generally correlate with the BET surface areas measured when the sorbents were calcined in a muffle furnace at 980 K for 20 minutes with an inert environment.
All-valence-electron and transition density matrix calculations of the electronic spectra of [2.2]paracyclophanequinones

The combined CNDO/S and transition density matrix methods reproduced well the UV-VIS spectra of the intramolecular charge-transfer complexes of double- and triple-layered [2.2]paracyclophanequinones in which benzene and p-benzoquinone represent the donor and acceptor layers: DA, DDA and DAD. Calculations pointed to the already known experimental bathochromic shifts of the longest wavelength absorption band for the DA→DDA→DAD transformations. The electronic transitions corresponding to this band are for DA and DDA the CT transitions of the π→π* type; however, for DAD the band represents the n→π* transition localized on the acceptor ring.
Illuminating qualities of knowledge communities in a portfolio‐making context

This article connects teachers’ experiences of reflective school portfolio development to the idea of teachers’ knowledge communities, the different groups and individuals with whom teachers negotiate meaning for their stories of experience, lived and told, and re‐lived and re‐told, over time. The reflective analysis makes the case that the development of a dynamic knowledge community among teachers is foundational to the successful reflective school portfolio‐making experience. Critically important links between these two phenomena are established by laying texts from school portfolio development meetings alongside the qualities that distinguish teachers’ knowledge communities. In the end result, the research presents a fine‐grained account of teachers actively working in a group situation, contributing to their individual and collective professional development. As such, this article adds to the teacher development and reflective portfolio literatures.
A phase I trial of outpatient weekly irinotecan/carboplatin and concurrent radiation for stage III unresectable non small-cell lung cancer: a Vanderbilt-Ingram Cancer Center Affiliate Network Trial.

Irinotecan (CPT-11), a topoisomerase I inhibitor, has been shown in preclinical studies to be a potent radiosensitizer. Carboplatin, a known radiosensitizer with single-agent activity in non–small-cell lung cancer (NSCLC), is felt to be a rational choice in combination with irinotecan. We have completed the initial portion of a phase I study, in patients with locally unresectable lung cancer, combining irinotecan with thoracic radiation. Thirteen patients have been entered onto this study through three dose levels (30 to 50 mg/m2/week) of irinotecan. There were seven partial responses in 12 evaluable patients, for an overall response rate of 58%. Nausea, vomiting, and esophagitis were the principal toxicities of weekly irinotecan and concurrent thoracic radiation. As the maximum tolerated dose (MTD) of irinotecan with radiation has been established at 40 mg/m2/week, we are currently accruing patients to the second phase of this study with the addition of carboplatin (AUC = 2). Thus far toxicity has primarily been esophagitis.
The Effects of Copper CMP Slurry Chemistry on the Colloidal Behavior of Alumina Abrasives

The effects of common slurry additives on the colloidal behavior of alumina suspensions used for copper chemical mechanical planarization (CMP) were investigated. The alumina suspensions were characterized by zeta potential and agglomerate size distribution measurements with various chemical additives. To simulate the slurry during copper CMP, the effect of the addition of ∼ 100 nm diameter copper particles was studied. The presence of 0.12 mM copper caused a decrease in agglomeration for pH values less than 6.5 and an increase in agglomeration ranging from 200-1000 nm for pH values greater than 7 in aqueous solutions. Addition of glycine caused the formation of a soluble Cu-glycine complex that decreased agglomeration at pH values less than 4. The addition of 0.1 wt % H 2 O 2 did not affect the effective alumina agglomerate size without copper, but with copper in the solution the majority of the alumina agglomerated to ∼2 μm for all pH values. However, increasing H 2 O 2 concentration to 2.0 wt % decreased the agglomerate size by 100-400 nm. The pH of the slurry had the largest effect on the zeta potential and agglomerate size distributions.
On the exponential value of labeled samples

Abstract Consider the problem of classifying a sample X0 into one of two classes, using a training set Q. Let Q be composed of l labeled samples {(X1, θ1), …, (Xl, θl)} and u unlabeled samples {X′1, …, X′u}, where the labels θi are i.i.d. Bernoulli(η) random variables over the set {1, 2}, the observations {Xi}i=1l are distributed according to fθi(·) and the unlabeled observations {X′j}j=1u are independently distributed according to the mixture density fX′(·) = ηf1(·) + (1−η)f2(·). We assume that f1(·),f2(·) and η are all unknown. Let f1(·) and f2(·) belong to a known family F , and assume that the mixtures of elements of F are identifiable. Even when the number of unlabeled samples is infinite and the decision regions can therefore be identified, one still needs labeled samples to label the decision regions with the correct classification. Letting R(l, u) denote the optimal probability of error for l labeled and u unlabeled samples, and assuming that the pairwise mixtures of F are identifiable, we obtain the obvious statements R(0, u) = R(0, ∞) = 1 2 , R(1, 0) ⪕ 2η η , R(∞, u) = R ∗ , and then prove R(1, ∞) = 2R ∗ (1−R ∗ ) , where R ∗ is the Bayes probability of error, and R(l, ∞) = R ∗ + exp { −αl + o (l)} , where the exponent α is given by − log (2√η η ∫ √f 1 (x)f 2 (x) d x) . Thus the first labeled sample reduces the risk from 1 2 to 2R ∗ (1−R ∗ ) and subsequent labeled samples in the training set reduce the probability of error exponentially fast to the Bayes risk.
Time course of the disappearance of pineal noradrenaline following superior cervical ganglionectomy

Pineal glands were collected from superior cervical ganglion-ectomized (SCGX) and sham-treated rats at time intervals following surgical manipulation. Pineal noradrenaline (NA) levels were quantitated by a radioisotopic-enzyme technique, or the pineals were examined by histofluorescence or electron microscopic techniques. A significant decline in pineal NA content was observed by 12 hours with a virtual disappearance of NA by 24 hours following SCGX. The depletion of NA content correlated with the disappearance of synaptic vesicles and the appearance of generalized fine structural degeneration of the sympathetic nerve endings in the pineals. Then results indicate that less than one day is required to remove all of the potentially, functional neurotransmitter from the denervated pineal gland. These observations agree closely with the time course of degeneration of other sympathetic nerve terminals following SCGX.
Effect of post-reflow no-clean solder paste residue on electrical performance

An experiment was conducted to examine the effect of postreflow no-clean solder paste residue of near-end and far-end signal crosstalk due to changes in dielectric constant and leakage resistance in the circuit environment. Additionally, the effect of different frequency levels on postreflow residue was examined. The results suggest that postreflow residues affect the signal-to-noise ratio on circuit boards, depending on the chemistry, residue level, and dielectric properties of these pastes. Higher levels of residues may cause signal degradation on the transmission lines. The noise level on circuit boards increases significantly if a solder paste exhibits excessive residue. Increased crosstalk is believed to be caused by an increase in the dielectric constant (excessive postreflow residues) between two transmission lines. The effect of postreflow residue on circuit performances was more noticeable at frequencies greater than 1 MHz. >
Rapid environmental change over the past decade revealed by isotopic analysis of the California mussel in the northeast Pacific.

The anthropogenic input of fossil fuel carbon into the atmosphere results in increased carbon dioxide (CO2) into the oceans, a process that lowers seawater pH, decreases alkalinity and can inhibit the production of shell material. Corrosive water has recently been documented in the northeast Pacific, along with a rapid decline in seawater pH over the past decade. A lack of instrumentation prior to the 1990s means that we have no indication whether these carbon cycle changes have precedence or are a response to recent anthropogenic CO2 inputs. We analyzed stable carbon and oxygen isotopes (δ13C, δ18O) of decade-old California mussel shells (Mytilus californianus) in the context of an instrumental seawater record of the same length. We further compared modern shells to shells from 1000 to 1340 years BP and from the 1960s to the present and show declines in the δ13C of modern shells that have no historical precedent. Our finding of decline in another shelled mollusk (limpet) and our extensive environmental data show that these δ13C declines are unexplained by changes to the coastal food web, upwelling regime, or local circulation. Our observed decline in shell δ13C parallels other signs of rapid changes to the nearshore carbon cycle in the Pacific, including a decline in pH that is an order of magnitude greater than predicted by an equilibrium response to rising atmospheric CO2, the presence of low pH water throughout the region, and a record of a similarly steep decline in δ13C in algae in the Gulf of Alaska. These unprecedented changes and the lack of a clear causal variable underscores the need for better quantifying carbon dynamics in nearshore environments.
Median Nerve F-Wave Conduction in Healthy Subjects

This study of the normal median nerve was designed 1) to compare techniques of using the shortest and average F-wave latencies, F-wave values between extremities, and F-wave values with the conventional motor response values and 2) to determine the relationships between F-wave latency and arm length. We examined 40 median nerves in 20 subjects with no known pathology. The motor response latency was measured from wrist and elbow stimulation sites by conventional techniques. We then applied multiple stimuli at the same sites to record a series of 10 F-wave latencies and determined shortest and average F-wave latencies. Values of F-wave and M-response conduction are reported. No significant difference was found in F-wave latency or velocity between extremities within subjects, using either the shortest or average latency technique. We propose a formula for calculating the estimated F-wave distal latency based on the conventional motor response distal latency. The F-wave conduction velocities of the forearm were faster and more variable than the motor nerve conduction velocities. A high correlation was found between F-wave distal latency and arm length. Using the method described, the F wave can be a useful measure in evaluating the conduction of proximal segments of peripheral motor nerves.
Towards Real-Time Cue Integration by Using Partial Results

Typical cue integration techniques work by combining estimates produced by computations associated with each visual cue. Most of these computations are iterative, leading to partial results that are available upon each iteration, culminating in complete results when the algorithm finally terminates. Combining partial results upon each iteration would be the preferred strategy for cue integration, as early cue integration strategies are inherently more stable and more efficient. Surprisingly, existing cue integration techniques cannot correctly use partial results, but must wait for all of the cue computations to finish. This is because the intrinsic error in partial results, which arises entirely from the fact that the algorithm has not yet terminated, is not represented. While cue integration methods do exist which attempt to use partial results (such as one based on an iterated extended Kalman Filter), they make critical errors.I address this limitation with the development of a probabilistic model of errors in estimates from partial results, which represents the error that remains in iterative algorithms prior to their completion. This enables existing cue integration frameworks to draw upon partial results correctly. Results are presented on using such a model for tracking faces using feature alignment, contours, and optical flow. They indicate that this framework improves accuracy, efficiency, and robustness over one that uses complete results.The eventual goal of this line of research is the creation of a decisiontheoretic meta-reasoning framework for cue integration--a vital mechanism for any system with real-time deadlines and variable computational demands. This framework will provide a means to decide how to best spend computational resources on each cue, based on how much it reduces the uncertainty of the combined result.
Undergraduates' Experiences with and Attitudes Toward International Teaching Assistants.

Controversy continues to surround the instructional role of teaching assistants at large U.S. research universities who are not native speakers of English and who received their undergraduate training outside the U.S. Interactions between these international teaching assistants (ITAs) and their undergraduate students is sometimes threatened by miscommunication. The study described in this article adapted the Questionnaire About International Teaching Assistants (QUITA) survey instrument (Fox, 1992) to collect background information about undergraduates at one midwestern university, inquiring about their experiences with ITAs and their means for dealing with ITA problems and assessing their attitudes with respect to ITAs. The study examined the relationship between an attitude scale and 11 student background characteristics (e.g., year of enrollment, academic college, age, sex, size of hometown). In addition, focus-group interviews conducted with a subset of respondents explored their experiences and opinions relating to ITAs. The article compares the findings of this study with those of earlier research, including Fox's (1992) study, and recommends intervention strategies with undergraduates who are likely to encounter ITAs.
Activation of Isac promotes atrial fibrillation initiation and perpetuation: is this a stretch?

c s m Atrial fibrillation (AF) is a cardiac arrhythmia that results in a rapid and irregular activation of the atrial myocardium. In humans, activation rates during AF can be as high as 400–600 pulses per minute. About 2–5 million people in he United States are afflicted by AF, and the incidence of he arrhythmia increases with age, affecting 10% of the ctogenarian population. AF is the number one cause of hospitalization for arrhythmias, and its incidence is predicted to double in two decades. Yet the therapeutic management for F is challenging; antiarrhythmic drug therapies are partially ffective, some of which are proarrhythmic. Thus, AF is a ajor challenge in cardiac electrophysiology, and a large perentage of AF patients await novel therapies for the treatment f the arrhythmia. What are the mechanisms of initiation and perpetuation f AF? It is well established that disorders such as congesive heart failure, coronary artery disease, hypertension, and itral valve disease predispose the atrial myocardium to brillation. Furthermore, it has been demonstrated that there is structural, contractile, and electrical remodeling during AF and that this remodeling, in turn, exacerbates the rrhythmia. Nevertheless, a trigger is required for initiating AF. A consensus that has emerged from human and animal studies is that ectopic focal activities originating from areas around the pulmonary veins (PVs) serve as triggers for AF. For example, in one study by Chen et al, the lectrophysiological properties of the atria and the PV reion were examined in 79 patients with frequent episodes of aroxysmal AF. The electrophysiological properties of the V region were found to be different from those of the atria. t was also shown that ectopic beats originating from the PV egion could initiate AF. In another study, Hocini et al investigated the cellular architecture and electrical properties of the canine PV region to determine what may predispose the region to the initiation of arrhythmias. The investigators demonstrated that areas of activation delay correlated with sudden changes in the orientation of muscle
Deterministic modelling of carbon nanotube near-infrared solar cells

Photovoltaics (PVs) using single-walled carbon nanotubes (SWNTs) as near-infrared photo-absorbers have progressed rapidly, offering promise for long-wavelength light harvesting devices. Despite this interest the fundamental design questions remain, such as optimal device thickness, nanotube orientation, density, and the impact of impurities. To address this challenge, we develop a deterministic model of SWNT PVs derived directly from SWNT photophysics using photon, exciton, and charge carrier population balances. The model accounts for arbitrary distributions of nanotube chiralities, lengths, orientations, defect types and concentrations, bundle fraction and size, and density. We show that feasible devices can achieve external quantum efficiencies above 60%. We reveal a sharply optimal device thickness that is a function of nanotube density, orientation, and quenching site concentration. This thickness stems from a tradeoff between exciton generation and diffusion to the electrodes, and is at a minimum at the limit of close-packed nanotube density. We show that this minimum characterizes a given device design and scales with mean nanotube length to exponent 0.4. The normalized difference between optimal thickness and this close-packed limit scales inversely with density to the 0.24 power. Practically, in-plane aligned nanotube configurations yield optimal thicknesses less than 10 nm, increasing to a range of 50 to 200 nm for vertical alignment. Due to weak inter-SWNT exciton transport relative to exceptional intra-SWNT diffusion, vertically-aligned films are unambiguously favored at densities above 3% of the close-packed limit; at lower densities however an optimum emerges at an intermediate angle to compensate for weaker light absorption of vertical nanotubes. Comparison to published experimental devices displays the model's utility for device design.
Early-stage ejecta velocity distribution for vertical hypervelocity impacts into sand

The ejecta dynamics during main-stage excavation flow in a cratering event have previously been well characterized, particularly for vertical impacts. In this experimental study, we present new results addressing the early-time, low-angle, high-speed component of the ejecta velocity distribution as a function of time for hypervelocity vertical impacts into sand. Although this regime represents a very small portion of total ejected mass in laboratory experiments, it comprises a greater percentage of growth for larger craters.
An Analysis of State Special Education Nondiscriminatory Evaluation Policy and Procedures.

Results of a national survey of special education nondiscriminatory evaluation policy that included both an analysis of regulatory language and implementation procedures are reported. State (N=51, ...
Effects of herbivory on internal ethylene production and sex expression in Cucurbita texana.

1. Field-grown Cucurbita texana was used in a study to determine if stress ethylene from damaged leaves promotes changes in sex expression. 2. Internal ethylene concentrations were experimentally enhanced by inserting an ethylene-filled syringe into the hollow chamber of an internode seven nodes from the growing tip of a branch. Branches enhanced with ethylene produced significantly more pistillate buds than control branches and experienced greater bud abortion later in floral development. 3. The timing and magnitude of Diabrotica beetle leaf damage was simulated using a paper-hole puncher (15% removed from all leaves). Simulated herbivory was applied to new growth every 3 days throughout the growing season. 4. Endogenous ethylene concentrations recovered from the internode adjacent to the growing tip were significantly greater in damaged plants than undamaged plants 1 day after damage to new growth during the second and third week of the experiment, and 2 days after damage during the fourth and fifth week. By the sixth week, no significant differences were evident. 5. Damaged plants produced fewer pistillate buds than undamaged plants, indicating that stress ethylene from simulated herbivory does not induce femaleness. A second messenger that suppresses pistillate bud production may be produced during damage.
Microvascular transplantation of a free omental graft to the distal extremity in dogs.

Objective To assess the survival of a free omental graft applied to an experimentally created wound on the distal extremity in dogs. Study Design A free omental graft was evaluated as a primary method of treatment for dogs with distal extremity wounds in an experimental model. Animals or Sample Population Five adult intact female mixed breed dogs weighing 21.8 kg to 25.0 kg. Methods A free omental graft was harvested from the abdomen and transferred to a wound bed overlying the medial aspect of the tibia. A microvascular anastomosis was performed between the graft vessels and vessels at the recipient site. Daily clinical assessment of graft viability was performed. Angiography and 99m Technetium labeled macroaggregated albumin (99mTc MAA) scintigraphic perfusion scans were performed on either day 4, 5, or 7. Postmortem collection of tissues for histopathologic analysis was performed immediately after imaging. Total operative time and graft ischemia time were evaluated for effects on graft survival. Results Two of seven grafts survived to the end of the study, three of seven grafts failed because of ischemia, and two of seven grafts failed because of self-trauma. There was no clinically significant morbidity associated with the abdominal portion of the procedure. Because of the small number of surviving grafts, the effects of operative time and graft ischemia time could not be statistically evaluated. Conclusions Microvascular transplantation of a free omental graft can result in a viable tissue covering of a distal extremity wound, however, the failure rate is unacceptably high. Clinical Relevance A free omental graft may not have sufficient durability to be an acceptable wound covering by itself. Further studies combining omentum with a skin graft or other tissues may result in a clinically useful technique.
A Process for Transferring and Patterning InAs Quantum Dot Optical Gain Media for HAMR Near Field Optical Sources

We report a process by which a 270 nm layer of optical gain medium is transferred to a dielectric substrate via a flip chip process and patterned into disk structures suitable for microcavity lasers. This process is anticipated to have application to near field transducers for heat assisted magnetic recording (HAMR). Specifically, the gain medium consists of 5 layers of InAs quantum dots embedded in GaAs. The transfer process was accomplished by depositing a series of etch stop layers on the GaAs substrate before the QD gain layers, and then using these etch stop layers in a polishing and etching process to remove the substrate of the gain medium. To support the gain medium during this removal, the GaAs wafer was flipped onto an epoxy layer that had been applied to a glass wafer, where the gain medium layer was eventually left in place and separated from the substrate. This gain medium layer on epoxy was then patterned using photolithography and ion milling. Photoluminescence studies show little effect on the optical properties resulting from the transfer and the patterned devices show optical mode structures consistent with an approach to lasing. However, the epoxy substrate is revealed to be too poor a thermal conductor for optical pumping to reach the lasing threshold. Detailed analysis of the temperature rise upon illumination combined with literature values for the lasing threshold pump levels suggests that substrates with thermal conductivities of around 10 W/m-K are required for the process to yield working lasers.
Camera based vehicle detection, tracking, and wheel baseline estimation approach

Detecting and classifying vehicles using a stationary camera is an important task in intelligent transportation systems. A novel vehicle detector is introduced. The vehicle detector uses the most common feature among all vehicles, the ubiquitous wheel. The vehicle detector finds wheels and infers vehicle location from background segmentation and wheel detection. Views from a rigid rectilinear camera are used. The images are convolved using a difference of Gaussian filterbank. The responses from the filterbank are applied to a precomputed set of principle components. The principle component responses are compared against a Gaussian mixture model of wheels and Gaussian mixture model of non-wheels. Wheel candidates are chosen and tracked. Any wheel tracked in the foreground is chosen as wheel. Initial experimental results along with analysis are included.
Characterization of a complex chromosomal rearrangement using chromosome, FISH, and microarray assays in a girl with multiple congenital abnormalities and developmental delay

Complex chromosomal rearrangements (CCRs) are balanced or unbalanced structural rearrangements involving three or more cytogenetic breakpoints on two or more chromosomal pairs. The phenotypic anomalies in such cases are attributed to gene disruption, superimposed cryptic imbalances in the genome, and/or position effects. We report a 14-year-old girl who presented with multiple congenital anomalies and developmental delay. Chromosome and FISH analysis indicated a highly complex chromosomal rearrangement involving three chromosomes (3, 7 and 12), seven breakpoints as a result of one inversion, two insertions, and two translocations forming three derivative chromosomes. Additionally, chromosomal microarray study (CMA) revealed two submicroscopic deletions at 3p12.3 (467 kb) and 12q13.12 (442 kb). We postulate that microdeletion within the ROBO1 gene at 3p12.3 may have played a role in the patient’s developmental delay, since it has potential activity-dependent role in neurons. Additionally, factors other than genomic deletions such as loss of function or position effects may also contribute to the abnormal phenotype in our patient.
Evolutionary economics and environmental imperatives

The long-range biological imperative for survival has its economic counterpart. The present techno-economic system, with its heavy dependence on exhaustible stocks of natural resources, including environmental waste assimilative capacity, is unsustainable. The stocks of high quality raw materials, such as fuels and metal ores, are being drawn down rapidly. But this is the least of the problems because of possible technical ‘fixes’. More ominous, there is an irreversible disappearance of tropical rainforests and other valuable and irreplaceable ecosystems, erosion of topsoil, a buildup of toxic heavy metals in soils and sediments, an accumulation of ‘greenhouse gases’ in the atmosphere, and a catastrophic loss of biological diversity. None of these trends is reversible by any known or plausible technological intervention. Long-run human survival therefore requires that the use of the environment as a ‘sink’ for waste residuals, especially from fossil fuel combustion and dissipative uses of heavy metals, must be slowed down drastically in the near future. The paper examines the relevant economic adjustment mechanisms in terms of both ‘standard’ neo-classical and evolutionary theories. It concludes that a policy based on reliance on market signals (i.e. prices) alone to induce change is likely to be ineffective. Even if the polluter pays principle (PPP) were fully implemented, market mechanisms would not suffice. The problem is that existing large-scale systems evolved during a period when environmental concerns were not serious, and now retain their economic dominance partly due to economies of scale and partly through influence over the political system.
A new method of channel identification

A method of channel identification is proposed that exploits the spectral correlation properties of pulse- and carrier-modulated signals to identify channels in the presence of arbitrary noise and nearly arbitrary interference. Although a pilot or training signal is required, no replica of the transmitted pilot/training signal is needed at the receiver. The price paid for this simplicity and the tolerance to extreme channel corruption from noise or interference is that the method is slow. That is, relatively long averaging times are needed for measurement of the spectral correlation of the received signal. >
Thermal-blooming-induced low-order aberrations.

The low-order (focus and astigmatism) aberrations induced in a thermally bloomed medium with transverse flow were measured. The maximum focus OPD for a 10-cm aperture was measured to be ~0.4 μm at an Irel ≅ 0.5. The maximum astigmatism OPD was measured to be ~1.4 μm at an Irel ≅ 0.4. The low-order aberrations were dominant at Irel ≥ 0.4. For Irel ⪝ 0.4, higher-order terms become more important. Using the measured values of focus and astigmatism as inputs, a loop was closed around a deformable mirror to correct for the measured aberrations. The presence of an iterative condition in which correction for thermal blooming leads to a more severe condition of blooming, and so on, was observed. However the loop converged to a stable condition. The maximum increase in peak intensity on target achieved by closing the loops was 30–40%.